Vesico-ureteral reflux studied in women with non-neurogenic DO
medwireNews: Vesico-ureteral reflux (VUR) is present in a small minority of women with idiopathic high-pressure detrusor overactivity (IHPDO), suggests a study that identified this complication in 8% of women.
The study authors hypothesise that most women with IHPDO are protected from VUR through intermittent exposure to high detrusor pressures and the ability to decompress the bladder by urethral relaxation.
They warn however that the women in their study were recently diagnosed with IHPDO and that their findings should not be extrapolated to women with more longstanding detrusor overactivity.
Adam Gafni-Kane (North Shore University Health System, Skokie, Illinois) and Peter Sand (University of Chicago Pritzker School of Medicine, Illinois) reviewed the charts of 65 women diagnosed with IHPDO.
All women were neurologically intact and showed detrusor pressures greater than 40 cm H2O during involuntary bladder contractions. The median detrusor overactivity (DO) pressure on cystometry was 65 cm H2O.
Of 50 women who underwent an X-ray voiding cysto-urethrogram, four (8.0%) had VUR (grade I in three women and grade II in one). None of the women with VUR showed any evidence of upper urinary tract deterioration, note the researchers, and the median DO pressure did not differ between women with and without VUR.
Furthermore, DO volumes and the volume instilled at voiding cysto-urethrography did not differ significantly between women with and without VUR.
“In general, women with IHPDO demonstrated mild-to-moderate bladder outlet obstruction, impaired initial and terminal bladder compliance, and urethral relaxation with both involuntary leakage and voluntary micturition”, the researchers remark in the International Urogynecology Journal. “Many women exhibited dysfunctional voiding; however, the majority of the subjects voided normally.”
The authors contrast the relatively low risk of VUR in this series of patients with the much higher risk among children with neurogenic bladder and suggest that “[k]ey differences to consider between these two populations include those related to timing of exposure to high intravesical pressures, compliance, and outlet resistance.”
They conclude that their results “are generalizable to women with IHPDO who present to tertiary centers for evaluation”, but add: “Given that the effect of prolonged exposure to IHPDO is unknown, the results should not be applied to women with IHPDO who present with symptoms of more than 2 years’ duration.”
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2014
By Joanna Lyford, Senior medwireNews Reporter