Single dose antibiotic therapy is not as effective as conventional regimens for management of acute urinary tract infections in children.

One hundred thirty-two children with acute urinary tract infection were randomly assigned to receive trimethoprim-sulfamethoxazole in one dose, two doses daily for 3 days or two doses daily for 7 days. The patient characteristics, etiologic agents and frequency of roentgenologic abnormalities were similar for the three treatment groups. There was no significant difference in bacteriologic cure rates for the single dose regimen (93%) and multidose regimens (96%). The difference in rates of recurrent urinary tract infection between the single dose (20.5%) and 3-day (5.6%) and 7-day (8%) regimens was statistically significant (P = 0.033). A single dose of trimethoprim-sulfamethoxazole is inadequate treatment for infants and children with acute urinary tract infection.