Objectives: To assess the epidemiological features of 76 KPC producing K. pneumoniae isolates (KPC-Kp) recovered in 3 hospitals of Buenos Aires, Argentina, during 2015-2017. Methods: Antimicrobial susceptibilities were determined according to CLSI. Molecular typing of KPC-Kp was performed by PFGE-XbaI and MLST. Plasmid encoded genes involved in carbapenem, fosfomycin and colistin resistance were detected by PCR and sequencing. Also mgrB inactivation was investigated in those colistin resistance isolates. Genetic platforms involved in horizontal spread of bla KPC were investigated by PCR mapping.Results: Besides β-lactams, high resistance rates were observed for gentamycin, quinolones and trimethoprim-sulfamethoxazole. KPC-Kp ST258 corresponded to

The efflux mechanism seems to be an important mechanism to confer resistance to antibiotics and biocides through MDR pumps. It was observed that several qac genes coexist in some of the isolates and seem to act simultaneously in the removal of different compounds out of the bacterial cell. The qac genes are horizontally spread among different clones.