Antimicrobial susceptibility of bacteria causing urinary tract infections in Latin American hospitals: results from the SENTRY Antimicrobial Surveillance Program (1997).

OBJECTIVE

To evaluate the antimicrobial susceptibility patterns among 469 pathogens isolated as a significant cause of urinary tract infections in 10 Latin American medical centers.

METHODS

Consecutively collected isolates were susceptibility tested by broth microdilution methods, and selected isolates were characterized by molecular typing methods.

RESULTS

Escherichia coli and Klebsiella spp. isolates revealed high rates of resistance to broad-spectrum penicillins and to fluoroquinolones. Ceftazidime MICs of >/=2 mg/L, suggesting the production of extended-spectrum b-lactamases (ESBLs), were observed in 37.7% of K. pneumoniae and 8.3% of Escherichia coli isolates. Enterobacter spp. isolates were characterized by high resistance rates to ciprofloxacin (35%) and to ceftazidime (45%), but they generally remained susceptible to cefepime (95% susceptible). Pseudomonas aeruginosa and Acinetobacter spp. were highly resistant to ciprofloxacin and ceftazidime. Imipenem was active against 80% of P. aeruginosa and 93% of Acinetobacter spp. isolates.

CONCLUSIONS

Our results demonstrate a high level of resistance to various classes of antimicrobial agents among isolates causing nosocomial urinary tract infections in Latin American hospitals. Clonal dissemination of ESBL-producing K. pneumoniae strains was infrequent.