Characterization of Isolates Associated with Emergence of OXA-48-Producing Klebsiella pneumoniae in Croatia

Marko Jelić; Jasenka Škrlin; Danijela Bejuk; Iva Košćak; Iva Butić; Marija Gužvinec; Arjana Tambić-Andrašević

doi:10.1089/mdr.2017.0168

Characterization of Isolates Associated with Emergence of OXA-48-Producing Klebsiella pneumoniae in Croatia

Microb Drug Resist. 2018 Sep;24(7):973-979. doi: 10.1089/mdr.2017.0168. Epub 2017 Dec 21.

Authors

Marko Jelić¹, Jasenka Škrlin², Danijela Bejuk³, Iva Košćak⁴, Iva Butić¹, Marija Gužvinec¹, Arjana Tambić-Andrašević¹

Affiliations

¹ 1 Department of Clinical Microbiology, University Hospital for Infectious Diseases , Zagreb, Croatia .
² 2 Department of Clinical Microbiology and Hospital Infections, Dubrava University Hospital , Zagreb, Croatia .
³ 3 Department of Clinical Microbiology and Hospital Infections, Clinical Hospital "Sveti Duh ," Zagreb, Croatia .
⁴ 4 Department of Medical Microbiology, Public Health Institute of County Varaždin , Varaždin, Croatia .

PMID: 29267137
DOI: 10.1089/mdr.2017.0168

Abstract

Here, we report a retrospective study conducted to elucidate emergence, epidemiology, and molecular mechanisms of resistance underlying the early spread of OXA-48 carbapenemase-producing Enterobacteriaceae in Croatia. Retrospective screening for OXA-48 producers was performed on a collection of 296 nonrepetitive, carbapenem-nonsusceptible enterobacterial isolates collected from January 2011 to December 2012 from 40 participating centers in Croatia. Antimicrobial susceptibility profiles and production of carbapenemases were assessed phenotypically. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing were used for epidemiological analysis. Resistance genes were characterized by polymerase chain reaction (PCR) and sequencing. Plasmid localization of bla_OXA-48 in isolates and transconjugants was investigated by S1-PFGE and Southern hybridization. PCR mapping was used for identification of genetic platform surrounding bla_OXA-48. Out of 296 carbapenem-nonsusceptible isolates, bla_OXA-48 gene was detected in 12 Klebsiella pneumoniae isolates. All OXA-48-producing isolates showed varying resistance to carbapenems and 11 were multidrug resistant. All coproduced additional beta-lactamases, including CTX-M-15, which was detected in eight isolates. Isolates were delineated in five clonal types by PFGE corresponding to five sequence types (STs) assigned ST15, ST16, ST37, ST528, and ST1418. All OXA-48 isolates conjugated successfully and other resistance determinants were not cotransferred. bla_OXA-48 was carried on a ∼60 kb IncL/M plasmid and was detected within Tn1999.2 composite transposon. OXA-48, a class D carbapenemase, is emerging as a potentially significant contributor among carbapenem-resistant Enterobacteriaceae in Croatia, alongside class A and B carbapenemases. Polyclonal genetic background of K. pneumoniae isolates carrying ∼60 kb incL/M plasmid indicates that dissemination of the bla_OXA48 gene is not driven exclusively by the spread of a single clone.

Keywords: Croatia; IncL/M; Klebsiella pneumoniae; OXA-48; Tn1999.2.

MeSH terms

Anti-Bacterial Agents / pharmacology
Bacterial Proteins / genetics
Carbapenems / pharmacology
Croatia
Humans
Klebsiella Infections / drug therapy
Klebsiella Infections / microbiology
Klebsiella pneumoniae / drug effects
Klebsiella pneumoniae / genetics*
Klebsiella pneumoniae / isolation & purification*
Microbial Sensitivity Tests / methods
Multilocus Sequence Typing / methods
Plasmids / genetics
Retrospective Studies
beta-Lactamases / genetics*

Substances

Anti-Bacterial Agents
Bacterial Proteins
Carbapenems
beta-Lactamases
carbapenemase
oxacillinase