The postnatal management of boys in a national cohort of bladder outlet obstruction.

AIM: The most common cause of congenital bladder outlet obstruction (BOO) is posterior urethral valves (PUV). Initial treatment requires decompression, but transurethral incision (TUI) or primary diversion is all described. There is no randomized control trial to guide management. This study aims to describe management, circumcision, and UTI rate in a national cohort of PUV boys. METHODS: Boys diagnosed with BOO were recruited (via BAPS CASS) over 1 year with ethics committee approval (ref: 12/SC/0416). Data were collected via questionnaire, presented as number (%), analyzed by Mann-Whitney/chi-square/Fisher Exact tests, and p < 0.05 was taken as significant. RESULTS: BOO presented in 121 boys during 2014-2015, and 113 were PUV. Catheter placement in 87/121(72%) was more likely to happen in antenatal vs. postnatal vs. late(>1 y) presentations, p < 0.0001. Polyuria occurred in 23/45(51%), 12/48(25%), 0/28(0%), respectively, p < 0.0001. Initial surgical treatment was TUI in 108/121(89%) and vesicostomy in 2. Two ureterostomies were secondary procedures. Circumcision was performed in 52/121(43%) in antenatal presentation vs. postnatal vs. late 27/45(60%), 20/48(42%), 2/28(7%), respectively, p = 0.01. 69 UTIs occurred in 49 patients. Circumcision was associated with an 86% reduced risk of UTI, p < 0.0001. There was a 66% reduction in UTI risk associated with TUI alone, p < 0.01. There was 1 death due to pulmonary hypoplasia and renal failure, and 2 experienced end-stage renal failure (ESRF). CONCLUSION: Standard treatment for BOO and PUV in the current UK cohort is urethral catheterization followed by TUI. Supravesical diversion is a rescue therapy. UTIs are common and reduced by circumcision, with 43% being circumcised. Initial mortality rate was 1%, and 1.6% present in ESRF. LEVEL OF EVIDENCE: Prognostic study - Level I - Prospective National Cohort Study.

Current epidemiology and antenatal presentation of posterior urethral valves: Outcome of BAPS CASS National Audit.

AIM: Posterior urethral valves (PUVs) are the most common cause of congenital bladder outlet obstruction (BOO) in boys and end-stage renal failure (ESRF) in childhood. In the 1980s, 1 in 4000 boys had PUV. Presentation was 1/3 antenatal/neonatally, 1/3 postnatal, 1/3 late (>1 year). This study aimed to describe the current proportions in a contemporary cohort. METHODS: A national audit (BAPS CASS) of referrals in the UK and Ireland of boys diagnosed with suspected or confirmed PUV in a year was conducted. National registration data provided the male birth-rate. Data were presented as number (%), analysed by Mann-Whitney U-test and Chi-square test, with P < 0.05 taken as significant. The study was approved by a national ethics committee (NRES Committee South Central Oxford A (12/SC/0416)). RESULTS: Data were collected from 1st October 2014 to 30th September 2015 from 25/26 centres on 121 cases of suspected bladder outlet obstruction (BOO), of which 113 (93%) were because of PUV. The male birth rate during the period was 432,806/year. The calculated incidence of BOO was 1/3580 and for PUV was 1/3800 per-annum. The proportion of PUV presenting according to age was: antenatally (n = 40, 35%), infancy (n = 47, 42%), and late (n = 26, 23%). Plasma creatinine was higher in antenatally-diagnosed BOO vs. postnatal, 54 (39.5-109.5) µmol/l vs. 34(21-47) µmol/l, P = 0.0005. Hydronephrosis and ureteric dilatation were significantly greater in antenatally diagnosed BOO vs. postnatal vs. late. Renal dysplasia (cortical thinning, poor corticomedullary differentiation, or renal cysts) was significantly more likely in antenatally diagnosed BOO. CONCLUSION: Neither the incidence (~1/4000) nor the proportion antenatally diagnosed (~1/3) of boys with PUV appears to have changed in the past 30 years. Those boys who were antenatally diagnosed have significantly higher postnatal plasma creatinine, more hydroureteronephrosis, and renal dysplasia than those diagnosed in infancy or later. It may be hypothesized that this is the reason they are detected antenatally. LEVEL OF EVIDENCE: Prognosis study - Level I - prospective national cohort study.

Bladder augmentation in anuric/defunctioned microbladders and a novel antireflux mechanism for Mitrofanoff anastomosis to the ileal patch.

BACKGROUND/PURPOSE: Reconstruction of microbladders is a difficult surgical challenge: How can a neobladder be recreated when >90% of the new bladder is augmented patch, and how can a Mitrofanoff conduit be anastomosed when the native bladder is so tiny? This series describes microbladders secondary to anuria and/or diversion that required augmentation. This was done using a de-tubularized ileal segment, and because of the small size of the native bladder, Mitrofanoff anastomosis was performed to the bowel patch (using a novel "Keel Procedure"). METHODS: Our surgical experience in reconstruction of microbladders was reviewed: pre and post augmentation capacity, compliance and maximum detrusor pressure were compared. The success of the Mitrofanoff anti-reflux technique is described. Data are given as median (interquartile range) and compared by Wilcoxon paired rank test. RESULTS: 10 patients, median bladder capacity pre-op 10 (9-20) mls were reconstructed. The follow up time is 2.7years (2.2-4.2). Post-op bladder capacity increased 16-fold to 167 (114-281) mls, P<0.01. Compliance significantly improved from 1.7 (0.3-4.8) to 14.3 (4.1-66.3) mls/cmH2O, P<0.05. Maximum detrusor over-activity decreased from 27 (7-120) to 12.5 (8-26) cmH2O, (N.S. P=0.3). Videourodynamics confirmed a leak in 2 patients, leading to incorporation into the technique of a non-absorbable seromuscular suture to provide long-term robustness to the antireflux procedure. CONCLUSION: Bladder augmentation in microbladders is possible, and a functional Mitrofanoff procedure with a continent anti-reflux procedure can be created using the "Birmingham keel technique" implanting the Mitrofanoff into the augment patch, with 80% success (similar to published results for conventional anastomosis to native bladders). LEVEL OF EVIDENCE: Level IV.