Antibiotic prophylaxis in preventing urinary tract infection in children with low grade vesicoureteral reflux: results from a prospective randomized study

Purpose Antibiotic prophylaxis is administered to children at risk of a urinary tract infection (UTI). However proof of its effectiveness in children with low grade vesicoureteral reflux (VUR) is lacking. Our objective was to determine whether antibiotic prophylaxis reduced the incidence of a UTI . Material and methods Children, 1-month to 3-years-old, with low grade VUR, were assigned randomly to receive daily cotrimoxazole or not and then followed up for 18 months. Clinical examination and renal ultrasound were carried out at 9 and 18 months, and a voiding cystourethrogram at 18 months. A UTI constituted an exit criteria. Survival curves without infection were compared with a log-rank test. Results 223 children were enrolled, 102 in the cotrimoxazole group and 121 in the control group. Sex, age at inclusion and grade of reflux were similar in the two groups. There was no significant difference for the occurrence of UTI or pyelonephritis between the two groups. Considering pyelonephritis, there was no significant difference for girls, whatever the grade of VUR. However, prophylaxis tended to reduce pyelonephritis only for boys with grade III VUR. Conclusions These data suggested that antibiotic prophylaxis did not reduce the incidence of UTI in young children with low grade VUR. However, it may prevent further pyelonephritis in boys with grade III VUR.