BERKELEY, CA (UroToday.com) - Posterior urethral valves (PUV) are the most common infravesical obstruction in a male child. During childhood, obstructive uropathy is known to be responsible for kidney transplantations in 16% of patients.
Progression to end stage renal disease (ESRD) in childhood, in patients with PUV, is well documented. However, long-term prognosis in adulthood among these patients has not been thoroughly investigated. Introduction of maternal ultrasound (US) screening has been a breakthrough in early diagnosis of PUV. Impact of routine maternal US studies on long-term prognosis, however, has not been ultimately salutary. In this study we evaluated the risk of ESRD and the timing of the progression to ESRD in patients with posterior urethral valves.
The database at our institution was evaluated for all patients with PUV treated between 1953 and 2003. The diagnosis of PUV was based on voiding cystourethrography, and was confirmed by urethral endoscopy or open operation in the earliest cases. A total of 200 patients with PUV were identified. Of these, 95% had upper urinary tract dilatation and 64% had vesicoureteral reflux (VUR) at presentation. Renal outcome could be followed in 193 patients. Follow up data on patients treated with dialysis or kidney transplantation were collected from patient records and the Finnish Kidney Transplantation Registry, and the information on deceased patients was gathered from hospital records and the Finnish Population Register Centre.
The patient median age at follow up was 31 years (range 6 to 69). Of the (193) patients, 44 (23%) progressed to ESRD, one third after the age of 17. None of the patients developed end stage renal disease after the age of 34 years. According to a Kaplan-Meier analysis, the lifetime risk of end stage renal disease was 28.5% (SE 3.8%). In the early series with patients born before 1982, in the pre-sonography era, the risk for ESRD was only 16.8%. In those born later, in the post-sonography era, however, the risk of developing ESRD before the age of 27 years was 36.6%. Apparently the patients with the most severe condition in the early series had died before entering childrens`s hospital. Antenatal diagnosis was somewhat more often associated with poor prognosis than postnatal diagnosis.
About one third of PUV patients progress to ESRD, with age. However, after the mid-thirties the risk diminished in this study. High serum creatinine levels at diagnosis, and especially during the first year after valve resection, were signs for poor renal prognosis. In addition the data indicated that primary serum creatinine values as markers of the renal injury had an impact on the speed of progression to ESRD. Early presentation, pneumothorax perinatally, and bilateral VUR as well as recurrent urinary tract infections, also predicted an increased risk for end stage renal disease at follow up. Neither unilateral VUR nor urinomas had effect on prognosis.
Written by:
Jukka Heikkilä, MD and Seppo Taskinen, MD as part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.
Long-term risk of end stage renal disease in patients with posterior urethral valves - Abstract