Urinary tract infection trends in Latin American hospitals: report from the SENTRY antimicrobial surveillance program (1997-2000)

Urinary tract infections (UTI) are one of the most common infectious diseases diagnosed in outpatients as well as in hospitalized patients. The objective of this study was to report the frequency of occurrence and antimicrobial susceptibility of uropathogens collected in Latin America between 1997 to 2000 through the SENTRY Antimicrobial Surveillance Program. Antimicrobial susceptibility testing was performed and results interpreted using reference broth microdilution methods. In the 4 year period, a total of 1961 urine isolates from hospitalized patients were included. The patients' mean age was 51.3 years and most of the infections occurred among women (65.6%). Esherichia coli was the most frequent pathogen isolated followed by Klebsiella spp., Pseudomonas aeruginosa, and Proteus mirabilis. Among the E. coli isolates, piperacillin/tazobactam, aztreonam, extended-spectrum cephalosporins, carbapenems and amikacin constitute reasonable therapeutic options for treatment of serious UTI in Latin America (91.0-100.0% susceptible). High resistance rates to fluoroquinolones (17.5-18.9%) and trimethoprim/sulfamethoxazole (>45.0%) were observed among the E. coli. In contrast, nitrofurantoin displayed susceptibility rate of > 87.0%. Against Klebsiella spp. infections, the only effective therapeutic option would be the carbapenems due to the high number of isolates (>30.0%) producing extended-spectrum beta-lactamases (ESBL). Even the new fluoroquinolones showed limited activity against Klebsiella spp. (72.1-88.6% susceptible) and the P. aeruginosa isolates showed high resistance rates to most antimicrobial agents tested. The results of this survey endorse the importance of Enterobacteriaceae as cause of UTI in Latin America. Our results also demonstrate that the uropathogens isolated in the Latin American medical centers exhibit high resistance to various classes of antimicrobial agents. Carbapenem-resistant P. aeruginosa, ciprofloxacin-resistant E. coli, ESBL-producing K. pneumoniae constitute serious problem in this geographic region.