The voiding pattern in infants with dilating reflux


Dr U. Sillén Department of Pediatric Surgery, Sahlgren’s University Hospital/Östra, S-416 85 Göteborg, Sweden.



To determine whether the voiding pattern in infants with dilating vesico-ureteric reflux (VUR) differs from that in healthy infants, thus supporting the existence of bladder dysfunction in infants with VUR.

Patients and methods

Forty-one infants (33 boys and eight girls) with dilating VUR (grades 3–5) were studied using a noninvasive 4-hourly voiding record described previously in studies of the voiding pattern of healthy infants, and the results compared with those obtained from healthy infants of similar age.


The voiding pattern in the boys with VUR was characterized by small frequent voids and interrupted voids in more patients (36%) than in healthy boys (15%). Conversely, the girls with VUR were infrequent voiders of relatively high volumes. Residual urine was significantly increased in both boys and girls, as was bladder capacity, although not significantly.


The free voiding pattern in infants with dilating reflux differs from that seen in healthy infants of comparable age. The characteristics for boys and girls differed but was in accordance with that seen in invasive urodynamic studies, suggesting refluxing infants to have a bladder dysfunction.