Patients with Prune Belly Syndrome (PBS) suffer from recurrent urinary infections, difficulties voiding/emptying and/or renal failure. Almost always, boys with PBS have bilateral undescended testis but for this article, I will only focus on the other issues.
Renal Failure, Infections, and bladder dysfunction
The renal failure is common and usually due to congenital renal dysplasia, but can also be due to recurrent infections, incomplete bladder emptying and urinary stasis in massively dilated ureters. Some articles have found the nadir creatinine in the first year to be predictive of the need for dialysis.
Urinary infections are due to incomplete bladder emptying, as well as high-grade vesicoureteral reflux and/or urinary stasis in massively dilated ureters.
Difficulties voiding/emptying arise due to poor urinary concentrating ability causing high urine output; large bladders that contract poorly; and/or urethral obstruction.
With regards to clinical interventions for these children to decrease the recurrence of infections or to prevent further renal deterioration, these can be considered:
- Prophylactic Antibiotics
- Vesicostomy or high diversion (pyelostomy, cutaneous ureterostomy)
- Reduction cystoplasty
- Bilateral ureteral reimplantation with tapering
- Abdominoplasty (to potentially create a better Valsalva maneuver to assist with bladder emptying).
- Clean intermittent catheterization
- Mitrofanoff procedure (appendicovesicostomy).
When to intervene?
Whereas the child with recurrent urinary infections likely needs something done, patients with stable hydronephrosis, stable creatinine, and no infections should probably be observed without surgery.
I think every child with PBS should be circumcised at birth to prevent UTI’s. For parents opposed to the procedure, circumcision should be strongly considered after the first UTI.
Based on the RIVUR study, antibiotic prophylaxis reduces UTI’s recurrences by 12%, but a greater benefit would be expected for patients are higher risk such as PBS boys.
Vesicostomy is an option for young sick infants (under 3 months), with recurrent UTI’s or rising creatinine, who have failed intermittent catheterization. Otherwise, complete repair could be considered for clinically stable boys older than 3 months of age.
The complete repair includes reduction cystoplasty, bilateral tapered reimplants, bilateral orchiopexy, circumcision, and abdominoplasty. An appendicovesicostomy (APV or Mitrofanoff) could also be added to the full repair.
The complete repair could help improve bladder emptying, urinary stasis in the ureters, correct VUR, and improve abdominal wall musculature to assist with complete bladder emptying and defecation. The full repair has been done in children as young as 1 month of age.
A descriptive study of the complete repair of 46 children with PBS found good results but a significant number of reoperations 37% (17/46). The authors operated in patients with significant hydronephrosis with stasis and/or VUR that presented with recurrent UTI’s. Median age at surgery was 16 months (25 days to 10 years). Ninety percent of abdominoplasties were successful and 10% were redone with a good outcome. After reconstruction, patients were kept on prophylaxis for 3 months. The authors noticed a statistically significant decrease in postoperative UTI’s, with most postoperative UTI’s asymptomatic and no cases of sepsis. With regards to to the ureteral reimplantation, VUR recurred in 15% of patients and 17% patients required revision due to obstruction. With regards to bladder reconstruction, 3 patients required an APV on subsequent follow up for bladder failure. 81% were continent after the procedure. 71% had complete bladder emptying after surgery (the others either had an APV or were doing CIC)
Another article from the Atlanta group also looked at the management of 46 patients (2 girls) with PBS. 50% of patients had bladder (vesicostomy, APV) and/or ureteral surgery and 40% underwent abdominoplasty. 17% underwent transplantation. Mean nadir creatinine was 1.4 (0.6-3) for those requiring transplantation versus 0.4 for those not requiring it. At follow up, 52% were doing CIC, 35% with APV and 17% through the urethra. Their indication for reimplantation was the presence of VUR in patients undergoing an abdominoplasty.
The latter more conservative series experienced a higher need for CIC and greater incidence of renal transplant than the former, more surgical aggressive series. Whereas the difference can be attributed to the more aggressive approach is impossible to tell given the differences in severity among patients with Prune Belly syndrome.
Some PBS patients suffer from recurrent infections and/or renal failure. These patients could be managed aggressively with a complete repair, or more conservatively with intermittent cathing/vesicostomy. The aggressive approach appears to offer a better chance of continence and preservation of renal function but the data is nowhere near conclusive.