Propagation of blaKPC-2 within two sequence types of Escherichia coli in a tertiary referral hospital of northeast India

Abstract

KPC enzyme encoded by blaKPC gene has become a potential source of carbapenem resistance and a challenge to clinicians' worldwide and has been gradually emerging in India. The study investigated Escherichia coli isolates of clinical origin for the carriage of blaKPC-2 along with their resistance profile, carriers, co-existing resistance determinants and clonal types. E. coli isolates with non-susceptibility to ertapenem were collected and were investigated for the presence of blaKPC-2 and co-existence of other carbapenemases, ESBLs, aminoglycoside modifying enzymes genes, 16S methyltransferase genes, sulphonamides and quinolone resistance using PCR assay. Transformation and conjugation assay were performed to check horizontal transferability. Plasmid incompatibility typing and multilocus sequence typing was also performed. Two E. coli isolates belonging to two sequence types ST9582 and ST6171 were identified with the carriage of blaKPC-2. The isolates were multidrug resistant, however, were found were susceptible to colistin, nitrofurantoin and tigecycline. In addition to blaKPC-2, the isolate co-harboured a number of resistance genes including blaNDM-1, blaCTX-M-15, ant(2″)-Ia, aac(3)-I, aac(3)-IIc, aac(6′)-Ib and sul3. The conjugative Inc FIC plasmid was identified in our study with the carriage of blaKPC-2 gene in this study centre. The carriage of blaKPC-2 gene within conjugatively transferable Inc FIC plasmid warrants close monitoring to control inter and intra species spread.