Study: Does antibiotic prophylaxis prevent pyelonephritis in children with vesicoureteral reflux?

August 1, 2008

Continuous antibiotic prophylaxis in children with vesicoureteral reflux may be ineffective.

A new study indicates that continuous antibiotic prophylaxis in children with vesicoureteral reflux (VUR) not only is ineffective in preventing recurrent acute pyelonephritis, but also does not prevent the appearance of new kidney scars.

The Italian study examined 100 children younger than 30 months who had VUR grade II, III, or IV, either unilateral or bilateral. The 50 children assigned to the intervention group received antibiotic prophylaxis with sulfamethoxazole/trimethoprim (SMX/TMP), whereas the 50 children in the control group did not. After two years, children in the intervention group stopped taking antibiotics even when VUR persisted. Patients in both groups were followed up for an additional two years-a total of 4 years-and underwent cystourethrography, renal ultrasound, and dimercaptosuccinic acid renal scans.

In the first two years of follow-up, 33 children (33%) had at least one pyelonephritis recurrence-18 (36%) in the intervention group and 15 (30%) in the control group. The total number of recurrences in the two groups were 42 and 35, respectively. In the subsequent two years, when prophylaxis was discontinued in the intervention group, only three patients developed pyelonephritis: one in the intervention group and two in the control group. None of the differences between the groups was statistically significant.

Commentary

Piece by piece, everything we "knew" about urinary tract infection (UTI) associated with reflux is changing. This study supports a 2007 retrospective study from the Children's Hospital of Philadelphia, which found that prophylaxis was ineffective in preventing recurrence of UTI and was associated with increased antibiotic resistance (Conway P et al: JAMA 2007;298:179). Meanwhile, other studies question the usefulness of both renal ultrasound and voiding cystourethrography after UTI. For a concise summary of how our understanding of UTI is shifting, see DeMuri GP et al: Pediatr Infect Dis J 2008;27:553.

DR. BURKE, section editor for Journal Club, is chairman of the department of pediatrics at Saint Agnes Hospital, Baltimore. He is a contributing editor for Contemporary Pediatrics. He has nothing to disclose in regard to affiliations with, or financial interests in, any organization that may have an interest in any part of this article.