[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]
Novel multiresistance cfr plasmids in linezolid-resistant methicillin-resistant Staphylococcus epidermidis and vancomycin-resistant Enterococcus faecium (VRE) from a hospital outbreak: co-location of cfr and optrA in VRE
Alexandros Lazaris, David C. Coleman, Angela M. Kearns, Bruno Pichon, Peter M. Kinnevey, Megan R. Earls, Breida Boyle, Brian O’Connell, Gráinne I. Brennan, Anna C. Shore Anna
Journal of Antimicrobial Chemotherapy, dkx292, https://doi.org/10.1093/jac/dkx292
Published: 28 August 2017 – Received: 09 June 2017 – Revision Requested: 30 June 2017 – Revision Received: 19 July 2017 – Accepted: 19 July 2017
Citation: Alexandros Lazaris, David C. Coleman, Angela M. Kearns, Bruno Pichon, Peter M. Kinnevey, Megan R. Earls, Breida Boyle, Brian O’Connell, Gráinne I. Brennan, Anna C. Shore; Novel multiresistance cfr plasmids in linezolid-resistant methicillin-resistant Staphylococcus epidermidis and vancomycin-resistant Enterococcus faecium (VRE) from a hospital outbreak: co-location of cfr and optrA in VRE, Journal of Antimicrobial Chemotherapy, , dkx292, https://doi.org/10.1093/jac/dkx292
© 2017 Oxford University Press
Linezolid is often the drug of last resort to treat infections caused by Gram-positive cocci. Linezolid resistance can be mutational (23S rRNA or L-protein) or, less commonly, acquired [predominantly cfr, conferring resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins and streptogramin A compounds (PhLOPSA) or optrA, encoding oxazolidinone and phenicol resistance].
To investigate the clonality and genetic basis of linezolid resistance in 13 linezolid-resistant (LZDR) methicillin-resistant Staphylococcus epidermidis (MRSE) isolates recovered during a 2013/14 outbreak in an ICU in an Irish hospital and an LZDR vancomycin-resistant Enterococcus faecium (VRE) isolate from an LZDR-MRSE-positive patient.
All isolates underwent PhLOPSA susceptibility testing, 23S rRNA sequencing, DNA microarray profiling and WGS.
All isolates exhibited the PhLOPSA phenotype. The VRE harboured cfr and optrA on a novel 73 kb plasmid (pEF12-0805) also encoding erm(A), erm(B), lnu(B), lnu(E), aphA3 and aadE. One MRSE (M13/0451, from the same patient as the VRE) harboured cfr on a novel 8.5 kb plasmid (pSEM13-0451). The remaining 12 MRSE lacked cfr but exhibited linezolid resistance-associated mutations and were closely related to (1–52 SNPs) but distinct from M13/0451 (202–223 SNPs).
Using WGS, novel and distinct cfr and cfr/optrA plasmids were identified in an MRSE and VRE isolate, respectively, as well as a cfr-negative LZDR-MRSE ICU outbreak and a distinct cfr-positive LZDR-MRSE from the same ICU. To our knowledge, this is the first report of cfr and optrA on a single VRE plasmid. Ongoing surveillance of linezolid resistance is essential to maintain its therapeutic efficacy.
Topic: phenotype – mutation – plasmids – disease outbreaks – gram-positive cocci – intensive care unit – methicillin – oxazolidinones – single nucleotide polymorphism – rna, ribosomal, 23s – staphylococcus epidermidis – streptogramin a – infection – genetics – linezolid – dna microarrays – lincosamide – surveillance, medical – enterococcus, vancomycin-resistant – clonality (genetic analysis) – pleuromutilins
Issue Section: ORIGINAL RESEARCH
© The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Keywords: Antibiotics; Drugs Resistance; Enterococcus faecium; Staphylococcus Epidermidis; Vancomycin; Nosocomial Outbreaks.