Resistance to antibiotics in clinical isolates of the genus Enterococcus

Abstract

The purpose of our study was to determine the prevalence of resistance in 114 clinical strains of enterococci. Identification was made using PASCO dehydrated panels and by the conventional method of Facklam and found the following: 92.1% E. faecalis, 7% E. faecium and 0.9% E. avium. The antibiotic susceptibility was determined by the PASCO system, and the minimum inhibitory concentrations of vancomycin, teicoplanin, gentamicin and streptomycin were determined by the agar dilution method. All the strains were susceptible to vancomycin and teicoplanin. We detected resistance to ampicillin in 4.4% of isolates, to penicillin in 6%, to tetracycline in 41.2%, to rifampicin in 12.3%, to chloramphenicol in 23.7%, to erythromycin in 66.7%, to ciprofloxacin in 53.5%, to gentamicin to a high level in 43.9%, and to streptomycin to a high level in 57%. E. faecium was associated with high-level resistance to gentamicin. E. faecium was more resistant than E. faecalis to quinolones, rifampicin, penicillin and ampicllin, and showed similar susceptibility to tetracycline and chloramphenicol. However, E. faecalis was more resistant than E. faecium to aminoglycosides, mainly to gentamicin.