Multiregional dissemination of KPC-producing Klebsiella pneumoniae ST258/ST512 genotypes in Poland, 2010-14.

OBJECTIVES

In 2008-09, the KPC carbapenemase epidemiology in Poland was dominated by a Klebsiella pneumoniae ST258 KPC-2 outbreak in Warsaw and its administrative region. The aim of this study was to analyse the situation in 2010-14, with a focus on new outbreaks in other parts of the country.

METHODS

KPCs were detected in all suspected isolates by PCR. The detailed study was performed on 173 isolates from 2010 to 2012, and included PFGE and MLST, PCR identification of K. pneumoniae clonal group CG258 clades and potential specificity markers ( pilv-1 , IS 66 and prp ), PCR mapping of Tn 4401 transposons, and plasmid analysis by nuclease S1 profiling and PCR-based replicon typing.

RESULTS

Six hundred and eight KPC cases were identified in Poland in 2010-14, almost half of which occurred in the Warsaw region, and another half in four other areas. The new outbreaks were caused by four K. pneumoniae CG258 genotypes, different from each other and from the organisms spreading in Warsaw. The new lineages were ST258 or ST512 of clade II, and had specific compositions of potential ST258/ST512 clonal markers. The isolates produced KPC-3 encoded by Tn 4401 a or Tn 4401 b elements on plasmids with single or multiple replicons, including I2, FII K (+/-FIB K ), 'FII Y -like', X3 and R. Of other species, Citrobacter freundii ST17 and Enterobacter cloacae ST254 with KPC-2 were identified in a Warsaw hospital.

CONCLUSIONS

The study showed remarkable changes in the KPC epidemiology in Poland in 2010-14, which, following the localized regional spread in the early phase, has converted into multiregional dissemination.