An approach to evaluating antibacterial agents in the treatment of urinary tract infection.

The evaluation of antibacterial therapy for urinary tract infection (UTI) is based on the results of randomized, controlled comparative studies (preferably double-blinded) in which sufficient numbers of patients are entered into both arms to ensure statistical validity. Since the term UTI encompasses a broad array of clinical syndromes (acute uncomplicated UTI; acute uncomplicated pyelonephritis; complicated UTI; and asymptomatic bacteriuria), the design of clinical studies should include a careful definition of the clinical syndromes being studied, the course of therapy prescribed, and the microbiological characterization necessary for evaluability. End points to be considered in the evaluation of new therapies include the effect of therapy on clinical symptoms; the ability of the therapy to eradicate the original infecting organism; the incidence of reinfection posttherapy; the number of instances of primary drug resistance of the infecting inoculum; and the incidence of adverse effects with a particular regimen.