CHARACTERIZATION OF ENTEROCOCCI ISOLATED FROM HUMAN AND NONHUMAN SOURCES IN BRAZIL

A total of 330 enterococci strains isolated from several human (272 st rains) and animal (27) clinical specimens and environmental sources (3 1) in Brazil were identified to species level. Major human sources inc luded urine (48.5%), blood (15.8%), and wounds (9.5%). Human isolates were identified as Enterococcus faecalis (90.0%), E. faecium (6.9%), E . gallinarum (1.1%), E. durans (0.8%), E. casseliflavus (0.4%), E. raf finosus (0.4%), and E. mundtii (0.4%). Strains isolated from animals w ere composed of E. hirae (40.7%), E. faecalis (33.3%), E. faecium (18. 5%), and E. casseliflavus (7.5%). Among environmental isolates, 42.0% were E. faecalis, 35.4% E. faecium, 13.0% E. hirae, 6.4% E. casselifla vus, and 3.2% E. durans. Antimicrobial susceptibility tests were perfo rmed for 200 strains. Overall, high-level resistance (HLR) to aminogly cosides was found in 66 (33.0%) of the strains tested. HLR to gentamic in was detected in 11.5% of the strains, whereas 19.0% of the strains showed HLA to streptomycin and 26.0% showed HLR to kanamycin. Five (22 .7%) of the E. faecium strains were resistant to ampicillin [minimum i nhibitory concentration (MIC) > 32 mu g/ml]. Vancomycin MIC(50) and MI C(90) were 2 and 4 mu g/ml, respectively; only eight strains (identifi ed as E. casseliflavus or E. gallinarum) had MIC of 8 mu g/ml. No beta -lactamase activity was detected by the nitrocefin test.