부산대학교 도서관

Background:Surveillance of antimicrobial resistance (AMR) is of great importance. Pseudomonas aeruginosaand Acinetobacter baumanniiare important pathogens and emergence of resistance in these have increased the morbidity and mortality rates. This surveillance study was initiated by the Government of India - Indian Council of Medical Research. The aim of this study is to determine the antimicrobial susceptibility profile and to characterise the enzyme mediated antimicrobial resistance such as extended spectrum beta-lactamases (ESBLs) and carbapenemases among multidrug-resistant (MDR) P. aeruginosaand A. baumannii. Materials and Methods:A multi-centric study was conducted from January 2014 to December 2015 with a total number of 240 MDR P. aeruginosaand 312 MDR A. baumanniiisolated from blood, cerebrospinal fluid, respiratory, pus, urine and intra-abdominal infections. Kirby–Bauer disc diffusion was done to determine the antimicrobial susceptibility profile. Further, MDR isolates were characterised by multiplex polymerase chain reaction to determine the resistance genes for ESBLs and carbapenemases. Results:Among the ESBLs, blaVEB(23%), blaTEM(5%) and blaSHV(0.4%) in P. aeruginosaand blaPER(54%), blaTEM(16%) and blaSHV(1%) in A. baumanniiwere the most prevalent. Likewise, blaVIM(37%), blaNDM(14%), blaGES(8%) and blaIMP(2%) in P. aeruginosaand blaOXA-23like (98%), blaOXA-58like (2%), blaNDM(22%) and blaVIM(3%) in A. baumanniiwere found to be the most prevalent carbapenemases. blaOXA-51like gene, intrinsic to A. baumanniiwas present in all the isolates tested. Conclusion:The data shown highlight the wide difference in the molecular mechanisms of AMR profile between P. aeruginosaand A. baumannii. In P. aeruginosa, plasmid-mediated mechanisms are much lesser than the chromosomal mediated mechanisms. In A. baumannii, class D oxacillinases are more common than other mechanisms. Continuous surveillance to monitor the trends in AMR among MDR pathogens is important for implementation of infection control and to guide appropriate empirical antimicrobial therapy.