Abstract
OBJECTIVE: To assess the prevalence of antibiotic resistance in Canadian intensive care units.DESIGN: The antimicrobial profiles of 1939 Gram-negative bacilli isolated in 20 Canadian intensive care units were analyzed using a custom designed MicroScan panel.SETTING: The majority of the hospitals were tertiary care institutions, but some community hospitals were included.PATIENTS: Adult intensive care unit patients were the sources of isolates.MAIN RESULTS: Pseudomonas aeruginosa was the most frequently isolated microorganism overall, with Escherichia coli the most common initial isolate. Comparison of initial and repeat isolates showed that P aeruginosa readily acquired resistance to all antibiotic classes except the aminoglycosides. Enterobacter aerogenes developed resistance to ciprofloxacin and Enterobacter cloacae demonstrated resistance to all beta-lactam antibiotics except for imipenem on repeat isolation. Other Enterobacteriaceae remained susceptible. Historical comparison with data derived four years previously from 15 of the centres showed increased resistance of P aeruginosa and Acinetobacter species to ciprofloxacin while other susceptibility patterns remained stable.CONCLUSIONS: The prevalence of Gram-negative resistance in Canadian hospitals is less than that reported in surveys done in some other countries, and was relatively stable over four years.