Molecular epidemiology of carbapenemase-producing Enterobacteriaceae infection/colonisation in a hospital in Madrid

Abstract

Introduction: A description is presented on the molecular epidemiology of carbapenemase-producing enterobacteriaceae infection in a tertiary hospital.

Material and methods: A study was made on all the carbapenemase-producing enterobacteriaceae isolations obtained between February 2015 and March 2016 in the Hospital Universitario 12 de Octubre (Madrid). Phenotypic and molecular methods were used.

Results: A total of 7 bacterial species were identified, with the majority being Klebsiella pneumoniae (K. pneumoniae) (78.9%) and Enterobacter cloacae (E. cloacae) (16.4%). The resistance of K. pneumoniae and E. cloacae for carbapenems was 88.7 and 88.6% for ertapenem, 21.4 and 54.3% for imipenem, and 20.8 and 34.3% for meropenem, respectively. The most frequent carbapenemase type was OXA-48 (91.1%) and VIM (71.4%) in E. cloacae. A total of 9K. pneumoniae clonal types were identified, including a majority pertaining to the sequence type ST11. In E. cloacae, 16 clonal types were identified.

Conclusions: The current increase in carbapenemase-producing enterobacteriaceae is mainly due to the spread of OXA-48-producing K. pneumoniae.

Keywords: Carbapenemasas; Carbapenemases; Enterobacteria; Enterobacterias; Epidemiología molecular; Klebsiella pneumoniae; Molecular epidemiology; OXA-48.