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Transfusion Medicine | P O S T E R A B S T R A C T S

POSTERS: BLOOD COMPONENTS

PO1 The Biological Effect and Characterization of Erythrocyte Derived Microvesicles R. Freezor & S. Heugh London Metropolitan University, London, UK Microvesicles (MVs) are membrane-coated vesicles released from virtually all cells types, acting as a form of long-distance cell-cell communicator through interaction with surrounding cells, via lipids and functional transmembrane proteins from the parent cell; involving cell surface binding via specific receptors, internalization by endocytosis, micropinocytosis and phagocytosis. The profiling of markers and biological activity of erythrocyte MVs (eMVs) found in plasma/serum can help detect and monitor haematological disease where numbers fluctuate. Fresh erythrocytes collected into EDTA-K3 were isolated by FicollPaqueTM. eMVs were formed in three ways (i) Control - erythrocytes incubated for 45 min, 37 °C with RPMI-40, (ii) as (i) plus 2 mM CaCl2 and (iii) as (ii) plus human serum. eMVs isolated -25,000 9 g for 90 min, labelled with panel of markers, including CD235ab/Annexin-V (+ve control) and CD41/CD14 (ve control) and confirmed and quantified by Guava easyCyteTM flow cytometry and proteomics. Biological action of eMVs with THP-1, Jurkat, PC3-M and MCF-7 were observed by LumaScopeTM 500 time-lapse (bright field/fluorescence microscopy); cell growth rate and viability was recorded for 72 h. Guava easyCyteTM revealed eMVs quantities and sample purity including >93% for (+ve) control and 0.05). There was also no significant difference in 100 day survival between the 2 groups (P = 0.13).

© 2014 The Authors Transfusion Medicine © 2014 British Blood Transfusion Society

C. Gabriel, K. Pl€ oderl, A. Lindenmair, K. H€ oller, D. Theiß, H. Redl & S. Hennerbichler-Lugscheider Red Cross Transfusion Service for Upper Austria, Linz, Austria Cell expansion for clinical applications is mainly performed in the presence of fetal calf serum (FCS). As FCS is known to cause disease transmission and incorporation of xenogenic proteins during cultivation, alternative supplements for cell culture media are desired. In recent years, human serum (huS) and human platelet lysate (hPL) turned out to be as good or even better when used instead of FCS. We developed protocols for the production of huS and hPL and tested them in the expansion of human fibroblasts and adipose tissue derived stem cells (ASC). Quality control included cell counts (platelets, red and white blood cells), sterility testing, pH levels, total protein concentrations and growth factor levels. ASC and fibroblasts were expanded for three passages in media supplemented with FCS, huS or hPL and evaluated microscopically. In the presence of hPL and huS higher population doublings were obtained for both cell types. We therefore conclude that huS and hPL can replace FCS in cell culture of ASC and fibroblasts for clinical applications.

PO15 Xeno-Free Isolation and Expansion of Human Amniotic Mesenchymal Stem Cells C. Gabriel, E. Lugmayr, D. Theiß, K. Witzeneder, A. Lindenmair & S. Hennerbichler-Lugscheider Red Cross Transfusion Service for Upper Austria, Linz, Austria Human amniotic membrane represents a rich source of stem cells to be used in regenerative medicine and tissue engineering. Human amniotic mesenchymal stem cells (hAMSC) are isolated by enzymatic digestion using a collagenase solution containing fetal bovine serum (FBS). Isolation is followed by the expansion in media also supplemented with FBS. Besides the animal origin and the batch to batch variations known for FBS, the potential incorporation of xenogenic factors as well as the risk of xeno-immunization in patients makes it unsuitable for clinical use. Due to high cell doses required for application in patients expansion is necessary. Hence protocols according to GMP requirements need to be established. Human term placentae were obtained from Caesarean section after informed consent. The amniotic membrane was mechanically separated from chorion and incubated for 2 h in a collagenase solution supplemented with or without FBS. The cells were expanded for three passages in media supplemented either with 5% human platelet lysate (hPL) or 10% human serum (huS). The cells were subcultured at a confluence of at least 80% and population doubling times were determined. hAMSC were isolated from seven human term placentae. Isolation in collagenase solution supplemented with FBS showed no differences

Transfusion Medicine, 2014, 24, Suppl. 2, 33–75

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XXXII Annual Scientific Meeting of the British Blood Transfusion Society

in cell counts and morphology compared to the collagenase solution without FBS. In a further attempt the collagenase (for research only) was compared to collagenase suitable for GMP production revealing similar results. Although differences between cells expanded with hPL and huS could be observed, confluence was reached already after three to four days independently of the supplement. Data on population doubling time will be presented. We were able to establish a GMP-conform protocol for the xeno-free isolation and expansion of hAMSC. Preliminary results indicated that there is no need to add FBS to the collagenase solution for the isolation of hAMSC and that the GMP-grade collagenase is equally suitable. Concerning the expansion, FBS can be substituted by either huS or hPL

PO16 An Audit of Adverse Reactions during the Infusion of Thawed Haemopoietic Progenitor Cells C. Wiggins & D. Cains NHS Blood and Transplant Autologous haemopoietic progenitor cells from peripheral blood (HPC-A) are routinely cryopreserved in 10% dimethyl sulphoxide (DMSO) and stored for future transplant. The subsequent infusion of thawed HPC-A is associated with adverse reactions including nausea, vomiting, dyspnea and cardiovascular events. Previous studies have demonstrated that the incidences of these reactions are related to the granulocyte content of the product. An audit of the occurrence of adverse reactions when thawed HPC products were infused between 2011 and 2013 has been performed. The HPC-A products were collected in apheresis units at either University Hospital Southampton, Royal Bournemouth Hospital, Poole Hospital or Salisbury Hospital. They were collected using either the COBE Spectra or the Spectra Optia apheresis system. The products were cryopreserved in 10% DMSO and stored in the vapour phase of liquid nitrogen below 150 °C at NHSBT Southampton. The products were subsequently issued to the hospital transplant units for infusion when required for transplant. 320 infusions were performed over 3 years (2011–2013) with only 9 infusion adverse events reported (2.81%). This is significantly lower than the previously reported incidence of 24.8%. These reactions included nausea, vomiting, shortness of breath, rigor, chest pain and tachycardia. No patients received more than the recommended 1 mL kg1 day1 of DMSO. The volume of product infused ranged from 59mls to 860mls. The total granulocyte count infused ranged from 1.08 9 108 to 276 9 108 and there were no reports of cell clumping on infusion. The duration of the infusion was also recorded. The incidence of infusion adverse events was not observed to be related to either the volume of DMSO or the granulocyte count infused. It was also not related to whether the COBE Spectra or Spectra Optia apheresis system was used for the collection.


PO17 The Role of Immunoadsorption in Transplantation K. Harding NHSBT Filton, UK

Introduction: Immunoadsorption is a process whereby antibodies are removed from a patient’s plasma using a machine that draws the patient’s plasma through columns that adsorb and remove antibody (ies). Rationale: Removing unwanted antibodies enables a patient to receive an organ transplant from a donor with a different ABO blood group or HLA type with a reduced risk of the transplant being rejected. ABO incompatible living donor kidney transplants are currently carried out by the larger renal units in the UK where a combination of immunoadsorption and plasma exchange (by filtration) technologies are used depending on the protocol followed (1). The potential benefit for patients of immunoadsorption over plasma exchange is that, in plasma exchange, all the plasma including anti-coagulation factors and protein bound drugs are discarded and a plasma substitute is required, increasing the risk of infection. In immunoadsorption, only immunoglobulins are removed from the plasma before all the plasma is returned to the patient (2). Future role of immunoadsorption in the UK. The use of immunoadsorption is relatively new in the UK, Europe and Asia and its use is not licensed in the US (3). The demand for ABO and HLA incompatible living kidney donor transplants is likely to continue and from an economic perspective is a much more cost effective option than maintaining patients on dialysis (4). Although currently small, the wider indications and demand for Immunoadsorption, for example in liver, bone marrow and heart transplants, cardiomyopathy and neurological conditions, is likely to increase as column technology improves. As experts in providing therapeutic apheresis, NHS Blood and Transplant Therapeutic Apheresis Services are currently evaluating different technologies for immunoadsorption. This is with a view to providing immunoadsorption for a wide range of clinical specialities and diseases to meet potential unmet demand. References 1. Guidelines for Antibody incompatible Transplantation. British Transplantation Society, Guidance 31st January 2011. 2. Teschner S, Stippel D, Grunenberg R, Beck B, Wahba R, Gathof B, Benzing T, Bust V. ABO-Incompatible kidney transplantation using regenerative selective immunoblobulin adsorption. J Clinical Apheresis 23:000, 2012. 3. Morath C, Becker L, Leo A, Beimler J, Klein K, Seckinger J, Kihm L, Schemmer P, Macher-Goeppinger S, Wahrmann M, Bohmig G, Opelz G, Susal C, Zeier M, Schwenger V. ABO-incompatible kidney transplantation enabled by non-antigen-specific immunoadsorption. Transplantation, 2012. 4. Nephron Clinical Practice 2013;124:79–8.


XXXII Annual Scientific Meeting of the British Blood Transfusion Society 41

POSTER SESSION: CLINICAL AUDIT, SERVICE IMPROVEMENT & QUALITY MANAGEMENT

PO18 Audit of Blood Used for Elective Surgery in Lagos, Nigeria A. Akinsegun,1 S. Ajibola,2 B. Osikomaiya,3 A. Dosunmu,4 A. Dada1 & E. Uche1 1

Department of Haematology and Blood Transfusion, College of Medicine, Lagos State University, Ikeja, Nigeria, 2Department of Medicine, Lagos State University, College of Medicine, Ikeja, 3 Department of Haematology and Blood, Faculty of Clinical Sciences, College of Medicine, University of Lagos, Ikeja, Nigeria, and 4 Department of Haematology and Blood Transfusion, Lagos State University Teaching Hospital, Ikeja, Nigeria

Background: Blood transfusion remains a key component in the resuscitation of surgical patients. Shortages arising from a fall in supply, have contributed to ensure that blood remains very much a vital but limited asset to elective surgeries. This study aimed to audit blood utilisation in elective surgery in our institution. Methods: A retrospective audit of blood usage from 1st January to 31st December 2013 at Lagos State University Teaching Hospital, Ikeja was done involving the patients’ wards, blood groups, type of surgery, the number of units requested, cross-matched, transfused and returned. The cross-match transfusion ratio (CT) and the transfusion index (TI) were calculated. A statistical software package SPSS version 16 was be used for data analysis. The descriptive data was given as percentages. Results: A total of one thousand two hundred and eleven (1211) surgical patients requested for blood for the year, and 2055 units of blood were cross-matched. Only 17.32% of cross-matched blood was used. The cross-match to transfusion (CT) ratio was 2055/356 (5.77) while a transfusion index, the number of units used /number of patients cross-matched was 356/1211 (0.29). Maximum Surgical Blood Order Schedule (MSBOS) for the year using Mead’s criterion was 1.5 *Transfusion index = 1.5*0.29 = 0.43. Discussion: Minimal use of these excessively cross-matched blood leads to wastage of resources, inappropriate use of blood bank staff and depriving patients with greater need of this blood. The values of 5.77, 0.29, and 0.43 for CT ratio, TI, and MSBOS respectively, derived in this study depicts inefficient blood usage. Conclusion: Blood ordering pattern needs a definite change and in surgeries with insignificant blood loss, only blood grouping of the patient should be done to prevent wastages. Keywords : Audit, blood utilisation, elective surgery.

PO19 Understanding the Reasons for Platelet Wastage in a Large Trust H. Lucero, K. Pendry, R. Kettle, H. Belli & J. Uttley Central Manchester University Hospitals NHS Foundation Trust, UK

Aims: To understand the reasons for wastage of platelets that are medically ordered and not used (MONU) and review our practice to develop ways of reducing wastage © 2014 The Authors Transfusion Medicine © 2014 British Blood Transfusion Society

Background: CMFT has a high wastage of platelets of over 6%, with the largest cause group being MONU. Methods: Information was collected from electronic records on cases of wastage due to MONU over a 3 month period (October– December 2013). The issue of platelets over the same time period was also analysed. Standards were developed from BCSH guidelines and the Blood Stocks Management Scheme recommendations. Results: 1220 doses of platelets were ordered; 725 for haematology and 251 for surgery, of which 185 were for cardiothoracic surgery. Seventy doses were wasted due to MONU (5.7%). This equated to the following wastage rates: haematology 10 min, 35 (28%) the time to first issue of Red Blood Cells (RBCs) was >15 min, 55 (44%) RBCs collected in >10 min, 35 (28%) the transfusion started in >15 min. 48% of RBCs were returned to BB, 48% of FFPs were wasted. Out of 300 questionnaires 145 (48%) returned, 110 (76%) staff know the first step after MBLP activation, 26 (18%) know satellite fridge locations, 64 (44%) will inform the laboratory to replace emergency O RhD- blood, 121 (85%) know to stand down the laboratory. 73 (50%) will activate MBLP if needed urgent blood. Conclusion: Inappropriate activations and non compliance with the MBLP. Lack of training, awareness, familiarity, and understanding of the MBLP. Poor communication to blood bank.

PO38 How do you Solve a Problem Like. . .. . .Red Cell Wastage? T. Parker, N. Sheppard & M. Holden Mid Essex Hospital, NHS Trust, UK The future supply of stocks of blood and blood components is a concern nationally and Better Blood Transfusion 3 identifies that reducing blood wastage is a vital part of the work of staff to ensure blood is available when it is needed. Broomfield Hospital, part of Mid Essex Hospitals NHS Trust, is a large District General Hospital and uses approximately 10,000 units


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of red cells per year. However wastage is 3.05% (including AB). As part of the Laboratory’s Blood Action Plan (BAP) a decision was made to try to reduce this figure. Additionally the BAP was used to ensure the appropriate use of blood and blood components, a form was devised for laboratory staff to record evidence of the questioning of requests against the national guidelines. Laboratory records were analysed to determine where wastage was occurring and whether there were any obvious trends, for example,

volume leukapheresis used most intravenous calcium. One centre only gave calcium before or after apheresis procedures. The survey does not provide sufficient data on efficacy and tolerability of oral versus intravenous calcium and so cannot be used to develop full guidance on management. However, the use of oral calcium appears effective and sufficient in some patients. Further work is suggested to try and produce guidance on the management of citrate toxicity.

• at certain times of the week • whether individual staff were ordering more components than necessary • if stock rotation and utilisation was actually happening • were staff issuing units with short expiry dates appropriately.

Recommendations:

Working as a team, staff have ensured that:

• • • •

staff are empowered to question requests for red cells, using a form to record the number of units requested/issued stock is checked and rotated daily units are not routinely issued for standby when ordering new stock a form is used to record the current stock level and the number ordered (including any specific reason why more stock is ordered than usual) wastage, particularly within the laboratory, is discussed at monthly staff meetings.

•

Empowering laboratory staff has been a major part of the process within the Trust to ensure components are issued appropriately and wastage is minimised. By using the form to document verbal requests – whether the products were issued or not - 132 RBC units were potentially stopped from being issued (April 13 – March 2014), affecting 77 patients and a potential financial saving of over £16,000. Staff are gaining confidence in questioning requests, and although this does not always happen, especially during times of staff shortages or when the support of senior staff is not available, a significant reduction in wastage has been achieved and maintained.

PO39 Use of Calcium in Therapeutic Apheresis Procedures – A Survey across Specialist Therapeutic Services NHSBT England M. Suhail Asghar,1 R. Pawson,2 S. Benjamin2 & K. El-Ghariani3 NHSBT – Bristol, 2NHSBT – Oxford, and 3NHSBT – Sheffield, UK

1

Acid Citrate Dextrose solution (ACD) containing sodium citrate and citric acid is used as an anticoagulant agent in automated apheresis devices for the collection/removal of human blood components. ACD produces anticoagulation of the extracorporeal circuit by binding free ionised calcium in the plasma. During an apheresis procedure, patients and donors may experience symptoms of hypocalcaemia and may require administration of intravenous or oral calcium to stabilise their ionised calcium levels and relieve symptoms. There is no current guideline available on the management of hypocalcaemic symptoms during apheresis procedures. This audit was conducted to document current practice in the management of citrate toxicity across NHSBT and to set up guidance to manage these donors/patients. This survey included 96 procedures in 4 STS units and found marked variation in practice between units. The choice between oral and intravenous calcium supplementation seemed to be based largely on previous experience within each STS unit. The centre doing large


• • •

Survey other non-NHSBT apheresis units in UK and internationally to observe their practice initially; Draft a grading system for severity of citrate side-effects and the efficacy of treatment and test its reproducibility between STS nurses; Draft guidance for management of citrate toxicity and pilot in 1 STS unit; and audit compliance with this guidance including efficacy data.

PO40 Improving Consent and Counselling Practices for Blood Transfusion in the Obstetric Population H. Watson, I. McKevitt & J. Austin NHS Grampian, Scotland, UK

Introduction: Obstetric haemorrhage remains one of the most important factors in maternal morbidity and mortality in the UK. Timely and appropriate blood transfusion saves lives but is not without risk. Obstetric emergencies can develop rapidly making maximisation of pre-emptive counselling opportunities essential. Aims: This audit focuses on clinician training to improve and standardise blood transfusion consent and counselling practices for elective caesarean section patients. Methods: Best practice for blood transfusion consent and counselling was researched. The initial audit over a 2-week period included all elective caesarean section patients in our maternity hospital. Knowledge of current practice allowed senior departmental discussions to take place to enable local consensus on best practice. Discussions led to recommendations that all elective caesarean section patients should be: 1. Consented for blood transfusion on the local procedure consent form 2. Counselled appropriately on relevant aspects of blood transfusion Appropriate counselling was decided to be the provision of the NHS National Services for Scotland leaflet: ‘Receiving a transfusion: Information for patients and relatives’. The above recommendations were formally cascaded to the whole obstetric department. Further 2-week audit cycles were conducted to assess departmental progress. In parallel, a patient questionnaire was introduced to gauge the success of the intervention. Results: The initial 2-week audit highlighted that 20% of patients were not being consented for blood transfusion. Similarly, there was no standard way of providing counselling. Following intervention, 100% of patients were being consented for blood transfusion and nearly 70% given leaflets. Crucially, of the patients given leaflets 80% found them informative. These figures continued to be improved upon with subsequent cycles. Conclusion: Discussion and intervention led to significant improvement in results for both consent and counselling practices confirming that simple interventions can lead to marked improvements in patient care.


XXXII Annual Scientific Meeting of the British Blood Transfusion Society 49 PO41 The North West Regional Transfusion Committee’s Audit of Platelet Use and Wastage J. Addison NHS Blood and Transplant, Liverpool, UK

Introduction: Demand for platelets remains higher in the North West region of England than the demand for England and North Wales as a whole. The purpose of this audit was to determine if the demand for platelets in the North West is driven by demand and not inappropriate use, to understand why platelets are sometimes wasted and to demonstrate if recommendations from The 2010 National Comparative Audit of Platelet Use are being fulfilled. Methods: An online questionnaire was devised. Participates were requested to audit a specific number of consecutive transfusions according to BSMS platelet category: BSMS category

Number of transfusion cases

Very high High Moderate Low Very low

40 30 20 15 10

Following analysis of the submitted data a follow up proforma was sent to hospitals requesting further information on those patients who received more than one dose for prophylactic platelet transfusions (not including those required pre-procedure).

estimation of fetomaternal haemorrhage, follow-up of the mother & administration of anti-D. Method: Audit standards -BCSH guidelines: ‘Guidelines for the Estimation of Fetomaternal Haemorrhage’ September 2009; & ‘BCSH guideline for the use of anti-D immunoglobulin for the prevention of haemolytic disease of the fetus and newborn’ January 2014. Data was collected over a two-month period, with eight blood banks in Northern Ireland performing the Kleihauer test being the primary source of information. Data was collected on a number of areas:

• • • • • • • •

Number of Kleihauer tests performed Sample labelling Request form details – Kleihauer & flow cytometry Size of FMH Samples referred for flow cytometry Anti-D: quantity & timing Follow-up samples Comparsion of Kleihauer & flow cytometry result

Results and Conclusion: The findings confirmed that although the majority of FMHs are less than 4mls, large FMHs do occur, mostly without a definitive cause & these require even more meticulous management. There was a significant proportion of the latter that were not managed to the required standards. Mothers were not followed up at the required times, flow cytometry was requested without an initial Kleihauer test and sufficient anti-D was not always given. Request forms for both Kleihauer and flow cytometry were lacking in details. All trusts received feedback and a standardised request form for estimation of FMH by flow cytometry was created to aid collection of necessary data. A re-audit is planned.

Results:

• • • • • •

96% of prophylactic transfusions had a pre transfusion platelet count. 14% of prophylactic transfusions received more than 1 dose, following further submission of follow up data this was reduced to 4%. 77% had a platelet count that was consistent with the indication for the request. 68% of transfusions had an indication for the request present on the request form. 82% of pre-procedure transfusions had a post transfusion platelet count prior to their invasive procedure. 7% of platelets were wasted during the audit period.

Conclusions: Although the results show 77% appropriate use of platelets and a reduced level of double dosing, this is only demonstrated in a small number of hospitals. More work is required to drive and promote appropriate use, to further reduce double dosing and to reduce platelet wastage.

PO42 Audit of the Estimation of Fetomaternal Haemorrhage in Northern Ireland A. Sadiq & K. Maguire NIBTS, Northern Ireland, UK

Introduction: Fetomaternal haemorrhage (FMH) may occur during pregnancy or at delivery and lead to immunisation to the D antigen if the mother is D negative and the baby D positive. This can result in haemolytic disease of the fetus and newborn (HDFN) in subsequent pregnancies. It is important to assess the volume of FMH to determine the dose of anti-D immunoglobulin required to prevent sensitisation. NIBTS undertook a regional audit of the © 2014 The Authors Transfusion Medicine © 2014 British Blood Transfusion Society

PO43 Improving Blood Transfusion Ordering in Obstetric Patients– Analysis of Current guideline use and Unused Units G. Artis,1 N. McGuire,1 S. Barr2 & E. Harrison3 1

University of Glasgow, Glasgow, UK, 2Southern General Hospital, NHS Greater Glasgow and Clyde, Scotland, UK, and 3Transfusion Practitioner NHS Greater Glasgow and Clyde, Scotland, UK

Background: Blood transfusion in obstetrics is common, particularly following post-partum haemorrhage. There is a high level of return of blood products, which could be considered a waste of NHS resources. The use of a Maximum Blood Ordering Schedule (MSBOS) is employed to try to minimise this wastage by having standard indications for blood usage. Methods: Crossmatch requests in the Princess Royal Maternity unit and Southern General Hospital Maternity unit were obtained between March–May 2012 and May–July 2012 and 2013, respectively. Indications for crossmatch were recorded and compared to the MSBOS. Number of returned blood was also recorded. Findings: There were 470 crossmatch requests (116 PRM 2012; 166 SGH 2012; 188 SGH 2013). 1115 units were issued in total as a result (264 PRM 2012; 405 SGH 2012; 446 SGH 2013). Of these, approximately 75% were returned (77.6% PRM 2012; 74.8% SGH 2012; 75.1% SGH 2013). Blood requirements were greater at SGH due to the presence of an on-site fetal medicine unit performing routine intra-uterine transfusion. The majority of requests were otherwise in the context of post-partum haemorrhage; these were also the women most likely to receive blood. Over 80% of requests were appropriately made in context of the MSBOS.


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Conclusions: There have been a large number of returns to the blood bank at the Unit. This did not appear to be due to inappropriate ordering but rather an overestimation of blood requirements. Current guidelines do not appear to have been effective in preventing wastage. The guideline has now been updated, including converting previously obligatory crossmatch to group and save only and shortening reservation times after caesarean section to allow more efficient re-use of blood. However, blood requirement in obstetrics is often unpredictable and therefore a degree of wastage will always be anticipated in the context of emergency situations

PO44 Challenges Facing Implementation of Strengthening Laboratory Management Toward Accreditation (SLMTA) Program in Blood Transfusion Service in Kenya E. Wakaria,1 C. Rombo,2 P. Mwamba,1 M. Oduor2 & K. Tilock1 Global Communities, South Africa, and 2Kenya National Blood Transfusion Service, South Africa 1

Introduction: The Strengthening Laboratory Management Toward Accreditation (SLMTA) approach is accepted regionally to effectively implement the requirements for clinical laboratories international accreditation standards. Apart from quality laboratory testing, quality practices in collection, transporting, storing and issuing of blood are also essential. The Global Communities Blood Safety program funded by the U.S. Centers for Disease Control and Prevention (CDC) through U.S. President’s Emergency Plan for AIDS Relief (PEPFAR) supports the Kenya National Blood Transfusion Service (KNBTS) to implement SLMTA in its national office and the regional centers. Methods: In January 2013, a baseline audit was conducted at 6 regional blood transfusion centres and the national office using the SLIPTA checklist. SLMTA I and II workshops were held and intervening mentorship visits were conducted. Gaps identified in each phase of implementation of the program were noted and discussed with relevant stakeholders. Solutions were suggested to address the challenges and to improve the program. Results: There was shortage of trained assessors with technical expert in blood transfusion medicine to conduct the baseline audit. The SLIPTA checklist did not cover some aspects of blood transfusion services including blood donor management, transportation and storage. Since workshop participants were drawn from various cadres, learning activities needed customization to suit the scope of services and relevance to blood transfusion. Successful implementation of improvement projects required involvement of various departments in blood transfusion hence more time was required to implement them. Experienced mentors and trainers in blood transfusion medicine were not easily available. Conclusion: Challenges were encountered in all phases of the SLMTA implementation including: baseline audits, workshops and mentorships. Mentors with experience in blood transfusion have been identified for the next cycle of mentorship. An additional SLMTA trainer of trainers from KNBTS has been allocated to aid in the implementation of SLMTA. Learning activities relevant to blood transfusion are used during the training. There is need for SLMTA toolkit to be more easily customizable to cover blood transfusion services

PO45 Documenting Consent for Blood Transfusion K. Macgill & E. Harrison Royal Hospital for Sick Children, Glasgow, Scotland, UK

Introduction: Currently there is no legal requirement to obtain written consent before giving a blood transfusion, however the Advisory Committee on the Safety of Blood, Tissues and Organs (SaBTO) recommended in October 2011 that ‘valid consent for blood transfusion should be obtained and documented in the patient’s clinical record by the healthcare professional1.’ This project aimed to audit the rates of documentation of consent for blood transfusions prior to and following the implementation of a new national Parent Information Leaflet (PIL). Methods: A retrospective audit of patients’ case records for evidence of documentation of verbal consent being obtained for blood transfusion. Initial audit included all patients transfused in all wards from September to November 2012. PILs were distributed around all wards in the hospital in July 2013. The audit was then repeated in October 2013 and rates of consent compared. Results: In the initial audit cycle, a total of 70 patient’s case records were reviewed. Of these, 23 patients (33%) had evidence of consent documented. Anaesthetists were most likely to document consent for blood transfusion as part of their overall consent discussion pre-operatively. Following the introduction of PILs, 59 patient’s case records were audited. Of these, 13 patients (22%) had evidence of consent documented. This was most evident in general medical and surgical wards where 80% of cases were completed by junior doctors, who used the consent adhesive label from the PIL. Conclusions: In general, consent for blood transfusion is poorly documented in the RHSC. Although overall rates of documentation of consent were lower in the re-audit, the case records that did have consent recorded were using the adhesive labels from the Parent Information Leaflets. Therefore in the ward areas where these are used, PILs have increased the rates of consent documentation. Recommendations: 1. Clinicians should be advised on the need to document consent for blood transfusions, as set out in SaBTO guidelines. This could be done at hospital induction or during departmental/ hospital wide education sessions. 2. PILs should be used routinely as part of the consent process for blood transfusions in RHSC. These need to be more widely circulated and all clinicians informed of their use. All ward managers (or link person in each ward) should ensure these are readily available and visible, as a prompt for obtaining informed consent. 3. There should be a modified consent form for patients who are regularly transfused, which can be updated as necessary as clinical risks change.

PO46 Haemovigilance Reporting in the UK 2013 – Collaboration to Reduce Confusion P. Bolton-Maggs,1 D. Poles,2 A. Watt2 & M. Dawe3 SHOT, Manchester, 2SHOT, and 3MHRA, UK

1

The MHRA is the competent authority for the UK for the reporting of serious adverse events and reactions in line with the definitions in



XXXII Annual Scientific Meeting of the British Blood Transfusion Society 51 the European Blood Directives adopted into UK Law under BSQRs 2005. SHOT, established in 1996, collects additional data, particularly related to clinical incidents, many of which are not required by BSQR. Currently, all reports are entered via the MHRA SABRE system where the reporter can choose the subsequent allocation to one or other or both. Review was undertaken of all reports made in 2013 (January to December). Reconciliation for serious adverse reactions (SAR) includes ABO-incompatible transfusions, transfusion-related acute lung injury, transfusion-transmitted infections, haemolysis, anaphylaxis/hypersensitivity and febrile non-haemolytic reactions. Cases were matched using the MHRA reference number and analysed by category of report. Overall 3692 incidents were reported, 124 (0.4%) to MHRA only, 2415 (65.4%) to SHOT only and 1153 (31.2%) to both. Surprisingly, only 607 (16.4%) were common to both organisations after exclusions and withdrawals. These comprised 239 reaction reports and 368 adverse event reports. However, altogether 450 reaction reports were made to SHOT of which 192 (42.67%) were not reported to MHRA (some may not match the EU definitions of severity). These were found in most categories including 149 acute transfusion reactions, 13 haemolytic reactions and 27 cases of transfusion-associated circulatory overload. A further 23 of the 450 SHOT reactions were reported to the MHRA but were either excluded (15) or incomplete (8). The adverse event categories were more difficult to compare as they are more variably defined by each organisation. Further analysis will identify why there are differences in the two systems and work will continue towards a joint system which may produce a less confusing picture of Serious Adverse Incident Reporting in the United Kingdom.

PO47 Transfusion of K+ Units to Women of Child-Bearing Age A Snapshot (2014) H. Davies & C. Davis Welsh Blood Service, Pontyclun, Wales, UK The WBS issues approximately 100,000 units annually. Units which have been typed as K- will be labelled accordingly. Approximately 9% of the population are K+ and approximately 9% of the donor population are new donors and will not be accredited for K. Rh and K phenotyping is completed routinely at WBS, resulting in >70% of donations available to hospital laboratories with phenotype information printed on the label. Current BCSH Guidelines (2006)1 state: ‘The incidence of anti-K could be reduced by selecting K negative units to females of child bearing age, therefore selecting K negative units for females 90% had a pre-operative G&S. Transfusion rates were 14.5% for THR & 12.5% for TKR. Increased age in THR & pre-operative Hb 160 were transfused. Key Messages: BNHH (1) and national guidelines (2) were not followed for both documentation and clinical practice. There needs to be documented indications for transfusion. A patient with a preoperative Hb of 0.05) between IO blood and VB sodium and potassium measurements was observed; haemolysis and lipaemia associated with IO specimens may be of significance in explaining these differences. Difficulties were encountered regarding IO specimen volume, communication and specimen preparation procedures. Further investigations to confirm the theories hypothesised to explain a lack of correlation between sodium and potassium may be required. In addition the reliability of a wider range of biochemical and haematology markers may be a useful future project. In conclusion, IO blood may be used as a reliable alternative to VB in emergency care setting for pathology analysis of Hb, blood type serology, and serum creatinine and urea. Analysis platforms employed by the RD&E Blood Sciences laboratory did not encounter any complications processing specimens of IO origin.

PO57 Use of Recent Haematocrit and Haemoglobin S Levels Improves Apheresis Red Cell Exchange D. Potok,1 A. Chauhan,2 S. Clarke3 & C. Hood1 NHSBT, Leeds, UK, 2NHSBT, Bristol, UK, and 3NHSBT, Oxford, UK

1

Background: NHSBT Therapeutic Apheresis Service treats patients with sickle cell disease with regular red cell exchange 6 to 8 weekly using 6 to 8 units per exchange. Closer collaboration with trust Haemoglobinopathy Specialist teams has lead to closer monitoring of haematocrit (Hct) and Haemoglobin S (HbS) levels pre- and post-exchange. Regular joint reviews highlighted incremental rises in patient Hct post exchange, and as many patients are exchanged due to increased risk of stroke, maintaining an optimal haematocrit is a key element in minimising this risk. Method: Case review found that regular exchanges were maintaining HbS well within the desired range, but sometimes resulting in increased Hct. Once this trend was identified, parameters entered in the apheresis cell separator were adjusted and pre-exchange HbS levels used to program the machine and determine replacement red cell volume rather than the 100% HbS machine default setting previously used. Post HbS levels were monitored and over time Hct was reduced to the desired level as result of the lower red cell replacement volumes required.


XXXII Annual Scientific Meeting of the British Blood Transfusion Society 55 The net results of these changes has been the ability to reduce the frequency of red cell exchange and the number of red cell units used per exchange in some patients. Conclusion: Reducing red cell exchange frequency and/or number of red cell units used per exchange can result in: 1. less exposure to allogeneic blood with potential for reduction in allo immunisation and cross matching issues 2. less frequent attendance for red cell exchange and associated central line insertion or peripheral vein access 3. reduction in red cell usage and potential usage of rarer phenotype units by using fewer units per exchange.

PO58 Recognition of Transfusion Associated Circulatory Overload in Patients Aged Over 70 Years A. Bartholomew1 & D. Watson2 1 Northumbria Healthcare NHS Foundation Trust, and 2NHS Blood and Transplant, Newcastle, UK

In 2012 there were 82 cases of Transfusion Associated Circulatory Overload (TACO) reported to the Serious Hazards of Transfusion scheme in the United Kingdom representing an increase in the number of reports by 15.5% since 2011 (Cohen, 2012). Accounting for 5% of all the reports made in 2012, it was further implicated in 6 patient deaths and in 29 cases of major morbidity resulting from blood transfusion. TACO occurs when a patient’s circulatory system is unable to handle an increase in circulatory volume leading to cardiogenic pulmonary oedema with 21% of cases being life-threatening to the patient. The audit used retrospective data routinely collected as part of the patient’s transfusion episode over a 3 month period in 2012, involving patients over the age of 70 years in a Trust in the North East of England. Data was analysed to determine: 1. the incidence of TACO within the trust and whether this upholds an indication of under-reporting 2. any observable links to TACO in patients over the age of 70 years 3. whether an algorithm or check list is required to assist with prescribing blood components for this vulnerable group of patients. Data was collected on 234 patients, accounting for 501 blood components. The initial findings suggest that not all units transfused are recorded on the fluid balance charts, and if they are, the fluid balance chart is sometimes incomplete; the patients weight is not always recorded in the notes and there have been several possible cases of TACO identified. The findings will be presented locally, regionally and nationally to raise awareness of TACO and to suggest the requirement of a national comparative audit with a view to obtaining a much wider national picture of any observable links in this vulnerable group.


PO59 Authorising Blood: Can a Non-Medical Signature Make a Difference? A. Benton,1 Y. Rees1 & K. Shreeve2 1 Abertawe Bro Morgannwg University Health Board, and 2Welsh Blood Service, Wales, UK

National developments propose that non-medical health care professionals may adopt an extended role in making the decision to transfuse and in providing the written instruction for transfusion (Green & Pirie, 2009). The purpose of developing such an extended role is primarily to streamline the patient pathway and ensure that transfusion decisions are taken by those directly involved in that patient’s care and assessment. To equip non-medical clinicians with the clinical skills, knowledge, competence and confidence to undertake this task safely and appropriately requires a significant investment by the individual and their employer. Demonstrating actual benefit for all parties is not readily measurable and encompasses more than just time saved for patients or medical staff. In Wales, although quantitative data to demonstrate effectiveness remains elusive, individual experiences and ‘patient stories’ provide compelling qualitative justification for expanding the numbers of non-medical practitioners equipped to deliver this extended role as authorisers. We would like to share some of these stories and our experiences to date, through case studies presented from the perspective of a newly qualified non-medical authoriser, getting to grips with the implications of signing on the dotted line. Reference 1. Green, J., & Pirie, E. (2009). A Framework to Support Nurses and Midwives Making the Clinical Decision and Providing the Written Instruction for Blood Component Transfusion. Retrieved from http://www.transfusionguidelines.org.uk/docs/pdfs/BTFramework-final010909.pdf.

PO60 Choose the Right Path – Better Blood Transfusion Education Pathways D. Creighton,1 S. Cottrell,2 M. McGarvey,2 L. Pirie,2 L. Stout2 & A. Lander2 1

SNBTS, Edinburgh, UK, and 2SNBTS, Scotland, UK

Introduction: In 2012 Better Blood Transfusion conducted a survey of roles undertaken by specific staff groups involved in the blood transfusion process. Following the survey it was agreed that a pilot would be undertaken to evaluate a Learning Pathway option. The pathway option would tailor learning from either Module 1 Safe Transfusion Practice or Module 2 Blood Components and Indications for Use to the role undertaken by the specific staff groups. Aim: The aim was to investigate the feasibility of developing learning pathways for specific staff groups. Method: A short life working group (SLWG) was set up to review the survey findings and the pilot results, and agree minimum learning requirements for the following staff groups: Laboratory Staff, Perfusionists, Porters, Phlebotomists and Healthcare Support Workers (HCSW). Findings and Discussion: The SLWG reviewed the pilot results and feedback. Learning Pathways were developed tailoring the learning content to the role undertaken by each specific staff group involved in the blood transfusion process. For Porters (Unit 1 and Unit 5) and Phlebotomists (Unit 1 and Unit 4). Additionally


56


Phlebotomists would be required to watch the Safe Sampling for Blood Transfusion (video). Both staff groups would have access to a Basic Blood Groups Aide Memoir that was developed to complement the pathway. Agreement was reached for transfusion Laboratory Staff to complete the Transfusion Laboratory Safe Practice module every 2 years. The mandatory training requirement for Perfusionists was to complete the full Module 1 Safe Transfusion Practice. Learning Pathways for Specialty Trainees, Middle Grade Trainees and Consultants was identified with input from a number of clinicians from selected NHS Boards. However the feedback from the pilot was that the pathway was still over onerous in the amount of learning required. These results have been fed back to Scottish Clinical Transfusion Advisory Committee (SCTAC) for discussion on how to take this forward. Although feedback from the HCSW pilot was that the pathway was more relevant to their role and met their learning needs. The SLWG could not reach agreement for a minimum Learning Pathway for this group due to the wide variation of their involvement in the transfusion process across the NHS Boards and individual hospitals, further limited by functionality of the learning management system. Conclusion: Individual training requirements have been shared with the Transfusion Practitioners and the Hospital Transfusion Teams. The Porters and Phlebotomist pathways were launched on the 1st of April 2014. Further scoping for HCSW is required going forward to determine the evolving role of the role in clinical practice. Limitations of functionality of the learnpro system were a factor in providing a HCSW pathway and this will require to be taken to the next User Group Meeting. SCTAC are progressing the training for Medical staff with NHS Education Scotland.

PO61 To What Extent Does Undertransfusion Occur in Modern Clinical Practice? S. Hibbs,1 D. Miles,2 J. Staves2 & M. Murphy3 1

University of Oxford, 2Oxford University Hospitals NHS Trust, and NHS Blood and Transplant, UK

3

Objective: To explore whether undertransfusion is a problem in modern clinical practice. Background: The medical community is increasingly aware of risks associated with blood transfusion, and numerous steps have been taken to reduce the amount of blood products administered to patients inappropriately. However, there is also a need to monitor whether blood products are being underutilised in patients who would benefit from transfusion. Methods: All patients with a haemoglobin level (Hb) below 6 g dL1 or platelet count (Plt) below 10 9 109 L1 during a 1-week period were identified across a large tertiary care trust. Patients who had received a relevant transfusion within 24 h of the low reading were excluded from further analysis. For all other patients, full records were sought to ascertain the reason for withholding transfusion. Results: During the study period there were 15 eligible Hb readings and 21 eligible Plt readings, corresponding to 26 patients. Of these, nine patients had not received a relevant transfusion within 24 h of the low reading. Three of the nine had normalised readings within 24 h without transfusion and so the initial reading was judged to be erroneous. Of the six remaining patients, withholding transfusion was medically indicated for two patients and one other patient was receiving end of life care. There was partial evidence that withholding transfusion was justified for the other three patients but full confirmation was hampered by inaccessibility of patient notes. Discussion: A significant proportion of patients with very low Hb and Plt readings do not receive transfusions. It is likely that there is


good reason for withholding transfusion in the majority of these. However, as efforts to reduce inappropriate overtransfusion continue, systems to monitor for undertransfusion must also be developed.

PO62 Blood, Sweat and Tears- Establishment of a Strategic Partnership S. Laidler, D. Palmer & P. Irving Mid Staffordshire General Hospital, UK Following the initial hub and spoke model proposed as an alliance between 2 sites, further developments with the involvement of the TSA have led to the planned amalgamation of the Trusts UHNS and Mid Staffs to the effect that blood sciences will be combined with overall management based in UHNS. Although this has been proposed theoretically as a sustainable model, the actual practicalities of how this can be achieved without compromising service users has been left to individual workstreams that consist of staff from each trust. Regular meetings have been held and it soon became apparent that a number of problems require solutions if the alliance can proceed within the expected timescale. Whilst the alignment process affects many services within each trust, the purpose of this poster is to specifically highlight the pairing of two transfusion departments – including site specific allocation of work based on a projected work flow, such as the implementation of a hot lab. General problems to be considered are staff recruitment and retention, staffing adaptation with regards to shift changes, training, blood traceability and technical compatibility such as IT systems Some solutions are in place, such as the implementation of common blood transfusion analytical technology and a twinned interface allowing interaction of analysers between sites allowing senior authorisation from remote access. Installation of Haemanetics blood tracking systems across both sites allows common procedures and training protocols for management of blood product issue. The timescale of proposed collaboration completion creates a pressure to progress, which may give rise to less thorough consideration of the impact of implementing new systems Since this process is happening in real time, the purpose of this poster is to illustrate the developments and issues up until now, with recognition that this is an ongoing process.

PO63 Why are We Transfusing Young Women Today? A Retrospective Audit of Transfusion Practice in Women Less Than 40 Years of Age in a UK Hospital K. East,1 C. Ellis2 & M. Offer2 1

Heatherwood and Wexham Park Hospitals NHS Trust, and Heatherwood and Wexham Park Hospitals Foundation NHS Trust, UK

2

Introduction: Appropriate blood transfusion is an essential support to many medical and surgical treatments and may be lifesaving. Of particular concern is inappropriate transfusion in patient groups with a long life expectancy and in particular women of childbearing age. Aim and Objectives: 1. To capture the indications for red cell transfusion in female patients 10 g dL1. Encourage 1-unit transfusions. Consultant approval for all transfusions for patients with reversible anaemia, and the lab to question inappropriate requests. Investigating better use of IV iron. Patients to have transfusion information discussed at booking/ 28 weeks during pregnancy.

PO64 Is One Dose of Anti-D Enough; Investigation of Potentially Significant Factors H. Jones & G. Powell Sheffield Teaching Hospitals, Royal Hallamshire Hospital, UK Following the NICE (2008) recommendation STHNHSFT offer one dose of 1500 iu to RhD negative women at 28 weeks, it was noted that the number of women with a positive antibody screen at delivery due to prophylactic anti-D was reduced. Research indicated that maternal weight and fetal ABO group may be significant factors in the outcome of the antibody screen. Should this influence the dose of anti-D that should be administered? This study looked at 620 RhD negative women who delivered at STH within an 8 month period. The presence or absence of injected anti-D was compared with the maternal weight at booking and the ABO compatibility between mother and baby. Antibody screens were carried out using NBS two cell screen and Biorad gel card technology. Out of 380 women, the average weight for women with a positive antibody screen was 66 kg compared with 73 kg for women with a negative antibody screen. Using an independent one tailed t-test, P = 8.094 9 108 Maternal weight appears very significant in the presence or absence of a positive antibody screen. Fetal cells which are ABO incompatible with the maternal blood group are cleared from the maternal circulation faster than those of a compatible group. This study aimed to determine if this would impact on the presence or absence of injected anti-D at delivery. 240 samples from group O RhD negative women were included. 152 delivered group O babies, 65 delivered group A babies and 23 delivered group B babies. Using chi square analysis P = 0.054 (significance at P = 0.05) this indicated that fetal ABO group did not impact the antibody screen result. These results suggest that ABO compatibility between mother and baby does not affect the detection of anti-D at delivery yet the maternal weight does. The significance of a negative antibody screen at delivery is uncertain.


PO65 Two Thirds of ABO-Incompatible Transfusions Have No Adverse Clinical Consequences 17 Years of SHOT Data P. Bolton-Maggs,1 J. Ball2 & D. Poles2 1

NHSBT, Manchester, UK, and 2SHOT, UK

ABO-incompatible transfusions are one of the most feared results of errors in the transfusion process since they may be associated with death or major morbidity associated with intravascular haemolysis leading to renal failure. However this does not always occur. We reviewed the cumulative data from SHOT reports of ABO incompatible transfusions to examine the outcomes and also see if there was any relationship to the volumes transfused. Since the start of reporting until December 2013 (17 years), 282 ABO incompatible red cell transfusions were reported. Death resulted in 19/282 (6.7%), and major morbidity in 76/282 (27.0%). It is notable however, that the majority of transfusions, 187/282 (66.3%), were not associated with symptoms. Review of the quantity of blood transfused in the 32 cases reported in the 4 years 2010 to 2013 inclusive demonstrated that there was no relationship between the amount and outcome. Death resulted in one patient after less than 50 mL, while 10/17 (58.8%) other patients received between 100 mL and 3 incompatible units without adverse effects. The number of ABO-incompatible transfusions reported to SHOT each year has reduced from a peak of 36 in 1997/8 to about 10 particularly after the introduction of the Blood Safety and Quality regulations in 2005, suggesting improved laboratory safety has had an impact. Currently ABO-incompatible transfusions are only reportable as ‘never events’ to NHS England when associated with harm or death. This results in an underestimate of the risk. These transfusions are always caused by error and should never occur. There is no way of predicting which will cause death, and every one should prompt a serious incident review. Only 2/4 such events were reported to NHS England in 2012 indicating that even reporting of serious events is incomplete. SHOT recommends that all ABO-incompatible transfusions should be recorded as ‘never events’.

PO66 Assessment of Inappropriate Use of Emergency Group O RhD Negative Red Cells in a Large Teaching Hospital K. Glover, J. Staves & M. Murphy Oxford University Hospitals, UK

Background: Group O RhD negative red cells are used in emergencies as the ‘universal donor’. At OUH, the use of O RhD negative red cells is 13%, higher than the 10.5% NHSBT recommendation. This study analysed the emergency use of O RhD negative red cells for its appropriateness. Methods: Patients receiving emergency O RhD negative red cells at OUH in July and November 2013 were assessed for the appropriateness of its use based on National Blood Transfusion Committee (NBTC) guidelines. Results: 34 patients were transfused with emergency O RhD negative red cells. Medical records were obtained on 21(62%) patients. The use of emergency O RhD negative red cells was appropriate in 12 (57%) patients, as they had a ‘mandatory’ or ‘acceptable’ NBTC guideline indication. In 9 (43%) patients, transfusions were deemed inappropriate because a valid blood sample should have been or was present (7; 77%) so cross-matched blood could have been issued, or the patients were haemodyamically stable (2; 22%). 8 (66%) of those appropriately transfused were given 2 units or less in line with guidelines. Further use of O RhD negative red cells was


58


not thought to be appropriate in the other patients. 4 (44%) of those inappropriately transfused also received over 2 units. 10 (83%) patients appropriately transfused with emergency O RhD negative red cells received further blood products in the next 24 h in contrast to 3 (33%) patients inappropriately transfused. Conclusion: This study found that 43% of emergency O RhD negative red cell transfusions at OUH were inappropriate either because a valid blood sample should have been or was present so that crossmatched blood could have been issued or the patients were haemodyamically stable. These findings may partially explain the high use of O RhD negative red cells, and indicate the need for further training of clinical staff.

PO67 BCSH Requirement for an Additional Sample in the Case of FMH Quantification Post Blood Grouping: Is it Necessary? S. McNamara,1 J. Quigley,2 L. Mac Keogh,3 D. Merrin,4 R. Segurado3 & J. Fitzgerald3 1 National Maternity Hospital, 2National Maternity Hospital, Dublin, Ireland, 3National Maternity Hospital, Dublin 2, Ireland, and 4 Coombe Women & Infants University Hospital Cork Street, Dublin 8, Ireland

Background: The British Committee for Standards in Haematology (BCSH) guidelines for the estimation of fetomaternal haemorrhage (FMH) recommends that ‘separate samples are used for maternal blood group and FMH estimation, as there is a theoretical risk that an FMH test performed on the same sample could underestimate the true FMH’. We aim to investigate the distribution of maternal/fetal cells in samples following centrifugation, and to assess the risk of preferentially losing one or the other when sampling the maternal specimen for blood grouping, prior to FMH testing. Methods: Cord blood was added to adult blood samples at varying concentrations to mimic FMH. Kleihauer Betke test (KBT) was carried out pre and post cord blood spiking on all adult samples. The samples were then ABO & RhD grouped using either automated or manual techniques before a final KBT. A selected number of samples were then analysed utilising Flow Cytometry for confirmation analysis. Summary of Results: Both automated and manual grouping indicated a decrease in the KBT post grouping with a more significant decrease in samples post manual grouping. The differences post group however were not of statistical significance. This indicated that although a loss of fetal cells was apparent post manual grouping it did not have a significant effect on the subsequent FMH quantification. Thus the dose of Anti D Immunoglobulin administered based on FMH quantification post grouping will sufficiently prevent maternal alloimmunisation. Conclusion: The research carried out found no evidence to support the outlined theoretical risks published in the guidelines. It has been clearly shown that one blood sample can be used to effectively carry out all tests required in the determination of the both the blood group and FMH estimation without compromising either test. References 1. Austin E, Bates S, De Silva M,et al. Guidelines for the estimation of fetomaternal haemorrhage. British Committee for Standards in Haematology (BCSH), Transfusion Task Force. 2009. 2. Kleihauer E., Braun H. & Betke K. (1957). Demonstration of fetal haemoglobin in erythrocytes by elution. Klinische. Wochenschrift, 35, 637-638.


PO68 A Case of Haemolysis Following Administration of Intravenous Immunoglobulin M. Bridgham,1 M. Drake2 & K. Maguire1 1

Northern Ireland Blood Transfusion Service, Belfast, UK, and Department of Haematology, Belfast City Hospital, Northern Ireland, UK

2

A previously fit and well 64 year old woman was admitted to hospital with a 2 days history of paraesthesiae of both lower limbs. On examination she had upper and lower limb weakness with reduced sensation and generalised areflexia. Initial laboratory tests were normal. She was diagnosed with Guillain-Barre Syndrome. Treatment with intravenous immunoglobulin therapy was arranged. A dose of 2 g kg1 divided over 5 days was selected and she received 120 g Privigen (CSL Behring). On the final day of treatment she became jaundiced. Liver function tests showed mild hyperbilirubinaemia (35 lmol L1) and transaminitis. Haemoglobin was normal (132 g L1). Over the next 7 days there was a progressive fall in her haemoglobin to a nadir of 87 g L1. This was associated with rising bilirubin, reticulocytosis and undetectable serum haptoglobins. Blood film showed spherocytes. Direct antiglobulin test showed IgG positive, C3d negative. The patient was blood group AB Rh D positive. Antibody screening identified anti – A. A final diagnosis of haemolytic anaemia due to passive transfer of Anti – A from intravenous immunoglobulin therapy was established. She was transfused one unit of packed red cells and commenced on folic acid supplementation. Haemoglobin improved to 113 g L1 by day thirteen following immunoglobulin therapy. She made a full recovery and was discharged home 6 weeks later. The episode was reported to the MHRA ‘Yellow Card’ scheme and the product manufacturer. Intravenous immunoglobulin is used as an immunomodulatory agent in the treatment of a wide range of disorders. Common side effects include headache and allergy. Clinically significant haemolysis has been reported but is rare; the mechanism being the passive transfer of blood group antibodies. Suggested risk factors include higher cumulative dose, higher antibody titre and recipient blood group. Recent SHOT reports have also highlighted this phenomenon and clinicians should be aware of this rare but serious side effect.

PO69 Anti-D – a Continuing and Evolving Problem T. Davies,1 P. Bolton-Maggs,2 D. Poles2 & J. Keidan2 1

NHSBT, Manchester, UK, and 2SHOT

Adverse events associated with anti-D immunoglobulin are included in the annual SHOT report as they provide a useful insight into process errors which may be applied to transfusion as a whole. Reporting categories for anti-D include late/failure of administration, placing women at risk of becoming sensitised, or inappropriate administration exposing women unnecessarily to a product made from pooled human plasma. In the 2013 SHOT Report 354 adverse incidents relating to anti-D were reviewed. In 286/354 (81%) cases prophylaxis was delayed, omitted or underdosed, and in 68/354 (19%) cases anti-D was inappropriately administered or handled poorly. In 299/354 (85%) cases, the primary error was made by midwives, nurses and doctors. Key systems failures in the process include lack of communication between healthcare teams, a lack of knowledge and training in healthcare professionals making treatment decisions, pressure of work and availability of experienced senior staff, and general poor practice including manual transcription of critical © 2014 The Authors Transfusion Medicine © 2014 British Blood Transfusion Society

XXXII Annual Scientific Meeting of the British Blood Transfusion Society 59 blood grouping information between paper records and a culture of completing the healthcare record before the intervention has actually been performed. The clinical impact of such errors is unknown as there is no long term follow-up of cases. SHOT is now conducting a survey of all cases of newly diagnosed anti-D in pregnant women to gain a better understanding of the causes of immunisation. Consistency of practice in hospitals is not helped by conflicting guidance for prophylaxis from NICE and BCSH, especially in the early stages of pregnancy, nor by poorly evidenced recommendations to change route of administration for particular products in larger women. SHOT continues to promote partnership working between clinical area and laboratory to ensure the best possible treatment for pregnant women, and it is reassuring to discover from the 2013 National Comparative Audit that we get it right more than 90% of the time.

PO70 How Well Does NHSBT Provide Blood for Genotyped Patients? F. Green1 & K. Ridgwell2 1

NHSBT, Filton, and 2BITS/IBGRL, NHSBT, UK

The provision of optimally matched blood depends on the donor base, the amount and extent of donation typing, stock management, and the nature of the patient population. NHSBT routinely performs 1.7–1.9 million RhcCDeEK groups on whole blood donors annually, plus 250 K extended phenotypes, 10 K ‘complex’ extended phenotypes, and HbS typing on a number of donations. As part of an evaluation of molecular platforms available for donor blood group genotyping, the current ability to provide blood for genotyped patients from extended phenotyped stocks was investigated. A snapshot of antigen matched unit availablity could help inform recommendations for the introduction of molecular typing of donors and highlight where phenotyping could be improved. NHSBT’s PULSE GUI application was used to locate antigen matched units available on a particular day, in both local centres (Filton and Colindale), and nationally, for one hundred patients previously genotyped by the IBGRL molecular diagnostics laboratory (50 patients referred by Filton RCI – mostly autoimmune cases, and 50 referred by Colindale RCI – mostly BME patients). This snapshot investigation found that antigen matched blood was available nationally for almost all patients referred for genotyping by Filton and Colindale, with little variation in availability between the two patient groups. Genotyping information on the GATA mutation in Fy(a-b-) patients was particularly helpful in locating suitable units for these patients. The most common reason for reduced availability of units for some patients was lack of s antigen typing. Until recently, the only available anti-s typing regents were polyclonal IgG making routine testing difficult. A monoclonal IgM reagent is now undergoing validation. Increased extended phenotyping, including more s typing, would help to ensure better matching for more patients, but blood group genotyping may be a more cost effective option as more antigens could be tested than is possible using serological methods.

PO71 An Unexplained Anti-D, or is it Anti-G? T. Lofting Southampton University Hospitals NHS Foundation Trust, UK Anti-G can be formed by G-, RhD- patients (genotype rr). It is usually discovered in RhDpatients who have never been knowingly


exposed to RhD+ products, however an antibody that looks like a combination of both anti-C and anti-D is identified. It can be induced from exposure of an rr patient to either an r’ or an R0haplotype either by pregnancy or transfusion. The clinical significance of anti-G is only really apparent in HDN. This report describes the case of a 64 years old female who was found to produce antibodies after transfusion of 40 blood products over a period of a month. Routine studies initially identified anti-D and anti-C antibodies. This patient however had never been given RhD positive blood products so the question of ‘where did this antiD come from’ arose. Investigations revealed that the donors for the products transfused were rr apart from one pool of platelets in which one of the donors was found to be C+. The antibody was therefore identified as anti-G stimulated by the very small amount of C+ red cells from that single donation in the pooled platelets. History from the patient revealed multiple pregnancies in all of which she have RAADP. All of her children were RhD positive and there was also a report of one miscarriage. It is therefore believed that the primary stimulus for the anti-G was during a previous obstetric episode and that the transfusion of the pooled platelets constituted a secondary response This patient will only ever receive rr blood, however, she also requires HLA matched platelets that are frequently RhD Positive. We will continue to monitor her antibody status but as she is no longer of childbearing age, this antibody should be of minimal clinical significance in this case.

PO72 Serum Ferritin and Total Top-Up Transfusions in Sickle Cell Anaemia: Revisited N. Akinola,1 R. Bolarinwa1 & L. Bisiriyu2 1

Obafemi Awolowo University and Teaching Hospitals Complex, and Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria

2

Serum ferritin (SF) was measured in the steady state and vaso-occlusive crisis (VOC) of adult Nigerian sickle cell anaemia (SCA) patients to determine its association with the total number of red cell top-up transfusions (TUT) received and iron overload. Ethical approval and informed consent were obtained. Fifty two SCA patients (30 in steady state and 22 on the first day of VOC) and 17 age and sex-matched apparently healthy Hb AA controls were recruited. A questionnaire was used to obtain demographic data and the total TUT received. Full blood count and serum ferritin assay (ELISA kit) were obtained from 10 mL of venous blood. The mean SF level in crisis (919.8 433.3 lg L1) was significantly higher than in the steady state (586.5 457.8 lg L1; P = 0.0103) which was significantly higher than in controls (96.0 65.5 lg L1; P < 0.0001). Seventeen (56.7%) patients in steady state had SF levels above 400 lg L1 and 23.3% had levels above 1000 lg L1, while 50% of patients in VOC had SF levels above 1000 lg L1. Five (16.7%) patients in the steady state and 68.2% of crisis patients had never been transfused. Four of the seven steady state patients with SF above 1000 lg L1 had received 0–7 TUT. The mean total TUT received by steady state patients (4.2 4.6) was significantly higher than those received by crisis patients (0.4 0.7; P < 0.001). Serum ferritin levels correlated only with total TUT (r = 0.517; P < 0.01) in this group of patients. Conclusion: This preliminary study shows that more than half of the steady state patients had elevated SF which was significantly higher during VOC. All patients with steady state SF levels above 1000 lg L1 should be investigated for iron overload irrespective of the total TUT received. Possible implications of these observations are discussed.


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PO73

the patient. Accurate information is therefore crucial to help to make appropriate judgements and recommendation.

CSI: FMH E. Lee,1 C. Cantwell,2 D. Gabril,3 M. Hazell4 & F. Regan5 1

NHSBT Colindale, 2St Mary’s Hospital, 3Newham University Hospital, 4International Blood Group Reference Laboratory, and 5 NHBST, UK The answer to a mystery needs clues, such as evidence from clinical information and additional testing. Routine laboratory investigations may not always be able to provide the answer, without addition information. During Fetomaternal Maternal Haemorrhage (FMH) estimation, the diagnostic tests may provide conflicting results. We reports cases of FMH in which results obtained using markers other than anti-HbF and anti-D were useful in reaching a conclusion. Case 1: A group O, D- woman with b Thal delivered in March 2014, the Kleihauer showed more than 4 mL bleed, and the sample was referred to Red Cell Immunohaematology (RCI) Colindale for flow cytometry. No D+ cells were detected by FITC BRAD-3 anti-D. However, routine Rh&K grouping in a gel card showed mixed field (MF) reactions with anti-C and anti-K suggestive of a large FMH. The use of anti-K by flow cytometry revealed that 49.36% of the red cells were K+, making the MF reaction unlikely to be due to FMH. This case was finally resolved when it was confirmed that this K+ patient had been transfused with 4 units of group O D- K- red cells before the FMH sample was taken.

Reagent

Anti-HbF

Anti-C

Anti-K (MIMA-23)

Anti-D (BRAD-3)

Percentage

4.9%

9.92%

49.36%

0

Case 2: A baby born in January 2014 with Hb 66 g L1, was typed as O D+ R1R1 S+s+ K-, and maternal blood was typed as A D+ R1R1 K- S+ s- Fy(a-). Kleihauer results showed more than 125 mL bleed. However, there can be problems with the acid elution technique as HbF increases during pregnancy and a raised HbF is often seen in b thalasseamia, sickle cell anaemia and hereditary persistence of fetal haemoglobin (HPFH). Flow cytometry with anti-D can be used if baby is D+ and mother is D. An alternative approach using monoclonal antibodies other than anti-D was applied and confirmed the FMH that had been obtained using anti-HbF.

PO74 Non-Medical Authorisation of Blood Transfusion- Who Benefits? S. Beuschel Welsh Blood Service, UK Blood components are no longer legally defined as medicinal products and the need for them to be prescribed exclusively by a registered medical practitioner is not necessary. This means that suitably trained, non-medical healthcare professionals such as nurses, midwives and pharmacists may authorise blood transfusion. In Wales, a national programme of training, assessment and qualification of non-medical authorisers of blood transfusion (NABT) has been established with the aim of streamlining the patient pathway and increasing the safety of transfusion. Access to the course requires that a clinical need for NABT has been identified and the appropriate resources agreed and confirmed (Health Board support, provision of a medical mentor, study leave, agreement of the nominated nurse, midwife, pharmacist). The training provided prepares the candidate to undertake this specialist role which ensures that the decision to transfuse is taken appropriately and the patient is prepared for transfusion by qualified staff who are fully aware of the risks, benefits and alternatives and who can provide informed holistic support. The course is accredited by Swansea University and consists of 10 study days, clinical case studies, clinical assessments, MCQ exam and a 3000 word narrative account. Following successful clinical assessments and certification there is a formal sign-off with the employing Health Board prior to service delivery. This poster will describe the results of a small qualitative study assessing the student’s evaluation of the course and the impact of their role as NABT practitioners on the service. The results indicated that the course was well received and that, where NABT practitioners were introduced, blood transfusion rates had reduced, informed consent improved and patient satisfaction increased.

PO75 Reagent

Anti-HbF

Anti-s (MIMA-174)

Percentage mL bleed

5.35% 117 mL

5.33% 116 mL

Anti-D (BRAD-3) Not applicable

Acute Haemolytic Transfusion Reaction: DAT Negative Autoimmune Haemolytic Anaemia without Demonstrable Allo-Antibodies S. Grey & C. Barnes Bolton NHS Foundation Trust, UK

Case: A baby girl born in April 2014 with Hb 77 g L1 was typed as A D and maternal blood was typed as A D+. Kleihauer results showed a very high bleed. Routine flow cytometry with FITC BRAD-3 anti-D was used to detected a minor population was the Dcells. The result indicated that of more than 8.12% (178.3 mL) of fetal red cells were detected. Discussion: Evidence from testing with background clinical information is the tool to help to resolve such problems. Routine FMH using anti-D can only quantify the presence of D+ cells in D population. However, in some circumstances, additional tools such as monoclonal antibodies other than anti-D can be useful (may not be CE marked) for investigation of minor populations, in order to provide useful information for the clinical team in the management of


Introduction: The patient had completed chemotherapy for CLL 2 years previously and had no residual disease. He developed an autoimmune neurological condition that was treated with IVIG and high dose steroids. He also developed autoimmune haemolytic anaemia (DAT negative) and pure red cell aplasia (treated with steroids). His PNH screen was negative. He had persistent haemoglobinuria, hyperbilirubinaemia, raised LDH, reticulocytosis and splenomegaly (awaiting splenectomy). He developed symptomatic anaemia which required several transfusions that were administered uneventfully. He suffered a reaction to his last transfusion. An hour after the start of the second unit he developed fever, rigors, loin pain, vomiting and markedly increased haemoglobinuria. His bilirubin sharply increased and haemoglobin incremented slightly. He was treated symptomatically and fully recovered. © 2014 The Authors Transfusion Medicine © 2014 British Blood Transfusion Society

XXXII Annual Scientific Meeting of the British Blood Transfusion Society 61 Investigation: An unidentified pan-reactive (IAT) antibody had been intermittently detected over the course of the previous year. The pre and post transfusion samples both contained a pan-reactive papain auto-antibody with unidentified reactions with all cells by IAT. No allo-antibodies were identified in adsorbed plasma (or serum), no antibodies were detected by IAT in the eluate, and the DAT remained negative. The post-transfusion re-crossmatch was found to be incompatible, but compatible with adsorbed plasma. The pre-transfusion crossmatch had initially been recorded as compatible – error cannot be excluded. He was genotyped for numerous high frequency antigens, and eluate tested with numerous rare phenotypes. Conclusion: Symptoms and signs of haemolysis within 24 h of transfusion and a positive crossmatch are suggestive of an AHTR. Allo-antibodies were not identified, but allo-antibodies to high frequency antigens cannot be completely excluded. It is possible that transfusion accelerated haemolysis caused by the auto-antibody, possibly because the target antigen is less well developed on endogenous immature red cells, but more strongly expressed on older donor red cells. Pre-transfusion IVIG may decelerate haemolysis if transfusion is required before splenectomy.

PO77 ABO Mismatched Renal Transplantation in Northern Ireland K. Maguire,1 K. Morris,1 R. Melanaphy1 & A. Courtney2 1 Northern Ireland Blood Transfusion Service (NIBTS), and 2Belfast Trust, UK

Introduction: The Northern Ireland renal transplant programme has received additional funding for living donor transplants. Sources of organs historically have included cadaver, deceased cardiac dead and deceased brain dead. This has limited available organs and led to longer waiting lists for patients. Up to 50 living donor transplants, mostly from altruistic non-related donors but also family donors have now been completed. Laboratory Testing: The Northern Ireland Blood Transfusion Service supports this programme by undertaking serial anti-A and anti-B titration studies for major ABO mismatched donor recipient pairs. The laboratory protocols are described. Clinical Management and Patient Outcomes: Selected case studies are described where the laboratory results have informed clinical management decisions and patient outcomes are also included.

PO76 Reducing Wastage Level of Paediatric Blood Units A. Allameddine, H. Morris, M. Heaton, H. Jenkins & S. Flynn The Pennine Acute Trust, Manchester, UK

Introduction: A certain level of blood products wastage is often inevitable, especially those with short shelf life and needing to be readily available when necessary. The current practice in issuing anaemic neonates with ABO RhD matched red cells has resulted in high wastage level of paediatric units, issued as ‘paedipacks of 60 . In an attempt to reduce this wastage, a decision was made to issue all neonates with O RhD Negative units and limit the number of packs issued in proportion to gestational age. Study Design: The proposed change was agreed with neonatal team and introduced in December 2013. All new requests were issued with O RhD Negative blood with the number of units issued dependent on gestational age; a complete set of six paedipack units for neonates 28. Results: The number of paediatric units wasted between January– April 2014 was 69 units compared to 149 in the same period of 2013. This corresponds to 46% reduction in paediatric blood wastage with positive impact on stock availability, resulting in reduction on Ad-hoc deliveries required from NHSBT. The change in practice has, however, resulted in extra sampling for discrepant groups where these were different from the original. The sample groups were either O RhD Negative or mixed field. This has required training for staff in understanding the reason for these discrepancies and how to resolve them on the Autoanalyser and host computer system. Conclusions: The change in practice has successfully achieved the aim in reducing the wastage of paediatric blood units. The saving is equivalent to an average of £967 per month.


PO78 Varying Ability of Monoclonal Anti-D Reagents and Weak RhD Discrepancies- Our Experience J. Jeyachandran,1 E. Li,2 R. Rady,2 A. Vintila2 & A. Humayun2 1

Burton Hospitals Foundation Trust, and 2Burton Hospital NHS Foundation Trust, UK Rh is one of the important blood group system and D antigen is the most immunogenic and clinically significant because of the ability to cause haemolytic disease of new born and transfusion reactions. The monoclonal anti-D reagents used to detect D antigen vary widely in their ability to detect both partial and weak D but can detect the weakest Rh D type. Variation of clones used in the monoclonal antiD reagent may cause discrepancies when variant D is detected. Recently as part of our cost saving measure we introduced the use of DiaClon ABD (DVI-) confirmatory cards for patients with a known historical blood type but the different clone of monoclonal anti-D reagent used in the confirmatory card led to significant discrepancies between the historical and current RhD type on weak RhD patients. In order to assess the level of discrepancy on weak RhD patients a prospective audit was carried out from 01.11.2013 to 30.04.2014 on all samples that were reported RhD weak positive and on samples that did not match the historical RhD type. All antenatal samples which gave a weak reaction were referred to NHSBT for confirmation. 23 samples were identified to have weak RhD type and out of the 23 samples 3 did not have previous history therefore it was excluded from the study. Out of the 20 samples 6 (30%) gave a discrepant RhD type. Four of them gave RhD positive result and 2 of them Rh D Negative results. The samples which gave a negative result were referred to NHSBT and confirmed as Weak RhD type. Conclusion: Our audit shows significant discrepancies between the monoclonal reagents used and highlights the need for manufacturers to standardise the monoclonal reagents to minimise the weak RhD type discrepancies


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PO79

PO80

Reducing Out-of-Hours Transfusions – a Hospital Education Campaign

The Impact of Electronic Decision Support and Electronic Remote Blood Issue on Transfusion Practice

J. McCullough, K. Robinson & A. Nicolle

S. Hibbs,1 M. Murphy,2 S. Noel,3 D. Miles3 & J. Staves3

Queen Elizabeth Hospital (QEH), Gateshead, UK

Background: Guidelines published by Serious Hazards of Transfusion (SHOT) recommend that out-of-hours transfusions ‘should be avoided unless clinically essential’ as they carry a higher risk to patients. An initial audit of out-of-hours transfusions at the QEH showed a significant number of non-essential transfusions overnight. The audit was repeated following an education campaign in the hospital. Methods: A two cycle prospective study of all transfusions performed out-of-hours (20:00–08:00) at the Queen Elizabeth Hospital. During the first cycle (6/1/14–6/2/14) information from patients’ notes and pathology e-records were collated using a standard proforma and the transfusions were categorised according to clinical need. Results of the first cycle were presented to the hospital transfusion committee who implemented the following interventions: 1. Emphasis of SHOT guidance at all staff mandatory training. 2. Circulation of audit results and SHOT guidance to lab staff and all doctors via email and posters. 3. Junior doctor transfusion education sessions and discussion of audit results. 4. Senior nursing staff contacted on all wards to ensure staff do not delay administering transfusions when prescribed. The second cycle (10/4/14–10/5/14) followed the same methodology as the first.

Results: Of 61 transfusion episodes during the 1st cycle: 1. 1.28 (46%) met SHOT guidance. 2. 2.23 (38%) were inappropriate. 3. 10 (17%) had no recorded reason for transfusion.

1 University of Oxford, 2National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford University Hospitals and the University of Oxford, and NHS Blood & Transplant, and 3Oxford University Hospitals NHS Trust

Objectives: To assess the impact on transfusion practice of a two stage electronic intervention: the introduction of a decision support system (DSS) followed by the addition of electronic remote blood issue (ERBI). Background: With increasing evidence to show the benefit of restrictive transfusion policies, it is important to ascertain which interventions can increase clinician compliance with their implementation. A DSS provides patient-specific recommendations to clinicians. ERBI reduces delays in acquiring blood and may alter the transfusion behaviour of clinicians. Methods: All electronically requested blood transfusions administered outside of surgical theatres or recovery were identified in a specialist orthopaedic hospital. These were divided into three time periods corresponding to pre-intervention, the successive introduction of DSS alone and DSS with ERBI. Pre- and post-transfusion haemoglobin concentration (Hb) levels, and the number of units ordered and transfused were recorded. Results: 204 transfusions for 92 patients were assessed. 38/85 (45%) transfusions in the first time period were compliant. This did not significantly change after introduction of the DSS, but with DSS and ERBI together significantly increased to 39/60 (65%) (P < 0.05). Mean pre-transfusion Hb reduced from 8.24 g dL1 in the first time period to 7.67 g dL1 in the third (P < 0.0001). There was no significant change in overall blood usage, although ERBI significantly reduced the amount of unused blood orders from 70 to 25%. Conclusion: Electronic DSS may not be sufficient to change practice without training, education and feedback. ERBI can contribute to significant improvements in blood usage as well as the efficiency of blood provision.

Of 25 transfusion episodes during the 2nd cycle: 1. 22 (88%) met SHOT guidance. 2. 3 (12%) were inappropriate. 3. 0 (0%) had no recorded reason for transfusion.

Conclusions: 1. The above interventions were straightforward to implement and achieved a substantial reduction in the number of out-ofhours transfusions (from 61 down to 25). 2. A much greater proportion of out-of-hours transfusions now comply with SHOT guidance (88% compared to 46%). 3. The investigators are aware that this education campaign will need to be repeated for each new intake of junior doctors.



XXXII Annual Scientific Meeting of the British Blood Transfusion Society 63

POSTER SESSION MICROBIOLOGY

PO81

PO82

Hepatitis E Exposure in Blood Donors in Upper Austria

Prevention of Post-Transfusion Hepatitis C by Screening of Antibody to Antigens in Blood Donors

C. Gabriel, C. Fischer, M. Hofmann, K. Hofer, J. Kaar & I. Bartl Red Cross Transfusion Service for Upper Austria, Linz, Austria

Background: In recent years different studies showed that hepatitis E virus (HEV) is a growing public health concern in many developed countries. Therefore, HEV infections might bear a risk for transmission via blood transfusion and the clinical relevance of transfusion transmitted HEV infections still requires further investigations (1, 2). The aim of this study was to get an overview of acute HEV infections in Upper Austrian volunteer blood donors as well as occupational risk in transfusion-related infections. Materials and Methods: Anti-HEV antibodies were detected by WanTai anti-HEV IgM and IgG assay. HEV RNA was extracted from 1 mL EDTA plasma from pools of 96 blood donations by using Magna Pure Compact Nucleic Acid Isolation Kit I (Roche Diagnostic). Amplification and detection was performed using RealStar HEV RT-PCR Kit (Altona Diagnostics). Additionally, HEV positive samples were genotyped by sequencing the ORF1 or ORF2 region. Results: We investigated the prevalence of anti-HEV IgG in Upper Austria in 1203 random blood donors collected between October 2013 and January 2014. 13.55 % showed positive results for antiHEV IgG. Furthermore, a total of 58,915 individual blood donors were tested for HEV RNA between February 2013 and April 2014. Seven of these donors (0.01%) were PCR-positive without pathological findings. All HEV RNA positive donor samples were genotyped and revealed genotype 3 isolates. Viral load based on quantitative real-time PCR was calculated and corresponds to a HEV nucleic acid concentration of 2217–293,635 IU mL1. Serological testing revealed that all donors were seronegative for HEV IgM or IgG antibodies at time of donation, but after 6 weeks antibodies for anti-HEV IgM and anti-HEV IgG were detected. No donor developed a chronic course of the disease. Conclusions: In the presented study we investigated HEV infection in blood donations of Upper Austria over 1 year. We figured out that 1 of 8416 blood donations is HEV RNA positive. Seroprevalence of anti-HEV IgG results in an age-related increase of 13.55%. Therefore, based on this data we recommend HEV-PCR screening to prevent transmission of hepatitis E virus by transfusion. References 1. Huang FF, Haqshenas G, Guenette DK, Halbur PG, Schommer SK, Pierson FW, Toth TE, Meng XJ. Detection by reverse transcription-PCR and genetic characterization of field isolates of swine hepatitis E virus from pigs in different geographic regions of the United States. J Clin Microbiol. 2002 Apr; 40(4):1326-32. 2. Dalton HR1, Bendall R, Ijaz S, Banks M. Hepatitis E: an emerging infection in developed countries. Lancet Infect Dis. 2008 Nov; 8 (11):698-709.


I. Naseer, A. Naz, B. Kumar Sil, S. Naz Mukry, I. Shamim, K. Naseem & T. Sultan Shamsi National Institute of Blood Diseases & Bone Marrow Transplantation, Karachi, Pakistan

Background: Transfusion-associated hepatitis C virus (HCV) infection in patients suffering from blood disorders continues to be a major problem in Pakistan. Post – transfusion hepatitis C infections can be controlled by pre-transfusion screening of donors for antibodies against HCV. Objective: Evaluate the efficiency of anti- HCV antibodies by solid-phase immune-chromatographic assay compared with standard quantitative laboratory test and qualitative reverse transcriptase polymerase chain reaction (RT-PCR). Methodology: Total 6000 healthy male donor’s blood samples were screened for anti-HCV assay using chemiluminesence technique, Abbot ARCHITECT. Later all 200 anti-HCV reactive samples were tested for RT-PCR to detect the presence of nucleic acid, two HCV screening ELISAs (Monolisa Anti-HCV Plus V2 and AntiHCV-MPBIO-EIA) and HCV supplementary Assay (MPD HCV Blot 3.0). The performance of MP MULTISURE HCV Antibody Assay (immune-chromatographic device) was conducted using HCV true positive and negative samples. MPD MULTISURE HCV Antibody Assay was developed for the detection and differentiation HCV antibodies into core, NS3, NS4 and NS5. Results: A total of 200 blood donor’s samples were selected for this study, of which 127 samples were considered as HCV positive (100 HCV Nucleic acid test positive and 27 samples positive with three HCV screening assays) and 22 samples were found to be negative to HCV antibodies (negative with screening assays and HCV Blood). The solid-phase immune-chromatographic device MULTISURE HCV Antibody Assay detected 95.49% (95% CI: 88.97–97.76%) HCV positive cases while all 22 HCV antibody negative samples were found to be negative with the test (100% specificity 95% CI: 84.56– 100.00%). The positive and negative predictive values were 100% (95% CI: 84.56–100.00%) and 75.86% (95% CI: 56.46–89.70%) respectively. Of seven MULTISURE HCV Antibody Assay negative samples, two samples were found to be negative with HCV-NAT assay and could be true negative. Conclusion: The newly introduced MPD MULTISURE HCV Antibody Assay device was intended to serve as a simple and easy to use rapid test for screening of HCV infection in emergency situations. The cost of assay will be cheap, sensitivity and specificity wise it is comparable with HCV screening assays and can be used at all levels of the health care system. More precisely, the test will be more accurate as it can detect more than one HCV antibody from the suspected patients.


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PO83 Transfusion Transmitted Infections Among Blood Donors of Bone Marrow Transplant Patients A. Naz & I. Naseer

Conclusion: In a developing country like India where cost is an important factor, blood wastage due to contamination should be minimized. Hence implementing the above strategies has helped us in reducing discard of blood products due to contamination and enhanced availability of blood products to patients at our hospital

National Institute of Blood Disease and Bone Marrow Transplantation, Karachi, Pakistan

Background: Large numbers of blood donors are required in Bone marrow transplant patients. Donor selection is important because infected individuals serve as an asymptomatic reservoir and a potential source of transmission. Objective: To investigate the prevalence of syphilis, viral (Hepatitis B virus, Anti-HCVand Anti HIV) and parasitic infections among the blood donors of bone marrow transplant patients. Methods: A retrospective study was carried out at national institute of blood disease and bone marrow transplant center during August 2008 to May 2014. Blood donors were screened through detailed standard questionnaire and their blood samples were tested for parasitic infections using peripheral film, syphilis, Hepatitis B, C and Human immune deficiency virus using chemiluminesence, Abbott ARCHITECT. Statistical analysis was done by SPSS Version 17.0. Result: Out of 36,000 blood donors, mean prevalence of HBs Ag (2.7%), anti-HCV (3.2%), anti- HIV (0.01%), HBV+HCV co-infection (2.6%), Syphilis (0.15%), malarial parasite (0.09%) and Microfilaria (0.005%) was recorded. Conclusion: Highest incidence of single infections of HCV, HBV and co-infections were found. Urgent and concrete measures are needed to eliminate the paid blood donations.

PO84 Strategies to Minimize Bacterial Contamination of Blood Products in a Developing Country A. Anandan,1 K. Radhakrishnan2 & V. Kumar Panicker2 1 Department of Transfusion Medicine, and 2Sri Ramachandra University, Chennai, India

Body: Bacterial contamination of blood products is second to ABO incompatibility as a cause of death due to transfusion. The contamination is thought to occur primarily during phlebotomy. Bacterial contamination is seen more with platelets because of room temperature storage. Blood wastage is also increased due to contamination. The aim of the study was to implement strategies to reduce bacterial contamination of blood products. This study was conducted in the Department of Transfusion Medicine at a tertiary care hospital in India during the period January 2012–January 2014. During the period January 2012– January 2013, blood bags without diversion pouches were used for collection. Total number of donations were 12,249 of which 2 bags were sent for culture daily as a quality control measure. Out of the 730 bags sent for culture, 10 bags showed growth for bacterial contamination that is 1.36%. The strategies implemented were stringent donor examination regarding donor health status, proper donor arm preparations and use of blood bags with diversion pouches and platelet collections by apheresis. All blood bank staff and technicians were educated and trained for proper donor arm preparation as per AABB standards and blood bags with diversion pouches were made mandatory. A total of 108 Apheresis platelets were collected and no bacterial growth was seen on culture testing. After implementing these in 2013, the total number of donations were 13,667 of which 2 bags were sent for culture daily. Only 5 of the 730 bags (0.68%) showed bacterial growth after following new protocols.


PO85 Bacteriological Monitoring Investigations C. George & S. Pearce Welsh Blood Service, Wales, UK In May 2012 the Medicines and Healthcare products Regulatory Agency (MHRA) released guidance on the ‘Minimum Expectations for the Management of the Outcome of Bacterial Monitoring Investigations and reporting requirements to SABRE’. The guidelines sought to define a comprehensive and structured approach to investigations of positive culture results from platelet bacterial monitoring programs. The Welsh Blood Service (WBS) has been performing bacteriological monitoring on 100% of platelets produced since 2003. Following release of the guidelines, a gap analysis was undertaken on the current investigative and recall procedures. Several areas were identified for improvement: 1. Formalising the investigation process 2. Ensuring Timelines for recall of products were met 3. Aligning the Quarantine procedure with the new processes The procedures for investigation of bacterial processes were updated to meet the guidelines. To achieve this two levels of investigation were set depending on the type of positive result received. When the result is classified as a ‘False Positive’ or as an ‘Unconfirmed Positive’ then no further investigation is required. When the result is classified as a ‘Confirmed Positive’ or ‘Indeterminate Positive’ an investigation is initiated. If the organism identified is likely to be pathogenic then a full investigation is carried out. The recall procedure has been amended to record the time of the initial positive result, the time the unit was removed from the supply chain and every time a recall is performed it must be confirmed that it was within the 1 h time limit. If the Quality Systems fail then this would be reported to the MHRA using the Serious Adverse Blood Reactions & Events (SABRE) system. Since the introduction of the amendments in October 2013, the WBS has had four positive pooled platelets and no positive apheresis platelets. From these, one did not require investigation, two required an initial investigation and one (confirmed Streptococcus pneumonie) required a full investigation. All investigations were completed in line with the new procedure and so far, no SABRE reports! The procedure was reviewed by the MHRA with no issues raised.

PO86 Significance of Screening Anti-HBc Among Libyan Blood Donor: A Preliminary Study M. Kaled Shambesh,1,2 E. Franka,1 F. Ismail,2,3 N. Gebril4 & K. Azabi4 1

Department of Community Medicine, Faculty of Medicine, University of Tripoli, Libya, 2National Centre for Disease Control, Libya, 3Faculty of Medical Technology, University of Omer, Almukhtar, Libya, and 4 Central Blood Bank, Tripoli, Libya

Background: The inclusion of the hepatitis B surface antigen (HBsAg) screening test for hepatitis B virus (HBV) infection in the mandatory blood donor screening programme in Libya three decades


XXXII Annual Scientific Meeting of the British Blood Transfusion Society 65 ago significantly enhanced blood safety in terms of protecting against the transmission of HBV infection; however, there may still be a remaining risk of post transfusion hepatitis B (PTHB). Several studies have demonstrated that a percentage of donors who are HBsAg negative and hepatitis B core antibody (anti-HBc) positive are carrying HBV-DNA in their blood when tested using the PCR and may be a potential source for PTHB. Objectives: This work is part of an ongoing large-scale study that aims to assess the seroprevalence of anti-HBc among healthy blood donors in Libya. Methods: 500 HBsAg negative blood samples obtained from healthy blood donors attending Tripoli central hospital’s blood bank were tested for anti-HBc using the VITROSâ 3600 Immunodiagnostic System. Results: All blood donors were male, age from 20 to 60 years, 495 (99%) were volunteer donors and 5 (1%) were replacement donors (family members, friends or relatives of the patients). The prevalence of anti-HBc in this sample of the study was 49 samples (9.8%).


Conclusion: The rate of anti-HBc among this group was (9.8%); this figure is low compared with the only available study in the region (1). However, until performing tests on a larger study sample, the study preliminarily provided an insight into the frequency of anti-HBc in blood donors and estimated the expected exclusion rate of the anti-HBc positive donated blood, which would be an important factor before adopting anti-HBc testing in addition to HBsAg testing as mandatory screening tests to further enhance transfusion safety. Later on, after completing the target sample, HBV-DNA by PCR will be performed on anti-HBc positive samples. Acknowledgement: This research is supported by the National Authority for Scientific Research (NASR). Reference 1. Ismail, F., Shambesh, M. K., Aboutwerat A. and Elbackush M. (2010) Serological and Molecular Characterization of Total Hepatitis B Core Antibodies in Blood Donors in Tripoli, Libya. The Libyan Journal of Infectious Diseases, 4, 24-30.


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POSTER SESSION PATIENT: BLOOD MANAGEMENT & TRANSFUSION ALTERNATIVES

PO87 Preoperative Anaemia and Length of Stay in Fracture Neck of Femur Patients M. Tanti, K. Gibson, J. Leong & J. Rao Countess of Chester Hospital, UK

Introduction: Preoperative anaemia is known to predict poor outcomes, but the impact of preoperative anaemia on length of stay in fracture neck of femur patients is unclear. The aim of this study was to determine whether preoperative anaemia can predict prolonged admission and to define anaemia in these patients. Methodology: All patients with fracture neck of femur admitted in Countess of Chester for the year 2013 were identified from the National Joint Registry. Pre and post operation Hb and length of stay were identified from our hospital database software (Meditech). Result: In total 289 patients with 295 procedures for fracture neck of femur were identified. The majority of patients sustained a displaced intracapsular fracture and the majority of patients required hemiarthroplasty. Preoperatively 140 (48%) patients were anaemic. The majority of anaemic patients had a normocytic anaemia (83%) and in total 100 (34%) patients required a transfusion. In this data set, preoperative anaemia was likely to be due to anaemia of chronic disease or blood loss. Pre-operative anaemia was associated with older age, female gender, and a past history of transfusion. Pre-operative anaemia was not associated with fracture severity (e.g. comminution or displacement) or mortality. Length of stay was prolonged in patients with preoperative anaemia (Mdn = 19) when compared to patients without preoperative anaemia (Mdn = 13) and this difference was statistically significant (U = 8658, P = 0.003, r = 0.17). Conclusion: Patients with pre-operative anaemia are likely to be normocytic, require blood transfusions, and have a prolonged length of stay. However, the causal factors leading to increased length of stay are uncertain, and further research with regression analyses is warranted.

Data are collected on: 1. 2. 3. 4. 5. 6.

Procedure Elective/emergency setting Equipment (‘Collect Only’ or ‘Full Processing’) Volume of ICS blood Allogeneic blood Pre/postoperative Haemoglobin

ICS can be set up as ‘Collect Only’ (C/O) (~£24) or ‘Full Processing’ (F/P) (~£78.50) (average Welsh contract prices). C/O is recommended for most elective procedures where ICS is indicated. This allows the operator to make an informed decision to proceed to F/P if sufficient blood is collected, thereby minimising wastage of consumables. 1335 cases from April 2012 to March 2013 were analysed. 140/1335 (10.5%) cases were identified where F/P was set up but no ICS blood was reinfused. 38 cases were eliminated from analysis as F/P may have been justified by other patient/procedure factors. These were: 1. Jehovah’s Witness patients (11) 2. Technical problems (6) 3. Emergency procedures (21) In the remaining 102/1335 (7.6%) cases, ICS blood was not reinfused due to: 1. Inadequate volume (72) 2. No reason stated (21) 3. Other e.g. anaesthetist decision (9) In these 102/1335 (7.6%) cases, a total possible cost of ~£5559 could have been avoided if C/O had been used. An additional 148 cases, where 1.5 L) is rare in elective category IV Caesarean sections. We did not find economic benefit for the routine use of intra-operative cell salvage in this group of patients. The mean EBL in both groups is very similar and this would suggest that an EBL greater than 1000 mL is not prohibitive for inclusion on an EROS pathway. The current recommendation of transfusion threshold of less than 75 gL1 is acceptable providing the anaemia is well tolerated. Institution of electronic cross-match in the near future will help eliminate blood wastage.

PO92 Detection and Management of Anaemia in Preoperative Cardiac Surgical Patients C. O’Donnell, E. Murray & H. Gilliland RVH, Belfast Health and Social Care Trust, Northern Ireland, UK Anaemia prior to scheduled major surgery is an independent risk factor for morbidity and mortality. If appropriately scheduled, preassessment clinics provide the opportunity to correct anaemia. In 2013, the Belfast Trust drafted new guidance on the detection and management of anaemia (1). This audit tested compliance with the guidance among cardiac surgical patients. Method: Data was collected prospectively for 100 cardiac surgical patients. Parameters measured included haemoglobin (Hb) at preassessment or on admission (if awaiting surgery as an inpatient), time between pre-assessment/admission and eventual surgery and the steps taken (if any) to investigate the cause of the anaemia or to treat it. The WHO definition of anaemia was used (Hb 99% call rate and 100% concordance of genotypes and predicted phenotypes across all six modules and independent of the different DNA sources. The entire study from buccal swab sampling through DNA isolation, Hemo ID biochemistry, data interpretation, and report generation was completed within two days. Reproducibility study: Across the three sites the observed call rates were 99.8%, 98.0%, and 99.8%. The genotype concordance was above 99%. All sites correctly identified the major and minor alleles of the interrogated blood group, including the correct identification of Rhesus negative samples, one DAU sample, two Psi variant samples, three SS samples, and one sample each that was Fy(a-b-), Js (a+b+), Co(a+b+), Yt(a+b+), and heterozygous VEL negative. Conclusion: The Hemo ID panel is a robust solution for molecular blood group genotyping. It offers high flexibility regarding DNA sampling, sample through-put, choice of blood groups interrogated, and demonstrates both excellent reproducibility between analyses and a standardized analysis and reporting software that can easily be adapted to extended, customized modules.

PO107 A New Example of Haemolytic Disease of the Newborn Caused by Anti-VONG A. McNeill,1 V. Crew,1 K. Sowinski,2 J. Daley,3 J. Curtin,4 H. Bruce,3 S. Hull,3 K. Parsons3 & N. Thornton1 IBGRL, NHSBT, UK, 2Pathology West-Westmead Hospital, Sydney, Australia, 3ARCBS, Alexandria, Australia, and 4The Children’s Hospital at Westmead Hospital, Sydney, Australia 1

Introduction: The Kell blood group system comprises 35 antigens located on the Kell glycoprotein (CD238), encoded by KEL, a 19 exon gene located on chromosome 7. KEL28 (VONG) is a low frequency antigen arising from a 742C>T mutation in exon 8 of the KEL gene, which encodes an Arg248Trp change in the Kell glycoprotein. Here we describe the second example of anti-VONG. The original VONG+ proband was described in a family of Chinese descent. Methods: Standard serological techniques and Sanger sequencing of all KEL exons was carried out. Results: Haemolytic disease of the newborn (HDN) was diagnosed in a Caucasian infant of Italian descent. The DAT was strongly positive, Hb 109 g L1, reticulocyte count 328 9 109, bilirubin 130 µmol L1. A leukoerythroblastic blood picture was noted and bone marrow suppression suspected. An antibody was found in the maternal plasma reacting moderate strength with paternal red cells. Enzyme studies showed AET and DTT sensitivity, indicating the presence of an antibody to an antigen from the Kell system. Paternal cells were found to be VONG+ with the only previously described example of anti-VONG. KEL sequencing revealed the heterozygous mutation 742C>T (Arg248Trp), associated with the expression of VONG. AntiVONG was identified in the maternal plasma, reacting with an additional example of VONG+ cells. Family studies have shown cells of the father’s grandmother, mother and sister to be VONG+. Discussion: We describe the second example of anti-VONG, diagnosed through HDN in an infant of Italian origin, and resulting from the Arg248Trp amino acid substitution in the Kell glycoprotein. We present serological and genetic evidence of the inheritance of the VONG (KEL28) antigen through three generations of the family. Despite the presence of a normal reticulocyte count, HDN due to suppression of erythropoiesis associated with antibodies to Kell system antigens, is evident in this case.


PO108 An Antibody to the Low Frequency Antigen Bea (Rh:36) Caused Hydrops Foetalis and the RHCE*ceBE Allele has been Shown to Travel With RHD*DAU-0 I. Marais,1 S. Grimsley,1 A. Millan,2 E. Muniz-Diaz,2 N. Thornton1 & G. Daniels1 1

IBGRL, NHSBT, UK, and 2Banc de Sangi, Teixitis, Barcelona, Spain

Introduction: A female patient with no previous transfusion history but two previous pregnancies presented with an antibody reacting strongly with her partner’s cells. Both pregnancies had resulted in haemolytic disease of the fetus and new-born (HDFN), with the second pregnancy affected by hydrops foetalis in week 28. Methods: Standard serological techniques, and genomic DNA sequencing were performed. Results: The patient’s antibody reacted 5+ with her partner’s cells by IAT with untreated and papain treated cells, all panel cells were compatible. Crossmatching of the patient’s plasma with the red blood cells of the partner’s family members revealed his sister and mother were also incompatible. Extensive typing with antisera to low frequency antigens identified the partner’s cells to be Be(a+) (Rh:36). Sanger sequencing of all ten exons of the RHCE gene revealed the patient’s partner, his sister and mother all have the mutation 662C>G in exon 5, encoding the amino acid substitution Pro221Arg. Discussion: This is now the third published case of anti-Bea, in all cases a non-transfused woman became sensitised during her first pregnancy and the child of the second pregnancy was severally affected by HDFN. The single amino acid change Pro221Arg appears to be highly immunogenic and sufficiently alters the Rhce protein to cause weakened expression of c and e and very weak or negative reactions with anti-f. The two previous cases were present with a cde haplotype, however sequencing of the partner and his family revealed the RHCE*ceBE allele in this case to travel with RHD*DAU-0.

PO109 Does the Sensitivity of the Pre-Transfusion Antibody Screen Affect the Incidence of Delayed Haemolytic Transfusion Reactions in Patients? J. Staves,1 S. Bradley,2 S. Harle-Stephens,3 S. Rockley4 & J. Tidman5 1 Oxford University Hospitals NHS Trust, 2Sandwell and West Birmingham Hospitals NHS Trust, 3Plymouth Hospitals NHS Trust, 4 Heatherwood and Wexham Park Hospitals NHS Foundation Trust, and 5University Hospitals Birmingham NHS Foundation Trust, UK

A representative group of five UK Hospital Trusts that use Immucor Capture-Râ Ready Screen on an automated platform (NEO or Echo analysers) as their primary serological technology for antibody screening collated their data from a 5 year period (April 2007– March 2012). Data collection included the number of red cells units issued and transfused to patients and the number of delayed haemolytic transfusion reactions (DHTRs) reported to Serious Hazards of Transfusion (SHOT). They compared their figures to those presented in the SHOT Annual reports over the same period. Previous reviews have suggested that a higher sensitivity of screening tests for red cell antibodies does not inevitably lead to improved patient safety (Issitt & Anstee, 1998). Recent SHOT report recommendations include the need for more sensitive techniques to detect Kidd antibodies and weakly developing antibodies to ensure all specificities are identified. A comparison of the performance of antibody screen techniques including microtube column systems, and solid phase systems identified Capture-R as the most sensitive of those tested (Weisbach et al., 2006). The aim of this review was to


XXXII Annual Scientific Meeting of the British Blood Transfusion Society 75 ascertain whether the use of a more sensitive antibody screening technology reduces the incidence of DHTRs. The combined data from this group represents an average of 8.21% of all NHSBT red cell issues over the reporting period, yet account for only 4.13% of all DHTRs reported to SHOT from 2007 to 2012. In 2002, SHOT reported the UK incidence of DHTRs as 1 : 70,000. The UK average incidence of DHTRs (calculated from 2007 to 2012 SHOT reports) was 1 : 33,350 per RBC issued per annum. The DHTR incidence rate for this group of hospitals was considerably lower (1 : 64,500), indicating that the risk of DHTR is reduced when antibody screening is performed using Captureâ technology. These findings support SHOT’s recommendation to use highly sensitive antibody detection methods.

PO110 RhD DAU-5 Study and Immunization M. In^es Moser,1 R. Pimentel,2 A. Alegria,3 M. J. Rodrigues,1 T. Chabert1 & M. Santos1 1

Lisbon Blood and Transplantation Centre, IPST.IP, 2Laboratorio de Analises Clınicas Dr Joaquim Chaves, Lisbon, and 3 Immunohaemotherapy Service, MAC, Lisbon

Background: The RhD variant DAU-5 of African origin, is characterized by the cDe haplotype and three SNP’s in the RHD gene. It is difficult to detect serologically as RhD typing sera give slightly weak discrepancies (3+/4+) and extended anti-D panels have the reaction patterns of Dcat V, being identified only by genetic tests. Our laboratory samples have high incidence of African individuals, and it is relevant to define their Rh status for pregnancy/transfusion proposals, specifically in DAU-5 patients usually typed as RhD positive and at risk of immunization if in contact with RhD positive blood. Aims: To retrospectively analyze anti-D immunization of DAU-5 patients and to present a specific reaction pattern with Inno-Train CDE Kit. Methods: A total of 56 DAU-5 samples (41 women and 15 men) referred by serological discrepancies (3+/4+) with anti-D sera were identified since 2007. Studies used Albaclone Advanced Partial RhD Typing Kit, UK and Diagast D-Screen, France. Genetic characterization included Inno-Train CDE Kit, Germany and sequencing of exons 1–9 of the RHD gene. Antibody screening had been performed only when requested. Results: All samples were Ror and had a DV pattern with the extended anti-D panels. The Kit was inconclusive according to the worksheet, but specific of all DAU-5 after RHD sequencing. All were DAU-5/day. Anti-D immunization was detected in two women. Conclusions: The DAU-5 is one of the most common African variants in our laboratory population, and the definition of a specific


reaction pattern with the Inno-Train CDE kit was rather important as RHD sequencing could be excluded. There are few descriptions of immunization in DAU-5 pregnant/ transfusion patients and the immunologic basis for the immune response is not known. Mostly typed as D+, the anti-D rate is low, confirmed by our study where from a total of 41 women only 2 were immunized

PO111 Identification and Exclusion of Problematic Red Cell Antibody Screening Cells Expressing HLA S. Bull,1 M. Weston,2 K. Singh2 & V. Sowden2 1 NHSBT, Liverpool, and 2NHSBT, UK

Introduction: A quantitative assay of HLA expression on RBCs has been developed, with the intention to exclude red cell antibody screening cells that react with HLA antibodies. This flowcytometry method is more sensitive than a haemagglutination assay. In June 2012 NHSBT Reagents started to exclude screening cells based on this assay. Here we present data from the first 18 months. Method: Anti-HLA FITC (W6/32) and isotype control were incubated with RBCs. and analysed on a flowcytometer. All tests were run in duplicate with 5 control cells. Results: 424 donations from 317 donors were tested. All RBCs expressed some HLA antigens, with the majority (86%) expressing antigens at levels not detectable in haemagglutination assays. 62 potential screening cell donations (14%) were excluded. The number of customer complaints relating to HLA activity on screening cells fell from 47 to 6 in the corresponding time period. Variation in HLA antigen expression shows a skewed normal distribution, the majority of cells (96%) falling within the bell shaped curve. The high expressors were up to 8 times the mean, with one Bg(a+) cell 28 times higher. 48% of donors, showed a significant difference in HLA expression between different donations. Conclusion: All RBCs express HLA antigens, the majority of cells have levels undetectable by haemagglutination tests. The expression of HLA antigens above a threshold value, determined by controls, can be used to identify potential problem cells. Introduction of this assay at NHSBT Reagents has led to a significant reduction in the number of related customer complaints and the number of resulting product recalls, with an estimated financial saving to NHSBT of £12,000 per annum. The HLA expression on RBCs from a donor can vary considerably over time (up to 800%) which explains the previously reported phenomenon of donor RBCs changing from HLA positive to negative and vice versa.
