A carbapenem-resistant Klebsiella pneumoniae epidemic clone in Jerusalem: Sequence type 512 carrying a plasmid encoding aac(6')-Ib

Objectives: We characterized distinctive features of a hypertransmissible carbapenem-resistant Klebsiella pneumoniae (CRKP) clone that emerged at Hadassah Hospital, Ein-Kerem, Jerusalem, Israel, in 2006. Methods: Eleven CRKP isolated at Hadassah Hospital during 2005-09 were examined by antimicrobial susceptibility testing, PFGE and multilocus sequence typing (MLST). Plasmids were analysed by conjugation, restriction mapping, PCR and sequencing. Results: Divergence from the national epidemic sequence type (ST) ST258 to ST512 was observed early on. Carbapenem resistance was conferred by bla _KPC-3 carried on a plasmid apparently closely related to pKpQIL, also from Israel. This clone also carried a 15 kb plasmid, designated pAAC154, that carries a Tn1331 derivative containing the aac(6')-Ib gene. pAAC154 does not carry a bla _KPC gene, but is similar to pS15, a plasmid from New York that carries bla _KPC-2. Conclusions: A single CRKP clone ST512 has spread efficiently in our region. In this clone, aac(6')-Ib, common in CRKP strains, is carried on a different plasmid from bla _KPC-3.