Long-term antibiotics for preventing recurrent urinary tract infection in children.

BACKGROUND: Urinary tract infection (UTI) is common in children. Symptoms include fever, lethargy, anorexia, and vomiting. UTI is caused by Escherichia coli in over 80% of cases and treatment is a course of antibiotics. Due to acute illness caused by UTI and the risk of pyelonephritis-induced permanent kidney damage, many children are given long-term antibiotics aimed at preventing recurrence.

OBJECTIVES: To determine the efficacy and harms of long-term antibiotics to prevent recurrent UTI in children.

SEARCH STRATEGY: In November 2010 we searched without language restriction MEDLINE, EMBASE, CENTRAL (in the Cochrane Library), the Cochrane Renal Group's Specialised Register, reference lists of review articles and contacted content experts.

SELECTION CRITERIA: Randomised comparisons of antibiotics with other antibiotics, placebo or no treatment to prevent recurrent UTI.

DATA COLLECTION AND ANALYSIS: Two authors independently assessed and extracted information. A random-effects model was used to estimate risk ratio (RR) and risk difference (RD) for recurrent UTI with 95% confidence intervals (CI).

MAIN RESULTS: Twelve studies (1557 children) were identified with six (five analysed, 1069 children) comparing antibiotics with placebo/no treatment. Duration of antibiotic prophylaxis varied from 10 weeks to 12 months. Compared to placebo/no treatment, when all studies were included, antibiotics did not appear to reduce the risk of symptomatic UTI (RR 0.75, 95% CI 0.36 to 1.53) however when we evaluated the effects of antibiotics in studies with low risk of bias, there was a statistically significant reduction (RR 0.68, 95% CI 0.48 to 0.95). The effect was similar in children with vesicoureteric reflux (VUR) (RR 0.65, 95% CI 0.39 to 1.07) compared to those without VUR (RR 0.56, 95% CI 0.15 to 2.12). There was no consistency in occurrence of adverse events. Three studies reported antibiotic resistance, showing a non-significant increased risk for resistance to the antibiotic in the active treatment groups (RR 2.4, 95% CI 0.62 to 9.26).Five studies (4 analysed, 367 children) compared one antibiotic with another but all compared different combinations or different outcomes and studies were not pooled. Two studies reported microbial resistance, nitrofurantoin having a significantly lower risk of resistance than cotrimoxazole (RR 0.54, 95% CI 0.31 to 0.92).One study compared alternate with every day cefadroxil treatment.

AUTHORS' CONCLUSIONS: Long-term antibiotics appear to reduce the risk of repeat symptomatic UTI in susceptible children but the benefit is small and must be considered together with the increased risk of microbial resistance.