Abstract
Introduction: Enterococci have rapidly emerged as important nosocomial and community acquired pathogens. Enterococcus. faecalis has accounted for approximately 80-90% of the isolates causing human infection.
Aim & Objectives: To identify the etiology of wound infection and to determine the antibiotic resistance pattern of Enterococci isolates.
Materials & Methods: A total 61 bacterial isolates obtained from wound swabs over a period of six months were included in this study. Enterococci isolates were identified by colony morphology, gram staining, catalase test, growth in the presence 6.5% sodium chloride, aesculin hydrolysis in the presence of 40% bile and by biochemical reactions using Facklam and Collins scheme. Antimicrobial susceptibility testing was done according to the CLSI guidelines by the disc diffusion method of Kirby-Bauer. Vancomycin resistance and High level aminoglycoside resistance were tested by the disc diffusion method and the agar screen method and Minimum Inhibitory Concentration testing was done by the E test.
Results: The prevalence of Enterococcus. faecalis isolates from wound infection was found to be 16.39 %. By E test 3 Enterococcus. faecalis isolates were resistant to High level Gentamicin (≥512µg/ml), Minimum Inhibitory Concentration (MIC) of Teicoplanin was found in the range of 0.5-4 µg/ml and for vancomycin, MIC was in the range of 0.5-2 µg/ml. One isolate was found to be resistant to Linezolid with MIC of ≥8µg/ml.
Conclusion: Rapid and accurate susceptibility testing results, effective therapy and infection control measures are necessary to prevent the spread of multidrug resistant enterococci.
Keywords: Nosocomial infection, Multi Drug Resistant Enterococci, Minimum Inhibitory Concentration, Agar screen method, E test.
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Corresponding Author
Reena Rajan
Senior Lecturer, Department of Microbiology, Penang International Dental College,
Vinayaka Mission 's Research Foundation (Deemed to be University), Salem, Tamil Nadu
DOI: https://dx.doi.org/10.18535/jmscr/v6i6.164
