• Thirty hospitalized children with Gram-negative bacillary urinary tract infections were treated with oxolinic acid for 14 to 21 days. Fifteen of 17 patients with uncomplicated and 11 of 13 with complicated urinary infections had favorable bacteriologic responses. Resistant organisms developed in four treatment failures. Oxolinic acid urine concentrations were well above the minimal inhibitory concentration for most strains of Escherichia coli, Klebsiella, Enterobacter, Proteus mirabilis, P vulgaris, P morganii, and P rettgeri. Approximately half of these patients experienced mild symptoms possibly related to oxolinic acid therapy; in no instance did they require cessation of therapy.
Our experience indicates that if the urine is not sterile by the end of five days of treatment, bacterial resistance to oxolinic acid is likely to have developed, and therapy with another agent should be considered and antibiotic susceptibility tests repeated.
(Am J Dis Child 131:34-37, 1977)