An update of the evolving epidemic of blaKPC-2-carrying Klebsiella pneumoniae in Greece (2009-10)

Abstract

Objectives: To follow the epidemic of KPC-2-producing Klebsiella pneumoniae in Greece. Methods: KPC-2-producing isolates (n = 378) were collected during January 2009-April 2010 in 40 Greek hospitals. blaKPC and blaVIM were detected by PCR. Carbapenemase production was confirmed by spectrophotometry. Sequences flanking blaKPC-2 and their plasmid carriers were studied. Isolates were typed by PFGE and multilocus sequence typing (MLST). Results: All 378 isolates were blaKPC-2 positive; 18 also carried blaVIM-1/VIM-4. Higher isolation frequencies were observed in Athens and Crete. Isolates were classified into 13 PFGE types and 11 sequence types (STs). ST258 was predominant (n = 322), followed by ST147 (n = 20), ST383 (n = 9), ST133 (n = 6), ST274 (n = 4) and ST323 (n = 3). Of the remaining isolates, seven were distributed into five STs (11, 17, 340 and the novel 494 and 495) and seven were not typed. blaKPC-2 could not be transferred from ST258 isolates, in contrast to isolates of ST17, ST133, ST147, ST274, ST494 and ST495. All blaKPC-2-encoding plasmids were of similar size (~100 kb) and showed indistinguishable restriction fragment length polymorphism (RFLP) patterns except those from the ST340 isolates. Sequences flanking blaKPC-2 revealed that the Tn4401a isoform was present in plasmids from all STs except ST340 containing Tn4401b. Co-production of VIM enzymes was observed in isolates of ST147, ST323 and ST383. Conclusions: Apart from the epidemic of KPC-2-producing K. pneumoniae belonging to ST258 in Greece, diffusion of blaKPC-2 to at least 10 additional STs has taken place. Notably, strains from three of the latter STs (147, 323 and 383) were found to carry both blaKPC-2 and blaVIM. © The Author 2011. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.