Urodynamic evaluation in primary enuresis: an investigative and treatment outcome correlation

A prospective study was done in pediatric out-patient department of a tertiary care hospital to evaluate the role of urodynamics in the management of primary enuresis in the 5-14-year-old children and to compare the effectiveness of multidimensional behavioral therapy with pharmacological therapy. Hundred and nineteen children between 5-14 years with primary enuresis were evaluated clinically and investigated. Three patients with obvious organic causes were then excluded. The remaining patients were given either behavioral or pharmacological treatment on the basis of urodynamic assessment. Urodynamic abnormalities were seen in 80/116 (68.9%) patients namely uninhibited bladder contraction 50/116 (43.1%), small bladder capacity 20/116 (17.2%), large bladder capacity 4/116 (3.4%), decreased bladder compliance 3/116 (2.5%) and detrusor sphincter dyssenergia 3/116 (2.5%). Combination of abnormal micturition history stating daytime urgency or frequency or dysfunctional voiding symptoms like squatting and/or abnormal voiding charts could predict abnormal results of urodynamics correctly with sensitivity of 81% and specificity of 86.2%. Ultrasound identified only 38/80 enuretics with urodynamic abnormalities although it was 100% specific. Additionally one patient who was identified as having a small bladder capacity on voiding chart was seen to have mild pelvicalyceal dilatation on ultrasound and subsequently on urodynamic assessment was found to have Detrusor sphincter dyssenergia (DSD). Behavioral therapy as compared to drug therapy produced more complete remission (17/18 vs. 14/18) and lesser relapse rate (2/17 vs. 5/14) in monosymptomatic enuretics with normal urodynamics. In patients with urodynamic abnormality, response rates with behavioral therapy, imipramine, oxybutynin and flavoxate were 73.9% (CI 56-91.8%), 89.4% (CI 75.7-100%), 94.2% (CI 84.7-100%) and 89.4% (CI 75.7-100%), respectively. Specific drug therapy as per the urodynamic abnormality was significantly more effective 49/57 [86% (CI 77-95%)] vs 17/23 [73.9% (CI 56.1-91.9%)] at P < 0.05 than behavioral therapy in patients with underlying abnormal urodynamics. Micturition history and voiding chart can be used as screening tool for enuretics. Behavioral therapy should be the first line treatment for mono symptomatic and drug therapy for polysymptomatic enuretics. Urodynamic testing may be reserved for polysymptomatic enuretics with abnormal ultrasound or those who fail to respond to first line treatment.