Antimicrobial resistance profiles of enterococci isolated from poultry meat and pasteurized milk in Rio de Janeiro, Brazil

ABSTRACT

The enterococci are important nosocomial pathogens with a remarkable capacity of expressing resistance to several antimicrobial agents. Their ubiquitous nature and resistance to adverse environmental conditions take account for their ability to colonize different habitats and for their potential for easy spreading through the food chain. In the present study we evaluated the distribution of species and antimicrobial susceptibility among enterococcal isolates recovered from food obtained in retail stores in Rio de Janeiro, Brazil. The following species were identified among 167 isolates obtained from poultry meat and 127 from pasteurized milk Enterococcus faecalis (62.6 percent), E. casseliflavus (17.3 percent), E. durans (6.5 percent), E. gallinarum (3.0 percent), E. gilvus (2.4 percent), E. faecium (2.0 percent), E. hirae (1.4 percent), and E. sulfureus (1.0 percent). The overall percentages of antimicrobial resistant isolates were 31.2 percent to tetracycline, 23.8 percent to erythromycin, 11.3 percent to streptomycin, 4.3 percent to chloramphenicol, 3.9 percent to gentamicin, 1.4 percent to norfloxacin, 1.1 percent to imipenem, 0.7 percent to ciprofloxacin, nitrofurantoin, and penicillin, and 0.4 percent to ampicillin. Intermediate resistance was detected in frequencies varying from 0.5 percent for linezolid to 58.2 percent for erythromycin. None of the isolates showed resistance to glycopeptides. High-level resistance to aminoglycosides was observed in 13.1 percent of the isolates. Multiresistance was observed in E. faecalis, E. casseliflavus, E. faecium, E. gallinarum, E. durans and E. gilvus.