Predictors of the Late Renal Outcome after Posterior Urethral Valves Ablation in a Developing Country: Long Term Study

Posterior urethral valves are the commonest form of obstructive uropathy in pediatrics and a common cause of chronic kidney disease (CKD) during childhood with estimated renal failure rate of 25-40%. This study aims at evaluating long term changes in kidney and bladder functions of children with posterior urethral valves after ablation, and at assessing predictors of late renal outcome, considering challenges in Egypt as a developing country.

A retrospective study of 30 surgically managed PUVs patients who attended at Alexandria University Children’s Hospital for follow up. Patients underwent surgery between 2005 and 2016. Mean postoperative follow up period was 6.7±3.8 years (range 3.1 to 14.6 years). Data collected included age at presentation, clinical presentation, serum creatinine (initial, nadir, and last follow up), eGFR at last follow up, renal ultrasound (initial, and last follow up), voiding cystourethrogram (initial, and last follow up), and urodynamic studies at last follow up.

Thirty patients underwent PUVs ablation at a median age of 9 months. Ten (33.3%) patients were diagnosed antenatally. At the last follow up visit, 14 (46.7%) patients had moderate-severe CKD. Twenty-five (83.3%) patients had abnormalities in their urodynamic studies. Univariate analysis showed the need for re-ablation, use of anti-cholinergics, high initial serum creatinine, high nadir creatinine, presence of VUR, history of febrile UTIs and presence of proteinwith low eGFR. Multivariate analysis showed that high nadir creatinine and presence of VUR were independent factors associated with lower e-GFR at last follow-up. Antenatal diagnosis was significantly associated with better e-GFR.

Nadir creatinine and vesicoureteral reflux have high prognostic value for late renal functions, and antenatal diagnosis is associated with better renal functions in patients with posterior urethral valves.Increasing family awareness, antenatal care facilities,and referal to tertiary care centers are priorities for promoting the antenatal diagnosis and management in developing countries.Facilities and training for prenatal intervention should be encourageduria were significantly associated