BACKGROUND: Urinary diversions in posterior urethral valves (PUV) patients have been a matter of intense debate, given concerns about irreversible loss of bladder capacity due to detrusor changes triggered by a lack of bladder cycling. Despite this controversy, we have offered primary diversion in selected cases based on an established pathway to maximize upper tract drainage to prioritize preserving kidney function over theoretical bladder damage. Herein, we evaluate bladder outcomes of PUV patients managed with ablation vs. diversion.
METHODS: We reviewed our institutional PUV database between 2005 and 2024, matching patients 1:1 based on age and PURK (posterior urethral valves CKD risk) scores. Data were collected on initial surgical management, age at closure of diversion, medication use, clean intermittent catheterization (CIC), incontinence, video urodynamics (VUDS), voiding cystourethrogram (VCUG) and uroflowmetry parameters. Capacity was reported as “normal,” reduced,” or “large” based on estimated bladder capacity for age using Koff‘s formula. Cases were appropriately censored to ensure equivalent follow-up.
RESULTS: We included 57 patients managed by diversion (14 secondary procedures after failed valve ablation), matched to 57 patients with primary ablation (patient characteristics in Table 1). Vesicostomies comprised 61% of diversions, including secondary interventions. Overall, we found no difference in anticholinergic use, alpha-blocker use, the need for CIC, development of UTIs or incontinence between diversion vs. ablation groups. Importantly, we found no significant difference in bladder capacity with VUDS, VCUG or uroflowmetry parameters between diversion vs. ablation groups (Table 2).
CONCLUSIONS:
Our data indicates that bladder capacity in children managed with valve ablation is equivalent to that of urinary diversions, findings that go against some of the dogmas surrounding diversion. Concerns over bladder defunctionalization may be unwarranted and should not influence the decision to offer a diversion when objective, systematic parameters are met. The preservation of kidney function and prevention or delay in the development of chronic kidney disease should be the primary management goals of caring for children with PUV, and it seems as though this short-term, temporizing intervention carries no long-term adverse outcomes with respect to bladder dynamics.
