Antibiotics Reduce Recurrence in Vesicoureteral Reflux

Prophylactic antibiotics lower the recurrence rate in children with vesicoureteral reflux (VUR) but do not affect the risk of renal scarring, concludes a randomized trial in the New England Journal of Medicine.

The multicenter trial included 607 children with VUR diagnosed after one or two episodes of urinary tract infection with fever. The median age was 12 months; 92 percent of the patients were girls.

One group received prophylactic trimethoprim-sulfamethoxazole, and the other group received placebo. The rates of febrile or symptomatic recurrences were compared at 2 years’ follow-up. Secondary outcomes included renal scarring, treatment failure (recurrence, scarring, or both), and antimicrobial resistance.

Antibiotic prophylaxis reduced the rate of recurrent urinary tract infection: 12.9 percent versus 23.6 percent, relative risk 0.55. The hazard ratio for febrile or symptomatic recurrence was 0.50 in the antibiotic group, and this difference widened over time. The benefit was larger in children whose index infection was febrile and in those with baseline bladder and bowel dysfunction: hazard ratios 0.41 and 0.21, respectively.

The rates of renal scarring were similar between groups: 11.9 percent in those taking trimethoprim-sulfamethoxazole and 10.2 percent in those taking placebo. In 97 children with initial recurrence caused by Escherichia coli, isolates resistant to trimethoprim-sulfamethoxazole were found in 63 percent of the prophylaxis group versus 19 percent of the placebo group.

The new trial shows a significant reduction in recurrence with prophylactic trimethoprim-sulfamethoxazole. However, antibiotic treatment does not reduce the risk of renal scarring, and it increases the emergence of antibiotic-resistant bacteria. The authors discuss the implications for decisions about urinary tract imaging in children with VUR after febrile urinary tract infection [The RIVUR Trial Investigators: Antimicrobial prophylaxis for children with vesicoureteral reflux. N Engl J Med 2014; 370:2367–2376].