Prevalence of High Level Aminoglycoside Resistance and Vancomycin Resistance in Enterococcal Isolates at A Tertiary Care Hospital

Background and Aim: Vancomycin resistant Enterococci (VRE) and high level aminoglycoside resistant (HLAR) Enterococci have complicated the available treatment modalities for Enterococci worldwide. The existing study was planned to evaluate the occurrence of HLAR and VRE strains in a tertiary care center in India and to study the association of HLAR with vancomycin sensitive Enterococci (VSE) and VRE. Materials and Methods: A total of 50 enterococcal isolates from various clinical specimens were incorporated in the study. Speciation was done on the basis of standard biochemical tests. HLAR was tested by the disc diffusion method using 150µg gentamicin disc and 200 µg streptomycin discs. Vancomycin susceptibility patterns were reported using vancomycin disc and agar dilution methods. Results & Conclusion: Pus samples comprised of the majority for the isolation of enterococcal strains (40%). 54% isolated strains were HLGR, 32% were HLSR and 14% isolates were positive for both HLGR and HLSR. 61.7% of Enterococcus faecium isolates demonstrated resistance for high-level gentamicin (HLGR) and 43.75% Enterococcus faecalis isolates were resistant to high-level streptomycin (HLSR). When VRE was compared to VSE, the rate of HLSR was detected to be 4.64% in VRE, while it was 32.55% in VSE; the rate of HLGR was noted to be 11.62% in VRE and it was 41.87% in VSE. The association of HLGR with HLSR (HLAR) was 2.32% in VRE and 13.95% in VSE strains. Enterococci strains are showing an increase in their antimicrobial resistance patterns. The increment of such strains in health care settings has to be reserved and controlled to avert complicated infections.