Epidemiology and vancomycin susceptibility pattern of methicillin resistant coagulase negative Staphylococcal (CoNS) isolates from skin swabs of the surgical patients in the National Hospital of Sri Lanka

Background: Coagulase-negative staphylococci (CoNS) are commonly found in human skin as normal flora but are increasingly prevalent in hospital-acquired infec-tions, often exhibiting resistance to methicillin (MRCoNS). Vancomycin is the primary treatment for MRCoNS infections. This study aimed to assess MRCoNS pre-valence in a hospital community and evaluate Vancomycin effectiveness against MRCoNS.Methods: Swabs from 102 hospitalized surgical patients were tested before the surgery for CoNS presence. Methicillin resistance was confirmed using cefoxitin discs. Vancomycin Minimum Inhibitory Concentrations (MICs) were determined via broth microdilution and E-test.Results: Among 60 CoNS-positive patients, 42% carried MRCoNS. All MRCoNS isolates exhibited MICs within a susceptible range (0.5-2 μg/ml). There was a significant prevalence of MRCoNS (42%) among hospitalized patients. Vancomycin demonstrated consistent efficacy against MRCoNS strains, with MICs well below the clinical breakpoint of 4 μg/ml in both testing methods.Conclusion: Despite the high occurrence of methicillin resistance in the studied community, Vancomycin remains a reliable treatment option, reinforcing its pivotal role in combating infections caused by MRCoNS.