Towards endemicity: large-scale expansion of the NDM-1-producing Klebsiella pneumoniae ST11 lineage in Poland, 2015-16.

OBJECTIVES: In 2015 and 2016 Poland recorded rapid proliferation of New Delhi MBL (NDM)-producing Enterobacterales, with at least 470 and 1780 cases, respectively. We addressed the roles of the Klebsiella pneumoniae ST11 NDM-1 outbreak genotype, already spreading in 2012-14, and of newly imported organisms in this increase. METHODS: The study included 2136 NDM-positive isolates identified between April 2015 and December 2016, following transfer of patients with K. pneumoniae ST147 NDM-1 from Tunisia to Warsaw in March 2015. The isolates were screened by PCR mapping for variants of blaNDM-carrying Tn125-like elements. Selected isolates were typed by PFGE and MLST. NDM-encoding plasmids were analysed by nuclease S1/hybridization, transfer assays, PCR-based replicon typing and PCR mapping. RESULTS: The organisms were mainly K. pneumoniae containing the Tn125A variant of the ST11 epidemic lineage (n = 2094; ∼98%). Their representatives were of the outbreak pulsotype and ST11, and produced NDM-1, encoded by specific IncFII (pKPX-1/pB-3002cz)-like plasmids. The isolates were recovered in 145 healthcare centres in 13/16 administrative regions, predominantly the Warsaw area. The 'Tunisian' genotype K. pneumoniae ST147 NDM-1 Tn125F comprised 18 isolates (0.8%) from eight institutions. The remaining 24 isolates, mostly K. pneumoniae and Escherichia coli of diverse STs, produced NDM-1 or NDM-5 specified by various Tn125 derivatives and plasmids. CONCLUSIONS: The K. pneumoniae ST11 NDM-1 outbreak has dramatically expanded in Poland since 2012, which may bring about a countrywide endemic situation in the near future. In addition, the so-far limited K. pneumoniae ST147 NDM-1 outbreak plus multiple NDM imports from different countries were observed in 2015-16.

Enterobacteriaceae producing OXA-48-like carbapenemases in Poland, 2013-January 2017.

Objectives: To analyse OXA-48 (OXA-48/181)-type carbapenemase-producing Enterobacteriaceae reported in Poland from 2013 until January 2017. Methods: Bacterial isolates were typed by PFGE and MLST. Genes coding for OXA-48/181 types and other ß-lactamases were amplified and sequenced. Mobile elements with blaOXA-48/181-like genes were PCR mapped. blaOXA-48/181-carrying plasmids were characterized by nuclease S1-hybridization profiling, transfer assays and PCR-based replicon typing, while the chromosomal location of the genes was confirmed by the I-CeuI analysis. Results: Fifty-four isolates from 52 patients in 20 hospitals (14 cities) were included, in 14 cases having probable foreign origins indicated. The organisms were genetically diverse and represented numerous pandemic clones, including Klebsiella pneumoniae ST395 (n = 23), ST11, ST15 and ST101, Escherichia coli ST38, ST410 and ST648, and Enterobacter cloacae complex ST78. These produced OXA-48 (n = 49), OXA-181 (n = 4) or OXA-232 (n = 1). One of five K. pneumoniae ST395 pulsotypes caused a multicentre outbreak with 18 cases, which significantly contributed to the total number of patients. Depending on the variant, the blaOXA-48/181-like genes were parts of the Tn1999-, Tn2013- or Tn2016-like transposons, with blaOXA-48 found in an ISEcp1-associated module (Tn2016-like) for the first time. Three genotypes, including E. coli ST38, had chromosomal blaOXA-48 genes, while others carried transmissible IncL (∼60 kb; blaOXA-48; n = 30), IncM (∼80-95 kb; blaOXA-48; n = 4), IncX3 (∼50 kb; blaOXA-181; n = 4) or non-typeable (∼90-160 kb; blaOXA-48 or blaOXA-232) plasmids. Conclusions: Even though OXA-48/181 producers seem to occur infrequently in Poland, their epidemiology has been marked by various phenomena, namely multiple imports, several limited transmissions plus one larger clonal outbreak, and possible plasmid transfers.

Invasive enterococcal infections in Poland: the current epidemiological situation.

The aim of this study was to investigate human invasive isolates of enterococci, obtained through prospective surveillance in Poland. The consecutive enterococcal isolates were collected in 30 hospitals between May 2010 and June 2011, and studied by species identification, antimicrobial susceptibility testing and, for Enterococcus faecium by detection of markers specific for the hospital meroclone, multilocus VNTR analysis (MLVA) and multilocus sequence typing (MLST). Additionally, the genomic difference regions (GDRs) characteristic for lineage 78 were searched by PCR. Among 259 isolates, a nearly equal number of Enterococcus faecalis (n = 140; 54.1 %) and E. faecium (n = 112; 43.2 %) was found. The observed 14-day mortality rate of infected patients reached 18.1 %. All isolates were susceptible to linezolid and daptomycin. High-level aminoglycoside resistance occurred in over 50 % of isolates. Vancomycin resistance mediated by vanA or vanB was detected in 7.1 % of E. faecium; 71.4 % of isolates were multidrug resistant. E. faecium isolates ubiquitously carried molecular markers of hospital-associated meroclone (IS16, esp(Efm), intA of ICEEfm1) and multilocus sequence typing showed the domination of representatives of lineages 78 and 17/18 (52.7 % and 46.4 %, respectively). Isolates of lineage 78 were significantly enriched in all the GDRs studied. The recent spread of E. faecium from this lineage contributed to the observed increase of E. faecium in enterococcal invasive infections in hospitals in Poland.

NDM-producing Enterobacteriaceae in Poland, 2012-14: inter-regional outbreak of Klebsiella pneumoniae ST11 and sporadic cases.

OBJECTIVES: The objective of this study was to characterize New Delhi metallo-ß-lactamase (NDM)-producing Enterobacteriaceae isolates reported in Poland in 2012-14. METHODS: Representative isolates were typed by PFGE and MLST. NDM and other ß-lactamase genes were amplified and sequenced. Plasmids with blaNDM genes were analysed by nuclease S1 plus hybridization profiling, by transfer assays and by PCR-based replicon typing. The blaNDM genetic context was studied by PCR mapping assays. RESULTS: Of 374 cases of infection/colonization with NDM-positive Enterobacteriaceae identified in 2012-14, 370 cases in 40 hospitals, 10 outpatient clinics and 1 nursing home were associated with a Klebsiella pneumoniae outbreak with epicentres in Poznan and Warsaw. The outbreak strain of K. pneumoniae ST11 was similar to an isolate from the Czech Republic from 2013. Like the Czech strain, many of the isolates had two blaNDM-1-carrying IncFII- and IncR-type plasmids of variable size, sharing a blaNDM-1-containing segment. The early isolates also produced CTX-M-15 co-encoded by the IncR-type plasmids, and differentiated later by extensive plasmid rearrangements. Four other NDM cases were reported in 2013, three being associated with arrivals from Montenegro, India or Afghanistan. The Indian Escherichia coli ST448 NDM-5 isolate revealed similarity to a recent isolate from Spain, including the blaNDM genetic context observed previously in E. coli strains in Poland and France (of Congolese and Indian origins, respectively). The Afghani Proteus mirabilis was the second isolate of this species with a chromosomal blaNDM-1 location. CONCLUSIONS: The largest NDM outbreak in a non-endemic country has been observed, being an alarming phenomenon in resistance epidemiology in Poland.

NDM-1- or OXA-48-producing Enterobacteriaceae colonising Polish tourists following a terrorist attack in Tunis, March 2015.

We describe the introduction of NDM-1-producing Klebsiella pneumoniae ST147 and Escherichia coli ST410, and OXA-48-producing K. pneumoniae ST101 strains to Poland by two patients transported to the country after hospitalisation in Tunisia. The patients had gunshot wounds following the terrorist attack in the Bardo National Museum in Tunis in March 2015. Our report reinforces the need for microbiological screening of patients returning from travel on admission to healthcare institutions, especially following hospitalisation in countries where carbapenemase-producing Enterobacteriaceae are endemic.