Antimicrobial prophylaxis using trimethoprim/sulfamethoxazole (TMP/SMZ) has been shown to reduce the risk of recurrent urinary tract infection (UTI) by up to 80% in children with vesicoureteral reflux (VUR). This is the first study to provide conclusive clinical evidence for the effectiveness of TMP/SMZ, which has been used to treat VUR in children and prevent recurring UTIs and kidney damage. The results of the NIH-funded clinical trial were published online in the New England Journal of Medicine.
The Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial of 607 children ages 2–71 months of age with Grade I–IV VUR randomized the patients to receive TMP/SMZ (3mg trimethoprim and 15mg sulfamethoxazole per kg of body weight) or placebo at 19 sites in the U.S. Urine specimens, along with renal scanning, were analyzed at baseline and after 1 and 2 years.
Recurrent infection risk was reduced by 50% in children receiving TMP/SMZ compared to placebo and children with VUR and bladder and bowel dysfunction had an 80% lower risk of recurrent infections. Patients with Grade I or II reflux were less likely to have febrile or symptomatic recurrences compared to those with Grade III or IV at baseline (14.3% vs. 22.9%, P=0.003).
While the study did find TMP/SMZ effective in reducing recurrent infection, there was no impact seen on reduction in kidney scarring which could be due to early treatment and awareness of UTI symptoms by parents. Antimicrobial resistance (stool colonization with resistant E. coli) was more common in the TMP/SMZ group but was not considered significant.
For more information visit NIH.gov.