Evaluation of the Bladder Stimulation Technique to Collect Midstream Urine in Infants in a Pediatric Emergency Department

OBJECTIVE Midstream clean-catch urine is an accepted method to diagnose urinary tract infection but is impracticable in infants before potty training. We tested the bladder stimulation technique to obtain a clean-catch urine sample in infants. MATERIALS AND METHODS We included 142 infants under walking age who required a urine sample in a cross-sectional study carried out during a 3-months period, from September to November 2014, in the emergency department of the University Children's Hospital of Nice (France). A technique based on bladder stimulation and lumbar stimulation maneuvers, with at least two attempts, was tested by four trained physicians. The success rate and time to obtain urine sample within 3 minutes were evaluated. Discomfort (EVENDOL score ≥4/15) was measured. We estimated the risk factors in the failure of the technique. Chi-square test or Fisher's exact test were used to compare frequencies. T-test and Wilcoxon test were used to compare quantitative data according to the normality of the distribution. Risk factors for failure of the technique were evaluated using a multivariate logistic regression model. RESULTS We obtained midstream clean-catch urine in 55.6% of infants with a median time of 52.0 s (10.0; 110.0). The success rate decreased with age from 88.9% (newborn) to 28.6% (>1 y) (p = 0.0001) and with weight, from 85.7% (<4 kg) to 28.6% (>10 kg) (p = 0.0004). The success rate was 60.8% for infants without discomfort (p<0.0001). Heavy weight and discomfort were associated with failure, with adjusted ORs of 1.47 [1.04-2.31] and 6.65 [2.85-15.54], respectively. CONCLUSION Bladder stimulation seems to be efficient in obtaining midstream urine with a moderate success rate in our study sample. This could be an alternative technique for infants before potty training but further randomized multicenter studies are needed to validate this procedure.