Characterisation of "ESKAPE" Pathogens with Special Reference to Multidrug Resistance and Biofilm Production in a Nepalese Hospital
Abstract Background: “ESKAPE” is an acronym for group of organisms as Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter calcoaceticus baumannii complex, Pseudomonas aeruginosa and Enterobacter spp. They are associated in causing life threatening infections. Global efforts on controlling multidrug resistant (MDR) organisms have been hampered by their rapid emergence, inadequate tests for rapid detection and their ability to escape the antibacterial drugs. The objective of this study was to determine the prevalence of ESKAPE pathogens with prime focus on biofilm production and antibiotic resistance. Methods: A total of 8756 clinical specimens were processed for the isolation and identification of ESKAPE pathogens following standard microbiological protocol. These isolates were subjected to antibiotic sensitivity test as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Detection of resistance phenotypes, viz., extended-spectrum-beta-lactamase (ESBL), metallo-beta-lactamase (MBL), Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin-resistant enterococci (VRE) was done by disk diffusion method and E- test method as applicable. The VRE isolates were subjected for detection of Van A and Van B genes. All the isolates were processed for biofilm detection by tube adherence method. Results: The percentage distribution of Staphylococcus aureus was 33.5%, followed by Klebsiella pneumoniae 33.0%, Pseudomonas aeruginosa 18.3%, Acinetobacter calcoaceticus baumannii complex 8.7%, Enterococcus faecium 5.6% and Enterobacter aerogenes 0.9%. MRSA was 57.6% and Vancomycin resistance among Enterococcus faecium was 20%. ESBL and MBL producing Klebsiella pneumoniae were 16.1%, and 8.1%, Acb complex 10.3% each and Pseudomonas aeruginosa 10.7% and 8.3% respectively. A total of 42.3% of isolates were biofilm producers. Linezolid was drug of choice for VRE isolates. Piperacillin- tazobactam was found to be effective against Pseudomonas aeruginosa, Klebsiella pneumoniae and Enterobacter aerogenes; Ampicillin-sulbactam was the most effective drug against Acb complex excluding polymyxins. Van A gene was detected in all the VRE isolates. Conclusion: This study estimates the burden of the ESKAPE organisms and their antibiotic resistance pattern in a Nepalese hospital. The increasing percentages of drug resistance among these biofilm-producing pathogens pose great threat in medical setting. Surveillance targeting ESKAPE pathogens should be incorporated in infection control policy in Nepal.