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Antibiotic prophylaxis and recurrent urinary tract infection in children
Jonathan C Craig1, Judy M Simpson, Gabrielle J Williams
1Screening and Test Evaluation Program and the School of Public Health, University of Sydney, Sydney, NSW, Australia.
Insights
Low-dose trimethoprim-sulfamethoxazole significantly reduced urinary tract infections in children predisposed to the condition. This antibiotic therapy proved effective and consistent across various patient subgroups.
Area of Science:
- Pediatric infectious diseases
- Clinical pharmacology
Background:
- Urinary tract infections (UTIs) are common in children.
- Efficacy of prophylactic antibiotics for preventing recurrent UTIs in children lacks robust evidence.
- This study addresses the need for placebo-controlled trials on antibiotic prophylaxis in pediatric UTIs.
Purpose of the Study:
- To evaluate the efficacy of continuous low-dose oral trimethoprim-sulfamethoxazole in preventing UTIs in children predisposed to infection.
- To provide evidence from a placebo-controlled trial on antibiotic prophylaxis for pediatric UTIs.
Main Methods:
- Randomized, placebo-controlled trial involving children under 18 with prior microbiologically proven UTIs.
- Participants received daily trimethoprim-sulfamethoxazole or placebo for 12 months.
- Primary outcome: microbiologically confirmed symptomatic UTI; intention-to-treat analysis.
Main Results:
- 576 children were randomized; median age 14 months, 64% girls.
- UTI developed in 13% of the antibiotic group vs. 19% of the placebo group (HR 0.61, P=0.02).
- Absolute risk reduction of 6 percentage points, consistent across subgroups.
Conclusions:
- Long-term, low-dose trimethoprim-sulfamethoxazole is associated with a modest but significant reduction in UTIs in predisposed children.
- The prophylactic effect was consistent across different patient subgroups.
- Findings support the use of trimethoprim-sulfamethoxazole for UTI prevention in at-risk children.
Background:
Antibiotics are widely administered to children with the intention of preventing urinary tract infection, but adequately powered, placebo-controlled trials regarding efficacy are lacking. This study from four Australian centers examined whether low-dose, continuous oral antibiotic therapy prevents urinary tract infection in predisposed children.
Methods:
We randomly assigned children under the age of 18 years who had had one or more microbiologically proven urinary tract infections to receive either daily trimethoprim-sulfamethoxazole suspension (as 2 mg of trimethoprim plus 10 mg of sulfamethoxazole per kilogram of body weight) or placebo for 12 months. The primary outcome was microbiologically confirmed symptomatic urinary tract infection. Intention-to-treat analyses were performed with the use of time-to-event data.
Results:
From December 1998 to March 2007, a total of 576 children (of 780 planned) underwent randomization. The median age at entry was 14 months; 64% of the patients were girls, 42% had known vesicoureteral reflux (at least grade III in 53% of these patients), and 71% were enrolled after the first diagnosis of urinary tract infection. During the study, urinary tract infection developed in 36 of 288 patients (13%) in the group receiving trimethoprim-sulfamethoxazole (antibiotic group) and in 55 of 288 patients (19%) in the placebo group (hazard ratio in the antibiotic group, 0.61; 95% confidence interval, 0.40 to 0.93; P = 0.02 by the log-rank test). In the antibiotic group, the reduction in the absolute risk of urinary tract infection (6 percentage points) appeared to be consistent across all subgroups of patients (P > or = 0.20 for all interactions).
Conclusions:
Long-term, low-dose trimethoprim-sulfamethoxazole was associated with a decreased number of urinary tract infections in predisposed children. The treatment effect appeared to be consistent but modest across subgroups. (Australian New Zealand Clinical Trials Registry number, ACTRN12608000470392.)
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