Introduction Conclusion Patients and methods ...

Horseshoe Kidneys in Childhood Are They More Than Incidental Findings ? Warne SA, Dhillon HK, Mushtaq I, Smeulders N, Cuckow P, Ransley PG, Duffy PG, Cherian A Department of Paediatric Urology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK

Introduction

Outcome at long-term follow-up

Horseshoe kidney(HSK) occurs in 1 in 400 births and is the most common renal fusion anomaly. The aim of this review was to determine the presentation, associations and long-term outcome for patients with HSK diagnosed in childhood.

• VUR resolved on Mag3 IRC in all patients by age 7.

Patients and methods Between 1985 and 2005, 102 patients were diagnosed with horseshoe kidneys at our institution. Pre and postnatal history were recorded and radiological investigations included ultrasound scan (US), cystogram, and isotope renogram (Mag3/DMSA) at presentation.

• Simple HSKs remained normal throughout the follow-up period.

Figure 1 - DMSA for patient with uncomplicated HSK

Results 73 boys and 29 girls were reviewed and followed up for 5-20 years (mean 13 years). HSK was suspected on presenting ultrasound but diagnosis was confirmed by isotope renogram in all. The majority of HSKs were diagnosed in the neonatal period: 34/102(33%) following abnormal prenatal scans and 34/102(33%) in patients Figure 2 - HSK with Wilms’ with associated anomalies where HSK tumour was detected co-incidentally by screening ultrasound scan. Two patients had HSK diagnosed as co-incidental finding during spinal surgery. A third of the group 32/102 presented with symptoms (commonly UTI, abdominal pain, haematuria) aged 2-15 (mean 8.8) years. Presentation Prenatal diagnosis

34 (33%)

Co-incidental finding (US for associated anomalies)

34 (33%)

Co-incidental surgical finding

2 (2%)

Symptomatic

32 (32%)

Table 1 - Mode of Presentation of HSK A simple (uncomplicated) HSK was diagnosed in 35(34%). Abnormalities or anomalies on ultrasound scanning at presentation are highlighted in Table 2. Duplex systems were diagnosed in 7 patients (8 renal units). In the symptomatic group 2 patients were diagnosed with Wilms tumour and 2 had renal calculi. A cystogram was performed in 52 patients with hydronephrosis or dilated ureters. Vesicoureteric reflux (VUR) was diagnosed in 14 patients (bilateral in 5) and 7 had ureteric dilatation. Ultrasound findings at presentation Simple Horseshoe kidney

35 (34%)

Single moiety hydronephrosis

41 (40%)

Bilateral hydronephrosis

12 (12%)

Multicystic Moiety

7 (7%)

Duplex Systems

7 (7%)

Table 2 - Ultrasound findings for 102 patients suspected HSK at presentation HSK was an isolated clinical finding in 54/102(53%) of patients whereas 48/102(47%) had additional associated anomalies including: VACTERL association in 10, spina bifida in 9, Turner’s syndrome in 6, cardiac anomalies in 6, posterior urethral valves in 3, DSD in 3, undescended testes in 3, telangiectasia in 2, neurofibromatosis in 2, hemihypertrophy 1, Opitz G syndrome 1, CHARGE association in 1 and Denys Drash in 1.

• The cystic dysplastic moiety resolved in 6 patients and 1 required intervention for hypertension. • Surgical intervention was required in 17/32 (53%) of the symptomatic group and the remainder remain under review.

Figure 3 - CT with 3D reconstruction illustrating left PUJ obstruction

• Surgical intervention was required in 10/34 (29%) of the prenatally diagnosed patients. • None of the HSK kidneys detected co-incidentally by ultrasound screening required an intervention • None of the group developed renal impairment Surgery Surgical intervention

No

Pyeloplasty

16 *

Pyelopyelostomy

2

Heminephrectomy

5

Wilms Tumour nephrectomy

2

PCNL

1

ESWL

1

Total

27 (26%)

*18 renal units Table 3 - Surgical procedures performed in 27 patients

Conclusion Hydronephrosis was a common finding in our series of HSK patients and was detected in half at presentation. Surgical intervention in childhood was required in a quarter. Simple HSKs remained stable during follow-up.