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Han N, Li J, Wan P, Pan Y, Xu T, Xiong W, Zeng Z. Co-Existence of Oxazolidinone Resistance Genes cfr(D) and optrA on Two Streptococcus parasuis Isolates from Swine. Antibiotics (Basel) 2023; 12:antibiotics12050825. [PMID: 37237728 DOI: 10.3390/antibiotics12050825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 04/13/2023] [Accepted: 04/19/2023] [Indexed: 05/28/2023] Open
Abstract
This study was performed to investigate the presence and characteristics of the oxazolidinone resistance genes optrA and cfr(D) in Streptococcus parasuis. In total, 36 Streptococcus isolates (30 Streptococcus suis isolates, 6 Streptococcus parasuis isolates) were collected from pig farms in China in 2020-2021, using PCR to determine the presence of optrA and cfr. Then, 2 of the 36 Streptococcus isolates were further processed as follows. Whole-genome sequencing and de novo assembly were employed to analyze the genetic environment of the optrA and cfr(D) genes. Conjugation and inverse PCR were employed to verify the transferability of optrA and cfr(D). The optrA and cfr(D) genes were identified in two S. parasuis strains named SS17 and SS20, respectively. The optrA of the two isolates was located on chromosomes invariably associated with the araC gene and Tn554, which carry the resistance genes erm(A) and ant(9). The two plasmids that carry cfr(D), pSS17 (7550 bp) and pSS20-1 (7550 bp) have 100% nucleotide sequence identity. The cfr(D) was flanked by GMP synthase and IS1202. The findings of this study extend the current knowledge of the genetic background of optrA and cfr(D) and indicate that Tn554 and IS1202 may play an important role in the transmission of optrA and cfr(D), respectively.
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Affiliation(s)
- Ning Han
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Jie Li
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Peng Wan
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Yu Pan
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Tiantian Xu
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Wenguang Xiong
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Zhenling Zeng
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
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Occurrence of cfr-Positive Linezolid-Susceptible Staphylococcus aureus and Non- aureus Staphylococcal Isolates from Pig Farms. Antibiotics (Basel) 2023; 12:antibiotics12020359. [PMID: 36830270 PMCID: PMC9952267 DOI: 10.3390/antibiotics12020359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/11/2023] Open
Abstract
The emergence and spread of cfr-mediated resistance to linezolid in staphylococci have become a serious global concern. The acquisition of cfr confers multidrug resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins, and streptogramin A (PhLOPSA phenotype). However, occurrence of cfr-positive and linezolid-susceptible staphylococci has been identified. To investigate the mechanism underlying linezolid susceptibility in cfr-positive Staphylococcus aureus and non-aureus staphylococci (NAS) isolates from pig farms in Korea. Eleven cfr-positive and linezolid-susceptible staphylococci were analyzed for mutations in domain V of 23S rRNA, ribosomal proteins (L3, L4, and L22), cfr open reading frames (ORFs), and cfr promoter regions. The effect of the cfr mutation (Q148K) on the PhLOPSA phenotype was determined using plasmid constructs expressing either the mutated (cfrQ148K) or nonmutated cfr genes. All 11 (six S. aureus and five NAS) cfr-positive and linezolid-susceptible isolates had a point mutation at position 442 in cfr ORFs (C to A) that resulted in the Q148K mutation. No mutations were detected in 23S rRNA, L3, L4, or L22. The Q148K mutation in Cfr is responsible for phenotypes susceptible to PhLOPSA antimicrobial agents. To our knowledge, this is the first study to report the causal role of a single nucleotide mutation (Q148K) in cfr of S. aureus and NAS isolates in PhLOPSA resistance. Continued nationwide surveillance is necessary to monitor the occurrence and dissemination of mutations in cfr that affect resistance phenotypes in staphylococci of human and animal origin.
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Mobile Oxazolidinone Resistance Genes in Gram-Positive and Gram-Negative Bacteria. Clin Microbiol Rev 2021; 34:e0018820. [PMID: 34076490 DOI: 10.1128/cmr.00188-20] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Seven mobile oxazolidinone resistance genes, including cfr, cfr(B), cfr(C), cfr(D), cfr(E), optrA, and poxtA, have been identified to date. The cfr genes code for 23S rRNA methylases, which confer a multiresistance phenotype that includes resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins, and streptogramin A compounds. The optrA and poxtA genes code for ABC-F proteins that protect the bacterial ribosomes from the inhibitory effects of oxazolidinones. The optrA gene confers resistance to oxazolidinones and phenicols, while the poxtA gene confers elevated MICs or resistance to oxazolidinones, phenicols, and tetracycline. These oxazolidinone resistance genes are most frequently found on plasmids, but they are also located on transposons, integrative and conjugative elements (ICEs), genomic islands, and prophages. In these mobile genetic elements (MGEs), insertion sequences (IS) most often flanked the cfr, optrA, and poxtA genes and were able to generate translocatable units (TUs) that comprise the oxazolidinone resistance genes and occasionally also other genes. MGEs and TUs play an important role in the dissemination of oxazolidinone resistance genes across strain, species, and genus boundaries. Most frequently, these MGEs also harbor genes that mediate resistance not only to antimicrobial agents of other classes, but also to metals and biocides. Direct selection pressure by the use of antimicrobial agents to which the oxazolidinone resistance genes confer resistance, but also indirect selection pressure by the use of antimicrobial agents, metals, or biocides (the respective resistance genes against which are colocated on cfr-, optrA-, or poxtA-carrying MGEs) may play a role in the coselection and persistence of oxazolidinone resistance genes.
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Almeida LM, Gaca A, Bispo PM, Lebreton F, Saavedra JT, Silva RA, Basílio-Júnior ID, Zorzi FM, Filsner PH, Moreno AM, Gilmore MS. Coexistence of the Oxazolidinone Resistance-Associated Genes cfr and optrA in Enterococcus faecalis From a Healthy Piglet in Brazil. Front Public Health 2020; 8:518. [PMID: 33102417 PMCID: PMC7546817 DOI: 10.3389/fpubh.2020.00518] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 08/11/2020] [Indexed: 12/15/2022] Open
Abstract
Oxazolidinones are one of the most important antimicrobials potentially active against glycopeptide- and β-lactam-resistant Gram-positive pathogens. Linezolid—the first oxazolidinone to be approved for clinical use in 2000 by the US Food and Drug Administration—and the newer molecule in the class, tedizolid, inhibit protein synthesis by suppressing the formation of the 70S ribosomal complex in bacteria. Over the past two decades, transferable oxazolidinone resistance genes, in particular cfr and optrA, have been identified in Firmicutes isolated from healthcare-related infections, livestock, and the environment. Our goals in this study were to investigate the genetic contexts and the transferability of the cfr and optrA genes and examine genomic features, such as antimicrobial resistance genes, plasmid incompatibility types, and CRISPR-Cas defenses of a linezolid-resistant Enterococcus faecalis isolated in feces from a healthy pig during an antimicrobial surveillance program for animal production in Brazil. The cfr gene was found to be integrated into a transposon-like structure of 7,759 nt flanked by IS1216E and capable of excising and circularizing, distinguishing it from known genetic contexts for cfr in Enterococcus spp., while optrA was inserted into an Inc18 broad host-range plasmid of >58 kb. Conjugal transfer of cfr and optrA was shown by filter mating. The coexistence of cfr and optrA in an E. faecalis isolated from a healthy nursery pig highlights the need for monitoring the use of antibiotics in the Brazilian swine production system for controlling spread and proliferation of antibiotic resistance.
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Affiliation(s)
- Lara M Almeida
- Institute of Pharmaceutical Sciences, Federal University of Alagoas, Maceió, Brazil.,Department of Clinical and Toxicological Analyses, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Anthony Gaca
- Department of Ophthalmology and Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | - Paulo M Bispo
- Department of Ophthalmology and Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | - François Lebreton
- Department of Ophthalmology and Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | - Jose T Saavedra
- Department of Ophthalmology and Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | - Rafael A Silva
- Institute of Pharmaceutical Sciences, Federal University of Alagoas, Maceió, Brazil
| | | | - Felipe M Zorzi
- School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Pedro H Filsner
- School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Andrea M Moreno
- School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Michael S Gilmore
- Department of Ophthalmology and Department of Microbiology, Harvard Medical School, Boston, MA, United States
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Chen L, Han D, Tang Z, Hao J, Xiong W, Zeng Z. Co-existence of the oxazolidinone resistance genes cfr and optrA on two transferable multi-resistance plasmids in one Enterococcus faecalis isolate from swine. Int J Antimicrob Agents 2020; 56:105993. [PMID: 32335280 DOI: 10.1016/j.ijantimicag.2020.105993] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 02/12/2020] [Accepted: 04/15/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To identify and characterize oxazolidinone resistance genes cfr and optrA in enterococcal isolates. METHODS Two hundred and ninety-three enterococcal isolates were screened for the presence of cfr and optrA by polymerase chain reaction. The transferability of cfr and optrA was examined by conjugation. S1 nuclease pulsed-field gel electrophoresis and Southern blotting were used to identify the location of cfr and optrA. One Enterococcus faecalis isolate carrying both cfr and optrA was sequenced in full. RESULTS cfr and optrA were detected in 16 (5.5%) and 170 (58.0%) enterococcal isolates, respectively. Sixteen enterococcal isolates (E. faecalis n=13, Enterococcus avium n=2, Enterococcus mundtii n=1) carried both cfr and optrA. The cfr-carrying fragment between res and theta in plasmid p4 showed 98.9% identity to the corresponding region of plasmid pEF120805 from vancomycin-resistant Enterococcus faecium. The optrA-carrying segment between tnpB and optrA in plasmid p1 showed >99.9% identity to the corresponding region of genomic DNA from E. faecalis A101. Plasmid p4 and plasmid p1 were simultaneously conjugated to E. faecalis JH2-2. CONCLUSIONS One hundred and seventy optrA-positive enterococci were identified in 293 enterococcal isolates from swine and the farm environment. The co-existence of cfr and optrA in E. avium and E. mundtii has been identified previously. cfr and optrA were identified on two new conjugative plasmids from one E. faecalis isolate. The optrA-carrying segment (IS1216E-optrA-IS1216E) was reported initially. Among different types of enterococcal plasmids, ISEnfa5 and IS1216E elements may play a vital role in the dissemination of cfr and optrA, respectively.
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Affiliation(s)
- Lin Chen
- Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou, Guangdong, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, Guangdong, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Dongdong Han
- Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou, Guangdong, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, Guangdong, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Ziyun Tang
- Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou, Guangdong, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, Guangdong, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Jie Hao
- Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou, Guangdong, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, Guangdong, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China
| | - Wenguang Xiong
- Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou, Guangdong, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, Guangdong, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China.
| | - Zhenling Zeng
- Guangdong Provincial Key Laboratory of Veterinary Drugs Development and Safety Evaluation, South China Agricultural University, Guangzhou, Guangdong, China; National Laboratory of Safety Evaluation (Environmental Assessment) of Veterinary Drugs, South China Agricultural University, Guangzhou, Guangdong, China; National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong, China.
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Guerin F, Sassi M, Dejoies L, Zouari A, Schutz S, Potrel S, Auzou M, Collet A, Lecointe D, Auger G, Cattoir V. Molecular and functional analysis of the novel cfr(D) linezolid resistance gene identified in Enterococcus faecium. J Antimicrob Chemother 2020; 75:1699-1703. [DOI: 10.1093/jac/dkaa125] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 02/08/2020] [Accepted: 03/10/2020] [Indexed: 12/17/2022] Open
Abstract
Abstract
Objectives
To characterize the novel cfr(D) gene identified in an Enterococcus faecium clinical isolate (15-307.1) collected from France.
Methods
The genome of 15-307.1 was entirely sequenced using a hybrid approach combining short-read (MiSeq, Illumina) and long-read (GridION, Oxford Nanopore Technologies) technologies in order to analyse in detail the genetic support and environment of cfr(D). Transfer of linezolid resistance from 15-307.1 to E. faecium BM4107 was attempted by filter-mating experiments. The recombinant plasmid pAT29Ωcfr(D), containing cfr(D) and its own promoter, was transferred to E. faecium HM1070, Enterococcus faecalis JH2-2 and Escherichia coli AG100A.
Results
As previously reported, 15-307.1 belonged to ST17 and was phenotypically resistant to linezolid (MIC, 16 mg/L), vancomycin and teicoplanin. A hybrid sequencing approach confirmed the presence of several resistance genes including vanA, optrA and cfr(D). Located on a 103 kb plasmid, cfr(D) encoded a 357 amino acid protein, which shared 64%, 64%, 48% and 51% amino acid identity with Cfr, Cfr(B), Cfr(C) and Cfr(E), respectively. Both optrA and cfr(D) were successfully co-transferred to E. faecium BM4107. When expressed in E. faecium HM1070 and E. faecalis JH2-2, pAT29Ωcfr(D) did not confer any resistance, whereas it was responsible for an expected PhLOPSA resistance phenotype in E. coli AG100A. Analysis of the genetic environment of cfr(D) showed multiple IS1216 elements, putatively involved in its mobilization.
Conclusions
Cfr(D) is a novel member of the family of 23S rRNA methyltransferases. While only conferring a PhLOPSA resistance phenotype when expressed in E. coli, enterococci could constitute an unknown reservoir of cfr(D).
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Affiliation(s)
- François Guerin
- CHU de Caen, Service de Microbiologie, Caen, France
- Université de Caen Normandie, EA4655 Caen, France
| | - Mohamed Sassi
- Université de Rennes 1, Inserm U1230, Rennes, France
| | - Loren Dejoies
- Université de Rennes 1, Inserm U1230, Rennes, France
- CHU de Rennes, Service de Bactériologie-Hygiène hospitalière, Rennes, France
| | - Asma Zouari
- CHU de Rennes, Service de Bactériologie-Hygiène hospitalière, Rennes, France
- CNR de la Résistance aux Antibiotiques (laboratoire associé ‘Entérocoques’), Rennes, France
| | - Sacha Schutz
- CHU de Rennes, Service de Génétique moléculaire et Génomique médicale, Rennes, France
| | - Sophie Potrel
- CHU de Rennes, Service de Bactériologie-Hygiène hospitalière, Rennes, France
- CNR de la Résistance aux Antibiotiques (laboratoire associé ‘Entérocoques’), Rennes, France
| | - Michel Auzou
- CHU de Caen, Service de Microbiologie, Caen, France
| | - Anaïs Collet
- CHU de Rennes, Service de Bactériologie-Hygiène hospitalière, Rennes, France
- CNR de la Résistance aux Antibiotiques (laboratoire associé ‘Entérocoques’), Rennes, France
| | - Didier Lecointe
- Unité Fonctionnelle d’Hygiène Hospitalière et de Lutte contre les Infections Nosocomiales, Centre Hospitalier Sud Francilien, Corbeil-Essonnes, France
| | - Gabriel Auger
- CHU de Rennes, Service de Bactériologie-Hygiène hospitalière, Rennes, France
- CNR de la Résistance aux Antibiotiques (laboratoire associé ‘Entérocoques’), Rennes, France
| | - Vincent Cattoir
- Université de Rennes 1, Inserm U1230, Rennes, France
- CHU de Rennes, Service de Bactériologie-Hygiène hospitalière, Rennes, France
- CNR de la Résistance aux Antibiotiques (laboratoire associé ‘Entérocoques’), Rennes, France
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Nordmann P, Rodríguez-Villodres A, Poirel L. A selective culture medium for screening linezolid-resistant gram-positive bacteria. Diagn Microbiol Infect Dis 2019; 95:1-4. [PMID: 30981556 DOI: 10.1016/j.diagmicrobio.2019.03.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/14/2019] [Accepted: 03/16/2019] [Indexed: 12/13/2022]
Abstract
The SuperLinezolid medium was developed for screening resistance to linezolid (LZD) in Gram-positive bacteria (Staphylococcus spp., Enterococcus spp.). It was evaluated using LZD-susceptible (n = 20) and LZD-resistant (n = 17) Gram-positive isolates. The sensitivity was found to be 82% at 24 h (3 out of 17 isolates being missed), and reached 100% at 48 h. At 48 h, a single LZD-susceptible isolate grew (specificity 95%). By testing stools spiked with LZD-resistant Gram-positive strains, an excellent performance of the medium was observed, with a lowest detection limit ranging from 101 to 102 CFU/ml. Overall, this medium is accurate for detection of LZD-resistant Gram-positive isolates after 24 h of culture.
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Affiliation(s)
- Patrice Nordmann
- Medical and Molecular Microbiology Unit, Department of Medicine, Faculty of Science, University of Fribourg, Fribourg, Switzerland; INSERM European Unit (IAME, France), University of Fribourg; Swiss National Reference Center for Emerging Antibiotic Resistance (NARA), Fribourg, Switzerland; Institute for Microbiology, University of Lausanne and University Hospital Centre, Lausanne, Switzerland.
| | - Angel Rodríguez-Villodres
- Medical and Molecular Microbiology Unit, Department of Medicine, Faculty of Science, University of Fribourg, Fribourg, Switzerland; Clinical Unit of Infectious Diseases, Microbiology and Preventive Medicine, University Hospital Virgen del Rocío, Seville, Spain; Institute of Biomedicine of Seville (IBiS), University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
| | - Laurent Poirel
- Medical and Molecular Microbiology Unit, Department of Medicine, Faculty of Science, University of Fribourg, Fribourg, Switzerland; INSERM European Unit (IAME, France), University of Fribourg; Swiss National Reference Center for Emerging Antibiotic Resistance (NARA), Fribourg, Switzerland
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