Long-term renal function and continence status in patients with cloacal malformation

Urinary continence after cloacal repair is difficult to achieve and renal outcome in patients with cloacal malformations has been scarcely reported. As a result, we reviewed our experience with cloacal malformations to determine the status of continence and the long-term renal function in these children.

A retrospective chart review from 1990 to 2003 identified 12 patients with cloacal malformation (1 posterior, 4 complex and 7 classical) who underwent surgical reconstruction. The confluence was defined as high (common channel >/= 3 cm) and low (< 3 cm) by cystovaginoscopy. Renal ultrasound, voiding cystouretrogram, renal scan and sacral radiograph were performed in all children. Most patients underwent 1-stage abdominoperineal pull-through, applying the principle of total urogenital sinus mobilization. We collected data regarding hydronephrosis, vesicoureteral reflux and split differential renal function. Renal outcome was evaluated based on glomerular filtration rate and age-adjusted serum creatinine values (mumol/L). Urinary continence was defined as a dry interval > 4 hours.

Patients' mean age at surgery was 20 months (range 7-29 mo). Of the 12 children who underwent cloacal repair, 7 (58.3%) had a common channel >/= 3cm. Renal anomalies were identified in 3 of 12 (25%) girls: there were 2 solitary kidneys and 1 pelvic kidney. Lumbar-sacral radiography demonstrated bony abnormalities in 11 of the 12 (91.6%) cases: hemivertebra in 3 cases, sacral agenesis in 4 cases, hypoplastic sacrum in 3 cases and bifid sacrum in 1 case. Total urogenital sinus mobilization through an abdominoperineal approach in a single stage was performed in 8 girls. Follow-up ranged from 4 to 14 years (mean 8.5 yr). Eight (66.6%) children had dry intervals > 4 hours, 5 (62.5%) of them were on clean intermittent catheterization through a Mitrofanoff channel and 1 (12.5%) was through the urethra. The remaining 2 (25%) patients were voiding spontaneously. Three (33.3%) patients were totally incontinent, and 1 (8.3%) patient was awaiting reconstruction. The mean measured glomerular filtration rate was 93.5 mL/min/1.73m(2) (range 34-152 mL/min/1.73m(2)). Four (57.1%) of 7 patients who had a common channel >/= 3 cm ended up needing augmentation cystoplasty, compared with none of the patients with a common channel < 3 cm (57.1% v. 0%, p = 0.038).

Urinary continence can be achieved in most patients with cloacal malformation at the expense of major reconstructive surgery and despite the presence of associated urological abnormalities. However, these children harbour an important risk for renal impairment later in life and should be closely monitored.