Risk factors for progression to end-stage renal disease in children with posterior urethral valves

UROLOGICAL SURVEY

PEDIATRIC UROLOGY

Risk factors for progression to end-stage renal disease in children with posterior urethral valves

Ansari MS; Gulia A; Srivastava A; Kapoor R

Department of Urology and Renal Transplantation, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India

J Pediatr Urol. 2010; 6: 261-4

OBJECTIVE: To identify the variables which affect long-term renal outcome in children with posterior urethral valves (PUV).

MATERIALS AND METHODS: Retrospective analysis of 260 children with PUV who underwent ablation of valves in 1992-2008 at our tertiary care center. The following risk factors for progression to end-stage renal disease (ESRD) were analyzed: nadir serum creatinine greater than 1.0mg/dL, bilateral grade 3 or higher VUR at diagnosis, recurrent febrile UTIs, and severe bladder dysfunction. Patients were divided into two groups: those who developed ESRD (group 1) and those who did not (group 2).

RESULTS: Forty (17.62%) patients had nadir serum creatinine > 1mg/dL. At time of initial presentation, high-grade VUR was seen in 63.1% and 33.5% of groups 1 and 2, respectively (P = 0.002). Overall, 77 (34%) of the boys developed breakthrough urinary tract infections: 37.03% and 33.5% in groups 1 and 2, respectively (P = 1). Fifty-nine (26%) patients were found to have severe bladder dysfunction: 77.8% and 19% in groups 1 and 2, respectively (P < 0.0001). Twenty-seven (11.89%) patients progressed to ESRD, at mean age of 11.21 years (5-16). On univariate analysis, the risk-predicting variables were: nadir serum creatinine value greater than 1mg/dL (P < 0.0001), bilateral high-grade VUR (P = 0.002) and severe bladder dysfunction (P < 0.0001). On multivariate logistic regression analysis, nadir serum creatinine greater than 1mg/dL (OR 23.79; CI 8.20-69.05) and severe bladder dysfunction (OR 5.67; CI 1.90-16.93) were found to be independent risk factors predictive of ultimate progression to ESRD.

CONCLUSIONS: Nadir serum creatinine and bladder dysfunction are the main factors affecting long-term renal outcome in cases of PUV. Early identification and treatment of bladder dysfunction may thus be beneficial.

Editorial Comment

This paper looked at a large series of children with posterior urethral valves in order to identify risk factors for end-stage renal disease. Patients were followed for a mean of 7.2 years. A total of 227 patients were eligible for inclusion in the review. The authors looked at age at presentation, nadir serum creatinine, presence of high-grade reflux, recurrent febrile urinary tract infections, and severe bladder dysfunction as variables. 30% of patients developed chronic kidney disease and 12% progressed to end-stage renal disease. On univariate analysis nadir creatinine greater than 1 mg/dL, bilateral high-grade reflux, and severe bladder dysfunction were found to be risk factors. On multivariate analysis; however, only nadir serum creatinine greater than 1 mg/dL and severe bladder dysfunction were predictive of progression to end-stage renal disease.

The strength of this study is the large number of patients at a single institution. Certainly longer follow-up would likely reveal a greater number of patients who progress to end-stage renal disease. Their findings are in line with another large series recently published which also demonstrated bladder dysfunction and nadir creatinine to be the only independent risk factors for end-stage renal disease using multivariate analysis (1). While nadir serum creatinine is not a modifiable risk factor, bladder dysfunction can certainly be managed aggressively in these at risk patients. This paper helps to reemphasize the importance of screening for bladder dysfunction early on. It remains to be seen whether or not early and aggressive management of bladder dysfunction can have an impact on outcomes.

Dr. M. Chad Wallis

Division of Pediatric Urology

University of Utah

Salt Lake City, Utah, USA

E-mail: [e-mail]

• 1. DeFoor W, Clark C, Jackson E, Reddy P, Minevich E, Sheldon C: Risk factors for end stage renal disease in children with posterior urethral valves. J Urol. 2008; 180 (4 Suppl): 1705-8; discussion 1708.

Publication Dates

• Publication in this collection
  30 May 2011
• Date of issue
  Apr 2011