Non Invasive Urodynamic Assessment in Children-Are They Reliable? Validation of Non-Invasive Urodynamics in Children with Functional Voiding Disorders.

Objectives To validate the non-invasive tests that can predict the type of bladder dysfunction normally diagnosed by invasive urodynamics. Methods Children below 12 yrs of age were evaluated prospectively. Non-invasive urodynamic evaluation included history, clinical examination, frequency volume charting, ultrasonographic scan, urine analysis and renal function tests. Micturating cystourethrogram was carried out in children with recurrent urinary tract infections. All children underwent invasive urodynamic studies and the significance of association of the parameters of noninvasive assessment with invasive urodynamics was determined. Chi square test using Epi 6 software was used for statistical analysis of data. Results 41 children underwent invasive urodynamic studies. The commonest disorder was detrusor instability in 28 (68.2%). Dysynergic voiding was noted in 8 (19.5%). The study was normal in 5 (12.1%). Nocturnal enuresis with day time symptoms, holding maneuvers, small frequent voiding pattern (p<0.05) and a small capacity bladder with insignificant residue (p=0.0003) predicts detrusor instability. Straining (p= 0.0006), large capacity bladder with significant post void residue in the absence of vesicouretric reflux (p<0.05) predicts dysyneric voiding. On combining the various noninvasive tests and validating them against invasive urodynamics in diagnosing detrusor instability and dysnergic voiding, they have a sensitivity of 88.4% and 87.5%, specificity of 72.7% and 69.2%, positive predictive value of 0.88 and 0.63 and positive likelihood ratio of 3.1 & 2.2 respectively. Conclusions Functional voiding disorders can be diagnosed with reasonable accuracy by minimally invasive methods.

Recurrent urinary tract infection and functional voiding disorders.

This study was carried out to determine the association of recurrent urinary tract infections with functional voiding disorders. Sixty eight children with suspected functional voiding disorders were prospectively evaluated clinically and by non-invasive urodynamics. Invasive urodynamics were carried out when indicated. Group I comprised 34 children with symptoms suggestive of functional voiding disorders and recurrent urinary tract infections (mean age 6.3+/-2 yr) and Group II comprised 34 children with symptoms suggestive of functional voiding disorders without recurrent urinary tract infections (mean age 6.7+/-2 yr). The underlying bladder abnormalities in Groups I and II were detrusor instability in 22 (64.7%) and 30 (88.2%), respectively (P>0.05) and dysynergic voiding in 10 (29.4%), and 1 (2.9%), respectively (P<0.05). Children with recurrent urinary tract infections are more likely to have a dysynergic voiding pattern than children presenting with other symptoms of functional voiding disorders.