Single dose trimethoprim-sulphamethoxazole treatment of symptomatic urinary infection.

Seventy-nine children with symptoms of urinary tract infections were randomly allocated to treatment with a single dose or a 7-day course of trimethoprim-sulphamethoxazole. Of the 42 patients (39 girls, 3 boys) who fulfilled the criteria for the trial, 23 were given a single-dose regimen and 19 of them a 7-day regimen. Both groups of patients had sterile urine cultures 2 days after starting treatment. Eight patients had underlying structural renal abnormalities (n = 3, single-dose regimen; n = 5, 7-day regimen). One patient in the single dose group had a recurrence of infection on day 7. These results show that single dose trimethoprim-sulphamethoxazole is as effective as the conventional 7-day course in children with symptomatic urinary tract infection. Further investigation of the renal tract is necessary regardless of the fact that the infection has been eradicated by single-dose treatment.