title: OXA-48-like carbapenemases: the phantom menace.
abstract: OXA-48-type carbapenem-hydrolysing class D β-lactamases are increasingly reported in enterobacterial species. To date, six OXA-48-like variants have been identified, with OXA-48 being the most widespread. They differ by a few amino acid substitutions or deletions (one to five amino acids). The enzymes hydrolyse penicillins at a high level and carbapenems at a low level, sparing broad-spectrum cephalosporins, and are not susceptible to β-lactamase inhibitors. When combining permeability defects, OXA-48-like producers may exhibit a high level of resistance to carbapenems. OXA-163 is an exception, hydrolysing broad-spectrum cephalosporins but carbapenems at a very low level, and being susceptible to β-lactamase inhibitors. The bla(OXA-48)-type genes are always plasmid-borne and have been identified in association with insertion sequences involved in their acquisition and expression. The current spread of the bla(OXA-48) gene is mostly linked to the dissemination of a single IncL/M-type self-transferable plasmid of 62 kb that does not carry any additional resistance gene. OXA-48-type carbapenemases have been identified mainly from North African countries, the Middle East, Turkey and India, those areas constituting the most important reservoirs; however, occurrence of OXA-48 producers in European countries is now well documented, with some reported hospital outbreaks. Since many OXA-48-like producers do not exhibit resistance to broad-spectrum cephalosporins, or only decreased susceptibility to carbapenems, their recognition and detection can be challenging. Adequate screening and detection methods are therefore required to prevent and control their dissemination.
authors.affiliation: Service 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
authors.forename: Laurent
authors.initials: L
authors.lastname: Poirel
authors.forename: Anaïs
authors.initials: A
authors.lastname: Potron
authors.forename: Patrice
authors.initials: P
authors.lastname: Nordmann
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D015780:Carbapenems / Q000378:metabolism; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology*; D022761:Gene Transfer, Horizontal; D014943:Global Health; D006801:Humans; D006868:Hydrolysis; D010406:Penicillins / Q000378:metabolism; D010957:Plasmids; D015995:Prevalence; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D010406:Penicillins; D001618:beta-Lactamases; C063912:carbapenemase