Posterior Urethral Valves: Primary Voiding Pressures and Kidney Function in Infants
ABSTRACT We evaluated whether high voiding pressures in patients with posterior urethral valves are associated with reduced kidney function.
A total of 25 children younger than 12 months with posterior urethral valves underwent urodynamic evaluation within 15 days of valve ablation between 1994 and 2007. Six patients underwent primary urodynamics before and 19 after valve ablation. A total of 17 patients underwent repeat studies after 1 month and 1 year. Maximum detrusor pressures during voiding and cystometric bladder capacity were compared with kidney function tests. Maximum detrusor pressures during voiding was compared with a control group and data from other studies of male infants.
At presentation median cystometric bladder capacity was 22 ml (range 5 to 125) and maximum voiding pressure was 112 cm H(2)O (40 to 331). There was no statistical difference in bladder capacity and voiding pressures before and after valve ablation. Also, patients with and without vesicoureteral reflux had similar bladder capacities and voiding pressures. There was no association between primary voiding pressures and serum creatinine levels or kidney split function during the first year of life. Primary voiding pressures were about the same as in a control group and in previous studies of males who were healthy, who had reflux or whose status was post-pyelonephritis. Voiding pressures had decreased and bladder capacity had increased significantly at 1-year followup.
Voiding pressures in infants with posterior urethral valves are as high as but not higher than other male infants. High voiding pressures postnatally are not associated with reduced kidney function.
SourceAvailable from: Geert J.M.G. van der Heijden[Show abstract] [Hide abstract]
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ABSTRACT: Bladder function is often compromised in juvenile patients with posterior urethral valves (PUV). In infancy, such abnormal bladder function is characterized by low compliance or overactivity, but later in life the bladder tends to become oversized and empties poorly. Polyuria, which is often associated with renal failure as well as secondary changes in the bladder neck, also has an effect on bladder function. Perhaps as a consequence of these contributing factors, toilet training is often delayed in children with PUV. Adults who were treated for PUV as a child tend to experience lower urinary tract symptoms at a rate twofold to threefold higher than healthy men. Furthermore, these adult patients with PUV might have risk factors for sexual and fertility dysfunctions later in life, such as cryptorchidism, renal failure and abnormal posterior urethra. However, despite the high incidence of these risk factors, sexual function and fertility seems to be normal in most patients.Nature Reviews Urology 11/2012; DOI:10.1038/nrurol.2012.196 · 4.79 Impact Factor