Trimethoprim in the treatment of acute urinary tract infections in children.

In the first study to assess the effect of trimethoprim in the treatment of acute urinary tract infections in children, we compared it with sulphisoxazole. Eighteen girls, mean age 5.3 years, were treated with trimethoprim 6 mg/kg/day. Seventeen girls, mean age 5.0 years, treated with sulphisoxazole 150-200 mg/kg/day for 10 days served as controls. All infections were cured. Three patients in each group had reinfections during the 6 months of follow-up. In each group, one of the reinfections occurred within 2 weeks after the end of the treatment. One patient developed a rash from sulphisoxazole and so required drug change. No other adverse effects were observed. We conclude that trimethoprim is as effective as sulphisoxazole in the treatment of simple acute urinary tract infections of children and recommend it, in the dosage used, as an alternative first-choice drug, especially for patients who have had side effects from sulphonamides or nitrofurantoin.