disorder of skeletal muscle. The syndrome is characterized by muscle cramps, myoglobinuria, and a grossly elevated serum creatine kinase. The most common ...
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REFERENCES 1 American Academy of Pediatrics. Guidelines for prevention of group B streptococcal (GBS) infection by chemoprophylaxis: Committee on Infectious Diseases and Committee on Fetus and Newborn. Pediatrics 1992;90:775-8
2 Maak B, Muller E, Berbig H, Estel C. Maternal deficiency of IgG2 and IgG4 and neonatal infection caused by B-streptococci. Zentralb Gynakol 1993;115:136-9
Idiopathic rhabdomyolysis J Fraser MRCP1 R Barfoot MSc1
S Fang PhD MRCP1 P T Clayton MD MRCP2
J R Soc Med 1996;89:706-707
SECTION OF PAEDLATRICS, 28 FEBRUARY 1995
Idiopathic rhabdomyolysis is a rare and potentially lethal disorder of skeletal muscle. The syndrome is characterized by muscle cramps, myoglobinuria, and a grossly elevated serum creatine kinase. The most common cause of mortality is acute tubular necrosis. The key to successful management is early recognition and prompt treatment. CASE HISTORY
A boy presented at 2 years 5 months with a history of coryzal symptoms for 1 week and diarrhoea and vomiting for 24 h. On the morning of admission he had passed red urine. His older sister had died in 1991 aged 5 years following a similar illness. On examination he looked mildly dehydrated and pale. His weight was 12.1 kg (10th centile), blood pressure 110/60 mmHg and heart rate 110 bpm. His calf muscles were tender on palpation. Routine blood investigations were normal. Urine analysis demonstrated a large amount of a pink coloured protein and electrophoresis showed this to be myoglobin. His serum creatine kinase was grossly elevated at 135 000 U/L. Therefore a diagnosis of rhabdomyolysis was made. He was initially rehydrated with 4.5% albumin and dextrose saline before being transferred to the metabolic unit at Great Ormond Street Hospital for further investigation. The results of the following investigations were normal: quantitative plasma free and acyl carnitine; blood spot acyl carnitine profile; plasma amino acids and urine organic acids; G6PD assay; red cell glycolytic 'Department of Paediatrics, Whipps Cross Hospital, Whipps Cross Road, London Ell 1 NR; 2Metabolic Unit, Great Ormond Street Hospital, Great Ormond Street,
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London WC1 N 3JH, England
Correspondence to: Dr J Fraser
Volume 89
December 1996
3 Larsen JW, Dooley SL. Group B streptococcal infections: an obstetrical viewpoint. Pediatrics 1993;91:148-9 4 Noya FJ, Baker CJ. Prevention of group B streptococcal infection. Infect Dis Clin N Am 1992;6:41-55 5 Simpson AJH, Mawn JA, Heard SR. Assessment of two methods for rapid intrapartum detection of vaginal group B streptococcal colonisation. J Clin Pathol 1994;47:752-5 6 Jones DE, Kanarek KS, Lim DV. Group B streptococcal colonization patterns in mothers and their infants. J Clin Microbiol 1984;20: 438-40
intermediates; and the ratio of non-esterified fatty acids to ketones after a prolonged fast. A needle muscle biopsy showed no evidence of MacArdle's disease or phosphofructokinase deficiency but it did show a mild increase in lipid. This might suggest a disorder affecting fatty acid oxidation in muscle, though as yet we have been unable to prove this. Our patient did not have the fasting hypoketotic hypoglycaemia and elevated plasma free carnitine typical of carnitine palmitoyl transferase 1 (CPT 1) deficiency. Nor did he have the pattern of acyl carnitines in the blood that indicates CPT2 deficiency, long chain acyl CoA dehydrogenase deficiency or other known defects of fl-oxidation. The patient improved clinically over the next few weeks. His renal function was normal. His serum creatine kinase had returned to normal and his urine had become negative for myoglobin by week 3. It is suspected that his sister died of the same disorder although post-mortem examination was inconclusive. Since the whole episode was precipitated by a period of fasting associated with an intercurrent illness, the family have been advised during periods of illness never to allow fasting for longer than 6 h and have been provided with an emergency pack of 15% Maxijul.
COMMENT
Idiopathic rhabdomyolysis was first described in 1910 by Meyer-Betz in a 12-year-old boy who suffered three attacks of muscle cramps associated with weakness and pigmenturial. Two forms of the disease have been described. Type 1 is usually precipitated by exercise and type 2 by infection or fever. The type 1 exercise-induced form is characterized by a male predominance, more frequent attacks, and a lower morbidity and mortality. The type 2 toxic childhood form is seen equally in boys and girls and is characterized by fewer but more severe attacks, and a higher morbidity and mortality. The likelihood of identifying an underlying biochemical defect remains low. Disorders of both fatty acid oxidation and glycolysis/gluconeogenesis may result in myoglobinuria. In a literature review of 60 cases between 1910 and 1988, only 18 cases were fully characterized2. Of these, 11 were due to CPT deficiency and seven to glycolytic defects.
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Management in the acute stage includes prompt fluid replacement to prevent the onset of acute tubular necrosis3. Many specific treatment modalities have been tried, generally without success. No doubt as more specific metabolic defects are discovered then more rational therapeutic options will follow. The development of specific genetic probes may allow for prenatal detection and for screening of carriers.
OF MEDICINE
Volume 89
December 1 996
REFERENCES I Savage D, Forbes M, Pearce GW. Idiopathic rhabdomyolysis. Arch Dis Child 1971;46:594-607 2 Tein I, DiMauro S, DeVivo D. Recurrent childhood myoglobinuria. Adv Paediat 1990;37:77-117 3 Milne C. Rhabdomyolysis, myoglobinuria and exercise. Sports Med 1988;6:93106
Multiple myeloma presenting as recurrent ureteric obstruction J Weir BSc MB
F A W Schweitzer FRCS
J R Soc Med 1996;89:707
A patient with unexplained radiolucent stones requires further investigation, as illustrated by the following case. CASE HISTORY A 51 -year-old man presented with a short history of left renal colic, anaemia and deteriorating renal function (creatinine 505 mmol/L, urea 18 mmol/L). He had been seen on two other occasions over the previous year with left renal colic and each time had successfully passed a stone. Radiological assessment suggested a radiolucent stone in the upper left ureter. Protein analysis of the urine and serum electrophoresis revealed BenceJones protein and a dense band of kappa light chains. Skeletal survey showed multiple lytic lesions in the humerus (Figure 1), skull and femora. Bone marrow trephine showed 30% plasma
cells, confirming the clinical diagnosis of multiple myeloma. The stone was removed by open ureterolithotomy and a concurrent renal biopsy revealed extensive tubular damage with cystic dilation due to cast formation typical of myeloma. His renal function improved after removal of the stone and initial chemotherapy. COMMENT Urinary tract obstruction is rare in patients with myeloma and is usually due to uric acid calculil. However, renal impairment is present in nearly 50% of patients with multiple myeloma, and is an important prognostic Department of Urology, Royal Surrey County Hospital, Guildford, Surrey, England
Correspondence to: Dr Weir
Figure 1 Multiple lytic lesions in the shaft of the right humerus
indicator2. In this case the deposition of light chains within the tubules was also the cause of his chronic renal failure rather than just the obstructive uropathy. Prevention of dehydration, hypercalcaemia and infection which can precipitate acute renal failure are important in myeloma patients3. This report highlights the need to consider the diagnosis of multiple myeloma in any patient who presents with unexplained radiolucent stones. REFERENCES I Faber M, Nairns R. Insidious renal failure. Hosp Pract 1992;27: 159-76 2 Warwicker P, Sumerfield G, Cove-Smith R. Management of the patient
with multiple myeloma and renal failure. BrJ Hosp Med 1994;51:582-8 3 Martinez-Maldonado M, Yium J, Suki WN, Eknoyan G. Renal complications in multiple myeloma: pathophysiology and some aspects
of clinical management. J Chron Dis 1971;24:221-37
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