[A study on the treatment duration of an antibacterial agent in complicated urinary tract infections. Utility and recurrence after 14-day treatment by fleroxacin].

In this study, fleroxacin (FLRX), a new quinolone derivative, was orally given at 300 mg once daily for 14 days to 102 patients with non-catheterized complicated urinary tract infections in order to determine the optimal treatment duration. We investigated its efficacy at day 5-7 and day 14, according to the criteria proposed by the Japanese UTI Committee, and also to the recurrence rate after the withdrawal. The results were as follows: 1. Overall clinical efficacy rates were 86% at day 5-7 and 84% at day 14. Both incidence of bacterial replacement in bacteriuria and normalization in pyuria were increased at day 14 as compared with those at day 5-7. 2. Bacteriological eradication rates were 91% at day 5-7 and 89% at day 14. 3. Clinical efficacy rates from physicians' evaluation were 86% at day 5-7 and 88% at day 14. 4. Incidence of side effects was 9.1%, and most of the cases were gastrointestinal symptoms which appeared within 4 days. Slight and transitory changes in laboratory findings were noted in 2.3% of evaluable cases. 5. With the occurrence of pyuria and bacteriuria as markers, the "no recurrence" rates were 63% at 1 week, 54% at 2 weeks, 61% at 3 weeks, 81% at 4-6 weeks after the withdrawal, and the "recurrence" rates were 4%, 4%, 6% and 5%, respectively. Remaining cases were judged as "reserved assessment". Generally, aggravation of bacteriuria was found but the aggravation of pyuria was observed in only few cases. 6. According to breakdown of cases with bacteriuria only, cure rate was 67% and recurrence rate was 33%. Re-infections were observed much more frequently than relapse based on the identification of infecting organisms. These results suggest that sufficient bacteriological eradication and clinical efficacy could be obtained by 14-day treatment of FLRX in non-catheterized complicated urinary tract infections. The efficacy of the treatment became evident around day 7. In approximately 30% of the cases in which eradication of the initial causative organisms was observed at day 14 reappearance of bacteriuria (greater than or equal to 10(3) CFU/ml) occurred after withdrawal of the antibiotic, but cases with pyuria were few, and the incidence of true recurrence was generally low. Onset of side effect after 5-day was not seen, hence FLRX seemed to be a safe agent.