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OXA-48-like carbapenemases: the phantom menace
Laurent Poirel1, Anaïs Potron, Patrice Nordmann
1Service de Bactériologie-Virologie, INSERM U914 Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Faculté de Médecine et Université Paris-Sud, 94275 K.-Bicêtre, France. laurent.poirel@bct.aphp.fr
The Journal of Antimicrobial Chemotherapy
|April 14, 2012
Summary
OXA-48-like carbapenemases are spreading in enterobacteria, often on plasmids. Their detection is challenging due to varied resistance profiles, necessitating improved screening methods to control dissemination.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- OXA-48-type carbapenem-hydrolysing class D β-lactamases are emerging threats in Enterobacteriaceae.
- Six variants exist, with OXA-48 being most prevalent, differing by minor amino acid changes.
Purpose of the Study:
- To review the characteristics, genetic basis, and epidemiology of OXA-48-like carbapenemases.
- To highlight challenges in their detection and emphasize the need for effective control strategies.
Main Methods:
- Literature review and analysis of existing data on OXA-48-like β-lactamases.
- Examination of genetic elements (plasmids, insertion sequences) associated with bla(OXA-48)-type genes.
Main Results:
- OXA-48-like enzymes confer varying resistance levels to β-lactams, often sparing cephalosporins.
- bla(OXA-48) genes are plasmid-borne, frequently disseminated by a specific IncL/M plasmid.
- Geographic reservoirs include North Africa, the Middle East, Turkey, and India, with increasing European prevalence.
Conclusions:
- The subtle resistance profiles of many OXA-48-like producers complicate detection.
- Effective screening and detection methods are crucial for preventing further spread and managing outbreaks.
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