Rapid, sensitive and specific detection of OXA-48-like-producing Enterobacteriaceae by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

J Microbiol Methods. 2014 Oct:105:88-91. doi: 10.1016/j.mimet.2014.07.004. Epub 2014 Jul 9.

Abstract

The emergence of Enterobacteriaceae producing the class D carbapenemase OXA-48 has become a public health concern, particularly in southern Europe and in the Mediterranean area. The existing MALDI-TOF MS assays that detect carbapenemase activity have disregarded the Enterobacteriaceae producing OXA-48-like enzymes. Here, we assessed the ability of an optimized MALDI-TOF MS imipenem hydrolysis assay to detect OXA-48-like-producing Enterobacteriaceae. We tested 372 non duplicate isolates of Enterobacteriaceae from 9 species, among which 92 harbored a blaOXA-48-like gene and 180 were non-susceptible to ertapenem. The vast majority (98.9%) of the OXA-48-like producers were detected and 97.8% of the ertapenem non-susceptible isolates were correctly classified. From the agar plate to the final result, the turnaround time of the test was 90min. This quick, easy and accurate MALDI-TOF MS test can expedite the implementation of hygiene measures to prevent dissemination of OXA-48-like-producing Enterobacteriaceae and limit outbreaks.

Keywords: Carbapenemase; Infection control; Klebsiella pneumoniae; MALDI-TOF MS.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / metabolism*
  • Enterobacteriaceae / enzymology*
  • Enterobacteriaceae / isolation & purification
  • Enterobacteriaceae / metabolism*
  • Enterobacteriaceae Infections / microbiology
  • Humans
  • Imipenem / metabolism*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods*
  • Time Factors
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Imipenem
  • beta-Lactamases
  • oxacillinase