Clinical characteristics and kidney outcomes in children with posterior urethral valve: a single-center experience

Posterior urethral valve (PUV) represent a congenital obstructive uropathy, and despite advances in prenatal diagnosis and postnatal management, chronic kidney disease (CKD) develops in nearly 20% of affected patients. The aim of this study is to determine the clinical characteristics and kidney outcomes in children with PUV.

A total of 52 boys followed with a diagnosis of posterior urethral valves were retrospectively evaluated. Data regarding antenatal diagnosis, age at admission, and timing of cystoscopic diagnosis were recorded. Clinical and laboratory data, including serum creatinine levels and glomerular filtration rate, ultrasonographic findings, urodynamic study results, DMSA findings, and voiding cystourethrography results, were collected. In addition, lower urinary tract symptoms and the frequency of lower urinary tract infections were documented.

The mean age of the 52 patients was 9.8 ± 4.8 years, and the mean age at diagnosis was 28 ± 41 months. Antenatal diagnosis was present in 32 patients (64%) and CKD developed in 10 patients (19.2%). There was no significant difference in antenatal diagnosis rates between patients with and without CKD. In the non-CKD group, hydronephrosis grades decreased significantly at the last follow-up compared with baseline, whereas no significant improvement was observed in the CKD group. These patients had more severe and persistent hydronephrosis at final evaluation. Patients with CKD had higher ratios of increased bladder wall thickness and renal echogenicity at baseline and ureteral dilatation at final follow-up. In the baseline renal function model, baseline GFR was independently associated with CKD, but proteinuria did not retain statistical significance in multivariable analysis. There was no significant difference between groups regarding severe bladder dysfunction, DMSA renal scarring, vesicoureteral reflux grades, recurrent urinary tract infections, or incontinence.

Our findings suggest that renal damage in children with PUV may begin during the antenatal period. In this cohort, postnatal factors such as bladder dysfunction, vesicoureteral reflux, and recurrent urinary tract infections were not significantly associated with CKD. Persistent hydronephrosis at last follow-up was more commonly observed in children with CKD. In multivariable analysis, baseline renal function was significantly associated with CKD development.