Pol J Microbiol. 2021 Mar;70(1):107-116. doi: 10.33073/pjm-2021-010. Epub 2021 Mar 19.
Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an important bacterium of nosocomial infections. In this study, CRKP strains, which were mainly isolated from fecal samples of 14 patients in three wards of the hospital in the Silesia Voivodship, rapidly increased from February to August 2018. Therefore, we conducted microbiological and molecular studies of the CRKP isolates analyzed. Colonized patients had critical underlying diseases and comorbidities; one developed bloodstream infection, and five died (33.3%). Antibiotic susceptibilities were determined by the E-test method. A disc synergy test confirmed carbapenemase production. CTX-Mplex PCR evaluated the presence of resistance genes bla CTX-M-type, bla CTX-M-1, bla CTX-M-9, and the genes bla SHV, bla TEM, bla KPC-2, bla NDM-1, bla OXA-48, bla IMP, and bla VIM-1 was detected with the PCR method. Clonality was evaluated by Multi Locus Sequence Typing (MLST) and Pulsed Field Gel Electrophoresis (PFGE). Six (40%) strains were of XDR (Extensively Drug-Resistant) phenotype, and nine (60%) of the isolates exhibited MDR (Multidrug-Resistant) phenotype. The range of carbapenem minimal inhibitory concentrations (MICs, μg/mL) was as follows doripenem (16 to >32), ertapenem (> 32), imipenem (4 to > 32), and meropenem (> 32). PCR and sequencing confirmed the bla CTX-M-15, bla KPC-2, bla OXA-48, and bla VIM-1 genes in all strains. The isolates formed one large PFGE cluster (clone A). MLST assigned them to the emerging high-risk clone of ST147 (CC147) pandemic lineage harboring the bla OXA-48 gene. This study showed that the K. pneumoniae isolates detected in the multi-profile medical centre in Katowice represented a single strain of the microorganism spreading in the hospital environment.