Antibiotics for the prevention of urinary tract infection in children: a systematic review of randomized controlled trials

Objective: The objective was to evaluate the effectiveness of low-dose, long-term antibiotics for the prevention of symptomatic urinary tract infection (UTI) in children. Design: This was a systematic review of randomized controlled trials with a random effects model meta-analysis. Participants: Five trials involving 463 children were performed. Results: Three trials (n = 392) evaluated the effectiveness of long treatment courses of antibiotics (2 to 6 months) for children with acute UTI to prevent subsequent, off-treatment infection. Only 2 trials (n = 71) evaluated the effectiveness of long-term, low-dose antibiotics to prevent on-treatment UTI. Very few of the children enrolled in the trials were boys, had abnormal renal tracts, or were infants. The trial quality was poor, with a lack of blinding, and unstated UTI definitions were almost universal. Long-term antibiotic administration reduced the risk of UTI with treatment (relative risk 0.31, 95% confidence limits 0.10 to 1.00), but there was significant heterogeneity (Q = 13.45, P <.01), and there was no sustained benefit once antibiotics had ceased (relative risk 0.79, 0.61 to 1.02). Conclusions: Methodologic and applicability problems with published trials mean that there is considerable uncertainty about whether long-term, low-dose antibiotic administration prevents UTI in children. Well-designed, randomized, placebo-controlled trials are still required to evaluate this commonly used intervention.