First evidence of KPC-producing ST258 Klebsiella pneumoniae in river water.

This paper reports the first case of Klebsiella pneumoniae carbapenemase (KPC)-2-producing K. pneumoniae in river water in Croatia. In total, four KPC-2-producing K. pneumoniae isolates were analysed. All isolates shared a similar genetic background, belonging to ST258. Isolates displayed uniform, multi-drug-resistant profiles susceptible to colistin. blaSHV-1, aac(3')-II, aac(6')-Ib and aph(3')-Ia genes were detected in all isolates. In all isolates, the blaKPC-2 gene was localized on a single non-conjugative IncFII plasmid that varied in size (∼140, ∼230, ∼225 and ∼220 kb). K. pneumoniae was viable in river water for up to 50 days, confirming its ability to survive and disseminate in the environment.