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Liu C, Yu J, Chen C, Li X, Ye Y, Dong Y, Ying X, Li H, Wang W. Characterization of linezolid- and methicillin-resistant coagulase-negative staphylococci in a tertiary hospital in China. BMC Infect Dis 2024; 24:486. [PMID: 38730362 PMCID: PMC11088155 DOI: 10.1186/s12879-024-09376-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 05/03/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Recently, linezolid-resistant staphylococci have become an emerging problem worldwide. Understanding the mechanisms of resistance, molecular epidemiology and transmission of linezolid-resistant CoNS in hospitals is very important. METHODS The antimicrobial susceptibilities of all isolates were determined by the microdilution method. The resistance mechanisms and molecular characteristics of the strains were determined using whole-genome sequencing and PCR. RESULTS All the strains were resistant to oxacillin and carried the mecA gene; 13 patients (36.1%) had prior linezolid exposure. Most S. epidermidis and S. hominis isolates were ST22 and ST1, respectively. MLST typing and evolutionary analysis indicated most linezolid-resistant CoNS strains were genetically related. In this study, we revealed that distinct CoNS strains have different mechanisms of linezolid resistance. Among ST22-type S. epidermidis, acquisition of the T2504A and C2534T mutations in the V domain of the 23 S rRNA gene, as well as mutations in the ribosomal proteins L3 (L101V, G152D, and D159Y) and L4 (N158S), were linked to the development of linezolid resistance. In S. cohnii isolates, cfr, S158Y and D159Y mutations in the ribosomal protein L3 were detected. Additionally, emergence of the G2576T mutation and the cfr gene were major causes of linezolid resistance in S. hominis isolates. The cfr gene, G2576T and C2104T mutations, M156T change in L3 protein, and I188S change in L4 protein were found in S. capitis isolates. CONCLUSION The emergence of linezolid-resistant CoNS in the environment is concerning because it involves clonal dissemination and frequently coexists with various drug resistance mechanisms.
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Affiliation(s)
- Cailin Liu
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Erqi District, Zhengzhou, Henan Province, 450052, China
- Key Clinical Laboratory of Henan Province, Zhengzhou, China
| | - Jing Yu
- Department of Clinical Laboratory, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Chunguang Chen
- Department of Clinical Laboratory, The Sixth People's Hospital of Zhengzhou City, Zhengzhou, China
| | - Xiaogai Li
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Erqi District, Zhengzhou, Henan Province, 450052, China
- Key Clinical Laboratory of Henan Province, Zhengzhou, China
| | - Yafei Ye
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Erqi District, Zhengzhou, Henan Province, 450052, China
- Key Clinical Laboratory of Henan Province, Zhengzhou, China
| | - Yani Dong
- Department of Clinical Laboratory, Yichuan People's Hospital, Zhengzhou, China
| | - Xinxin Ying
- Department of Clinical Laboratory, Luohe Sixth People's Hospital, Zhengzhou, China
| | - Haijun Li
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Erqi District, Zhengzhou, Henan Province, 450052, China
- Key Clinical Laboratory of Henan Province, Zhengzhou, China
| | - Wanhai Wang
- Department of Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Erqi District, Zhengzhou, Henan Province, 450052, China.
- Key Clinical Laboratory of Henan Province, Zhengzhou, China.
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Tessier E, Ruffier d'Epenoux L, Lartigue MF, Chaufour L, Plouzeau-Jayle C, Chenouard R, Guérin F, Tandé D, Lamoureux C, Bémer P, Corvec S. Comparison of the in vitro activities of delafloxacin and comparators against Staphylococcus epidermidis clinical strains involved in osteoarticular infections: a CRIOGO multicentre retrospective study. J Antimicrob Chemother 2024; 79:1045-1050. [PMID: 38507272 DOI: 10.1093/jac/dkae071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 02/29/2024] [Indexed: 03/22/2024] Open
Abstract
OBJECTIVES Staphylococcus epidermidis bone and joint infections (BJIs) on material are often difficult to treat. The activity of delafloxacin has not yet been studied on S. epidermidis in this context. The aim of this study was to assess its in vitro activity compared with other fluoroquinolones, against a large collection of S. epidermidis clinical strains. METHODS We selected 538 S. epidermidis strains isolated between January 2015 and February 2023 from six French teaching hospitals. One hundred and fifty-two strains were ofloxacin susceptible and 386 were ofloxacin resistant. Identifications were performed by MS and MICs were determined using gradient concentration strips for ofloxacin, levofloxacin, moxifloxacin and delafloxacin. RESULTS Ofloxacin-susceptible strains were susceptible to all fluoroquinolones. Resistant strains had higher MICs of all fluoroquinolones. Strains resistant to ofloxacin (89.1%) still showed susceptibility to delafloxacin when using the Staphylococcus aureus 2021 CA-SFM/EUCAST threshold of 0.25 mg/L. In contrast, only 3.9% of the ofloxacin-resistant strains remained susceptible to delafloxacin with the 0.016 mg/L S. aureus breakpoint according to CA-SFM/EUCAST guidelines in 2022. The MIC50 was 0.094 mg/L and the MIC90 was 0.38 mg/L. CONCLUSIONS We showed low delafloxacin MICs for ofloxacin-susceptible S. epidermidis strains and a double population for ofloxacin-resistant strains. Despite the absence of breakpoints for S. epidermidis, delafloxacin may be an option for the treatment of complex BJI, including strains with MICs of ≤0.094 mg/L, leading to 64% susceptibility. This study underlines the importance for determining specific S. epidermidis delafloxacin breakpoints for the management of BJI on material.
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Affiliation(s)
- E Tessier
- Service de Bactériologie et des Contrôles Microbiologiques, CHU Nantes, Nantes, France
| | - L Ruffier d'Epenoux
- Service de Bactériologie et des Contrôles Microbiologiques, CHU Nantes, Nantes, France
- INSERM, INCIT U1302, CHU Nantes, Université de Nantes, Nantes F-44000, France
| | - M F Lartigue
- Service de Bactériologie-Virologie-Hygiène, CHU Tours, Tours, France
- ISP, UMR1282, Université de Tours, INRAe, Tours, France
| | - L Chaufour
- Service de Bactériologie-Virologie-Hygiène, CHU Tours, Tours, France
| | - C Plouzeau-Jayle
- Service de Bactériologie et d'Hygiène hospitalière, CHU Poitiers, Poitiers, France
| | - R Chenouard
- Service de Bactériologie, CHU Angers, Angers, France
| | - F Guérin
- Service de Bactériologie-Hygiène hospitalière & CNR de la résistance aux Antibiotiques (laboratoire associé 'Entérocoques'), CHU Rennes, Rennes, France
| | - D Tandé
- Unité de Bactériologie, Pôle de Biologie-Pathologie CHU Brest, Brest, France
| | - C Lamoureux
- Unité de Bactériologie, Pôle de Biologie-Pathologie CHU Brest, Brest, France
| | - P Bémer
- Service de Bactériologie et des Contrôles Microbiologiques, CHU Nantes, Nantes, France
| | - S Corvec
- Service de Bactériologie et des Contrôles Microbiologiques, CHU Nantes, Nantes, France
- INSERM, INCIT U1302, CHU Nantes, Université de Nantes, Nantes F-44000, France
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Cinthi M, Coccitto SN, Pocognoli A, Zeni G, Mazzariol A, Di Gregorio A, Vignaroli C, Brenciani A, Giovanetti E. Persistence and evolution of linezolid- and methicillin-resistant Staphylococcus epidermidis ST2 and ST5 clones in an Italian hospital. J Glob Antimicrob Resist 2024; 36:358-364. [PMID: 38331029 DOI: 10.1016/j.jgar.2024.01.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 01/18/2024] [Accepted: 01/30/2024] [Indexed: 02/10/2024] Open
Abstract
OBJECTIVES Staphylococcus epidermidis is a member of the human skin microbiome. However, in recent decades, multidrug-resistant and hospital-adapted S. epidermidis clones are increasingly involved in severe human infections associated with medical devices and in immunocompromised patients. In 2016, we reported that a linezolid- and methicillin-resistant S. epidermidis ST2 clone, bearing the G2576T mutation, was endemic in an Italian hospital since 2004. This study aimed to retrospectively analyse 34 linezolid- and methicillin-resistant S. epidermidis (LR-MRSE) strains collected from 2018 to 2021 from the same hospital. METHODS LR-MRSE were typed by Pulsed-Field Gel Electrophoresis and multilocus sequence typing and screened for transferable linezolid resistance genes. Representative LR-MRSE were subjected to whole-genome sequencing (WGS) and their resistomes, including the presence of ribosomal mechanisms of linezolid resistance and of rpoB gene mutations conferring rifampin resistance, were investigated. RESULTS ST2 lineage was still prevalent (19/34; 55.9%), but, over time, ST5 clone has been widespread too (15/34; 44.1%). Thirteen of the 34 isolates (38.2%) were positive for the cfr gene. Whole-genome sequencing analysis of relevant LR-MRSE displayed complex resistomes for the presence of several acquired antibiotic resistance genes, including the SCCmec type III (3A) and SCCmec type IV (2B) in ST2 and ST5 isolates, respectively. Bioinformatics and polymerase chain reaction (PCR) mapping also showed a plasmid-location of the cfr gene and the occurrence of previously undetected mutations in L3 (ST2 lineage) and L4 (ST3 lineage) ribosomal proteins and substitutions in the rpoB gene. CONCLUSION The occurrence of LR-MRSE should be carefully monitored in order to prevent the spread of this difficult-to-treat pathogen and to preserve the efficacy of linezolid.
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Affiliation(s)
- Marzia Cinthi
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Sonia Nina Coccitto
- Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona, Italy
| | - Antonella Pocognoli
- Clinical Microbiology Laboratory, Azienda Ospedaliero-Universitaria, 'Ospedali Riuniti', Ancona, Italy
| | - Guido Zeni
- Department of Diagnostics and Public Health, Verona University, Verona, Italy
| | - Annarita Mazzariol
- Department of Diagnostics and Public Health, Verona University, Verona, Italy
| | - Alessandra Di Gregorio
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Carla Vignaroli
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Andrea Brenciani
- Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona, Italy.
| | - Eleonora Giovanetti
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
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Kovařovic V, Finstrlová A, Sedláček I, Petráš P, Švec P, Mašlaňová I, Neumann-Schaal M, Šedo O, Botka T, Staňková E, Doškař J, Pantůček R. Staphylococcus brunensis sp. nov. isolated from human clinical specimens with a staphylococcal cassette chromosome-related genomic island outside of the rlmH gene bearing the ccrDE recombinase gene complex. Microbiol Spectr 2023; 11:e0134223. [PMID: 37712674 PMCID: PMC10581047 DOI: 10.1128/spectrum.01342-23] [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: 03/29/2023] [Accepted: 07/03/2023] [Indexed: 09/16/2023] Open
Abstract
Novel species of coagulase-negative staphylococci, which could serve as reservoirs of virulence and antimicrobial resistance factors for opportunistic pathogens from the genus Staphylococcus, are recognized in human and animal specimens due to advances in diagnostic techniques. Here, we used whole-genome sequencing, extensive biotyping, MALDI-TOF mass spectrometry, and chemotaxonomy to characterize five coagulase-negative strains from the Staphylococcus haemolyticus phylogenetic clade obtained from human ear swabs, wounds, and bile. Based on the results of polyphasic taxonomy, we propose the species Staphylococcus brunensis sp. nov. (type strain NRL/St 16/872T = CCM 9024T = LMG 31872T = DSM 111349T). The genomic analysis revealed numerous variable genomic elements, including staphylococcal cassette chromosome (SCC), prophages, plasmids, and a unique 18.8 kb-long genomic island SbCIccrDE integrated into the ribosomal protein L7 serine acetyltransferase gene rimL. SbCIccrDE has a cassette chromosome recombinase (ccr) gene complex with a typical structure found in SCCs. Based on nucleotide and amino acid identity to other known ccr genes and the distinct integration site that differs from the canonical methyltransferase gene rlmH exploited by SCCs, we classified the ccr genes as novel variants, ccrDE. The comparative genomic analysis of SbCIccrDE with related islands shows that they can accumulate virulence and antimicrobial resistance factors creating novel resistance elements, which reflects the evolution of SCC. The spread of these resistance islands into established pathogens such as Staphylococcus aureus would pose a great threat to the healthcare system. IMPORTANCE The coagulase-negative staphylococci are important opportunistic human pathogens, which cause bloodstream and foreign body infections, mainly in immunocompromised patients. The mobile elements, primarily the staphylococcal cassette chromosome mec, which confers resistance to methicillin, are the key to the successful dissemination of staphylococci into healthcare and community settings. Here, we present a novel species of the Staphylococcus genus isolated from human clinical material. The detailed analysis of its genome revealed a previously undescribed genomic island, which is closely related to the staphylococcal cassette chromosome and has the potential to accumulate and spread virulence and resistance determinants. The island harbors a set of conserved genes required for its mobilization, which we recognized as novel cassette chromosome recombinase genes ccrDE. Similar islands were revealed not only in the genomes of coagulase-negative staphylococci but also in S. aureus. The comparative genomic study contributes substantially to the understanding of the evolution and pathogenesis of staphylococci.
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Affiliation(s)
- Vojtěch Kovařovic
- Department of Experimental Biology, Division of Genetics and Molecular Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Adéla Finstrlová
- Department of Experimental Biology, Division of Genetics and Molecular Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Ivo Sedláček
- Department of Experimental Biology, Czech Collection of Microorganisms, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Petr Petráš
- Reference Laboratory for Staphylococci, National Institute of Public Health, Praha, Czech Republic
| | - Pavel Švec
- Department of Experimental Biology, Czech Collection of Microorganisms, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Ivana Mašlaňová
- Department of Experimental Biology, Division of Genetics and Molecular Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Meina Neumann-Schaal
- Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Ondrej Šedo
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Tibor Botka
- Department of Experimental Biology, Division of Genetics and Molecular Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Eva Staňková
- Department of Experimental Biology, Czech Collection of Microorganisms, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Jiří Doškař
- Department of Experimental Biology, Division of Genetics and Molecular Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Roman Pantůček
- Department of Experimental Biology, Division of Genetics and Molecular Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
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Campmann F, Tönnies H, Böing C, Schuler F, Mellmann A, Schwierzeck V. Molecular Characterization of Clinical Linezolid-Resistant Staphylococcus epidermidis in a Tertiary Care Hospital. Microorganisms 2023; 11:1805. [PMID: 37512978 PMCID: PMC10383320 DOI: 10.3390/microorganisms11071805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Staphylococcus epidermidis (S. epidermidis) is part of the human skin flora but can also cause nosocomial infections, such as device-associated infections, especially in vulnerable patient groups. Here, we investigated clinical isolates of linezolid-resistant S. epidermidis (LRSE) collected from blood cultures at the University Hospital Münster (UHM) during the period 2020-2022. All detected isolates were subjected to whole genome sequencing (WGS) and the relatedness of the isolates was determined using core genome multilocus sequence typing (cgMLST). The 15 LRSE isolates detected were classified as multilocus sequence type (ST) 2 carrying the staphylococcal cassette chromosome mec (SCCmec) type III. All isolates showed high-level resistance for linezolid by gradient tests. However, no isolate carried the cfr gene that is often associated with linezolid resistance. Analysis of cgMLST data sets revealed a cluster of six closely related LRSE isolates, suggesting a transmission event on a hematological/oncological ward at our hospital. Among the included patients, the majority of patients affected by LRSE infections had underlying hematological malignancies. This confirms previous observations that this patient group is particularly vulnerable to LRSE infection. Our data emphasize that the surveillance of LRSE in the hospital setting is a necessary step to prevent the spread of multidrug-resistant S. epidermidis among vulnerable patient groups, such as patients with hematological malignancies, immunosuppression or patients in intensive care units.
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Affiliation(s)
- Florian Campmann
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
| | - Hauke Tönnies
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
| | - Christian Böing
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
| | - Franziska Schuler
- Institute for Medical Microbiology, University Hospital Münster, 48149 Münster, Germany
| | - Alexander Mellmann
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
| | - Vera Schwierzeck
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
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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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Spreading of cfr-Carrying Plasmids among Staphylococci from Humans and Animals. Microbiol Spectr 2022; 10:e0246122. [PMID: 36413029 PMCID: PMC9769919 DOI: 10.1128/spectrum.02461-22] [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] [Indexed: 11/23/2022] Open
Abstract
The multidrug resistance gene cfr mediates resistance to multiple antimicrobial agents, including linezolid. Plasmids are the preferred vector for the dissemination of cfr. However, the presence and transmission of cfr-carrying plasmids among staphylococci from humans and animals have rarely been studied. Here, we investigated the presence of the cfr gene in 2,250 staphylococci of human clinical origin collected in Zhejiang, China, in 1998 to 2021 and in 3,329 porcine staphylococci preserved in our laboratories. The cfr gene was detected in 38 human isolates; its presence in Staphylococcus haemolyticus and Staphylococcus cohnii in 2003 was earlier than that identified in 2005, and Staphylococcus capitis (n = 30) was the predominant species. The cfr-carrying fragment in 38 isolates exhibited >99% nucleotide sequence similarity to plasmid pLRSA417 (39,504 bp), which was identified in 2015 and originated from a human clinical methicillin-resistant Staphylococcus aureus isolate from Zhejiang, China. The cfr-carrying plasmids in 18 MinION-sequenced staphylococci ranged in size from 32,697 bp to 43,457 bp. Fifteen plasmids were identical to pLRSA417, except for the inversion of an 8.4-kb segment comprising IS256-aacA/aphD-ISEnfa4_1-cfr-ISEnfa4_2, while the remaining 3 plasmids exhibited slightly different structures. Among the 114 cfr-positive staphylococci from pigs, pLRSA417-like plasmids were detected in 3 isolates. Intraspecies and interspecies conjugation occurred in human-derived pLRSA417-like plasmids. The presence of pLRSA417-like plasmids in staphylococci from multiple geographic regions and different hosts implied the possible transmission of the respective isolates between humans and animals. IMPORTANCE The therapeutic efficacy of the oxazolidinone antimicrobial linezolid is reduced by the emergence and dissemination of the multidrug resistance gene cfr. The cfr-carrying plasmid pLRSA417 was first identified in a clinical methicillin-resistant Staphylococcus aureus isolate, but its presence in staphylococci of human and animal origin has not been reported previously. This study showed that conjugative plasmids similar to pLRSA417 were detected mainly in Staphylococcus capitis and existed in different staphylococci in 2003 to 2021 in various clinical departments in the same hospital. pLRSA417-like plasmids were also present in staphylococci of food animal sources from different geographic regions, which suggested possible transmission among humans and animals.
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Schouls LM, Veldman K, Brouwer MSM, Dierikx C, Witteveen S, van Santen-Verheuvel M, Hendrickx APA, Landman F, Hengeveld P, Wullings B, Rapallini M, Wit B, van Duijkeren E. cfr and fexA genes in methicillin-resistant Staphylococcus aureus from humans and livestock in the Netherlands. COMMUNICATIONS MEDICINE 2022; 2:135. [PMID: 36317053 PMCID: PMC9616846 DOI: 10.1038/s43856-022-00200-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 10/06/2022] [Indexed: 11/09/2022] Open
Abstract
Background Although the Netherlands is a country with a low endemic level of methicillin-resistant Staphylococcus aureus (MRSA), a national MRSA surveillance has been in place since 1989. In 2003 livestock emerged as a major reservoir of MRSA and currently livestock-associated MRSA (clonal complex CC398) make up 25% of all surveillance isolates. To assess possible transfer of resistant strains or resistance genes, MRSA obtained from humans and animals were characterized in detail. Methods The sequenced genomes of 6327 MRSA surveillance isolates from humans and from 332 CC398 isolates from livestock-related samples were analyzed and resistance genes were identified. Several isolates were subjected to long-read sequencing to reconstruct chromosomes and plasmids. Results Here we show the presence of the multi-resistance gene cfr in seven CC398 isolates obtained from humans and in one CC398 isolate from a pig-farm dust sample. Cfr induces resistance against five antibiotic classes, which is true for all but two isolates. The isolates are genetically unrelated, and in seven of the isolates cfr are located on distinct plasmids. The fexA gene is found in 3.9% surveillance isolates and in 7.5% of the samples from livestock. There is considerable sequence variation of fexA and geographic origin of the fexA alleles. Conclusions The rare cfr and fexA resistance genes are found in MRSA from humans and animals in the Netherlands, but there is no evidence for spread of resistant strains or resistance plasmids. The proportion of cfr-positive MRSA is low, but its presence is worrying and should be closely monitored.
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Affiliation(s)
- Leo M. Schouls
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Infectious Diseases Research, Diagnostics and laboratory Surveillance (IDS), Bilthoven, The Netherlands
| | - Kees Veldman
- grid.4818.50000 0001 0791 5666Wageningen Bioveterinary Research (WBVR), Bacteriology, Host Pathogen Interaction & Diagnostics, Lelystad, The Netherlands
| | - Michael S. M. Brouwer
- grid.4818.50000 0001 0791 5666Wageningen Bioveterinary Research (WBVR), Bacteriology, Host Pathogen Interaction & Diagnostics, Lelystad, The Netherlands
| | - Cindy Dierikx
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Zoonoses and Environmental Microbiology (Z&O), Bilthoven, The Netherlands
| | - Sandra Witteveen
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Infectious Diseases Research, Diagnostics and laboratory Surveillance (IDS), Bilthoven, The Netherlands
| | - Marga van Santen-Verheuvel
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Infectious Diseases Research, Diagnostics and laboratory Surveillance (IDS), Bilthoven, The Netherlands
| | - Antoni P. A. Hendrickx
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Infectious Diseases Research, Diagnostics and laboratory Surveillance (IDS), Bilthoven, The Netherlands
| | - Fabian Landman
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Infectious Diseases Research, Diagnostics and laboratory Surveillance (IDS), Bilthoven, The Netherlands
| | - Paul Hengeveld
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Zoonoses and Environmental Microbiology (Z&O), Bilthoven, The Netherlands
| | - Bart Wullings
- grid.4818.50000 0001 0791 5666Wageningen Food Safety Research, Team Bacteriology, Molecular Biology & AMR, Wageningen, The Netherlands
| | - Michel Rapallini
- grid.4818.50000 0001 0791 5666Wageningen Food Safety Research, Team Bacteriology, Molecular Biology & AMR, Wageningen, The Netherlands
| | - Ben Wit
- grid.435742.30000 0001 0726 7822Netherlands Food and Consumer Product Safety Authority (NVWA), Food safety, Apeldoorn, The Netherlands
| | - Engeline van Duijkeren
- grid.31147.300000 0001 2208 0118National Institute for Public Health and the Environment (RIVM), Zoonoses and Environmental Microbiology (Z&O), Bilthoven, The Netherlands
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Brenciani A, Morroni G, Schwarz S, Giovanetti E. Oxazolidinones: mechanisms of resistance and mobile genetic elements involved. J Antimicrob Chemother 2022; 77:2596-2621. [PMID: 35989417 DOI: 10.1093/jac/dkac263] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The oxazolidinones (linezolid and tedizolid) are last-resort antimicrobial agents used for the treatment of severe infections in humans caused by MDR Gram-positive bacteria. They bind to the peptidyl transferase centre of the bacterial ribosome inhibiting protein synthesis. Even if the majority of Gram-positive bacteria remain susceptible to oxazolidinones, resistant isolates have been reported worldwide. Apart from mutations, affecting mostly the 23S rDNA genes and selected ribosomal proteins, acquisition of resistance genes (cfr and cfr-like, optrA and poxtA), often associated with mobile genetic elements [such as non-conjugative and conjugative plasmids, transposons, integrative and conjugative elements (ICEs), prophages and translocatable units], plays a critical role in oxazolidinone resistance. In this review, we briefly summarize the current knowledge on oxazolidinone resistance mechanisms and provide an overview on the diversity of the mobile genetic elements carrying oxazolidinone resistance genes in Gram-positive and Gram-negative bacteria.
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Affiliation(s)
- Andrea Brenciani
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche Medical School, Ancona, Italy
| | - Gianluca Morroni
- Unit of Microbiology, Department of Biomedical Sciences and Public Health, Polytechnic University of Marche Medical School, Ancona, Italy
| | - Stefan Schwarz
- Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany.,Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, People's Republic of China.,Veterinary Centre for Resistance Research (TZR), Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Eleonora Giovanetti
- Unit of Microbiology, Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
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10
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Mirzaei R, Alikhani MY, Arciola CR, Sedighi I, Irajian G, Jamasbi E, Yousefimashouf R, Bagheri KP. Highly Synergistic Effects of Melittin With Vancomycin and Rifampin Against Vancomycin and Rifampin Resistant Staphylococcus epidermidis. Front Microbiol 2022; 13:869650. [PMID: 35814659 PMCID: PMC9260053 DOI: 10.3389/fmicb.2022.869650] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 05/11/2022] [Indexed: 12/27/2022] Open
Abstract
Methicillin-resistant Staphylococcus epidermidis (MRSE) strains are increasingly emerging as serious pathogens because they can be resistant to many antibiotics called multidrug resistance (MDR) that limit the therapeutic options. In the case of vancomycin- and rifampin-resistant MDR-MRSE, the physicians are not allowed to increase the doses of antibiotics because of severe toxicity. Accordingly, we investigated the synergistic activity of melittin antimicrobial peptide with vancomycin and rifampin against vancomycin-resistant, and rifampin-resistant MDR-MRSE isolates. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), fractional inhibitory concentration index (FICi), and fractional bactericidal concentration index (FBCi) of antimicrobial agents against isolates were determined. Coagulate activities and serum and salt stability as well as melittin cytotoxicity on the human embryonic kidney (HEK) 293 cells and human red blood cells (RBCs) at their synergistic concentrations. MIC and MBC values for melittin were in the range of 0.312–2.5 and 0.312–5, respectively. Results also showed that the interaction of melittin with drugs was highly synergistic in which the geometric means of FICi and FBCi were < 0.5. Induced synergism led to a decrease in melittin, rifampin, and vancomycin concentrations by 8–1,020, 2–16, and 4–16-folds, respectively. This phenomenon caused a reduction in melittin toxicity by which the synergistic concentration of melittin needed to kill bacteria did not show cytotoxicity and hemolytic activity. Besides, no coagulation activity was found for the synergistic and alone concentrations of melittin in both Prothrombin Time (PT) and Partial Thromboplastin Time (PTT). Interestingly, the antibacterial activity of melittin in Mueller Hinton Broth (MHB) containing human serum did no significant differences between MIC and MBC values of melittin in MHB and MHB containing 10% human serum. The present findings showed that the therapeutic index of melittin was improved by 32.08- and 12.82-folds when combined with vancomycin and rifampin, respectively. Taken together, the obtained data show that melittin alone was effective against MDR-MRSE isolates and this antimicrobial peptide showed highly synergistic effects with vancomycin and rifampin without causing toxicity. Therefore, the combination of melittin and traditional antibiotics could be a promising strategy for the treatment of infections caused by MDR-MRSE.
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Affiliation(s)
- Rasoul Mirzaei
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
- Venom and Biotherapeutics Molecules Laboratory, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Mohammad Yousef Alikhani
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Carla Renata Arciola
- Laboratorio di Patologia delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
- Laboratorio di Immunoreumatologia e Rigenerazione Tissutale, IRCCS Istituto Ortopedico Rizzoli, Bologn, Italy
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Iraj Sedighi
- Department of Pediatrics, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - GholamReza Irajian
- Microbial Biotechnology Research Center, Iran University of Medical Sciences, Tehran, Iran
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Elaheh Jamasbi
- Research Center of Oils and Fats, Kermanshah University of Medical Science, Kermanshah, Iran
| | - Rasoul Yousefimashouf
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
- *Correspondence: Rasoul Yousefimashouf,
| | - Kamran Pooshang Bagheri
- Venom and Biotherapeutics Molecules Laboratory, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
- Kamran Pooshang Bagheri,
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11
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Müller A, Sakurai K, Seinige D, Nishino K, Kehrenberg C. Mutations in the Phenicol Exporter Gene fexA Impact Resistance Levels in Three Bacterial Hosts According to Susceptibility Testing and Protein Modeling. Front Microbiol 2022; 12:794435. [PMID: 35069492 PMCID: PMC8777102 DOI: 10.3389/fmicb.2021.794435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/14/2021] [Indexed: 11/13/2022] Open
Abstract
The prototype fexA gene confers combined resistance to chloramphenicol and florfenicol. However, fexA variants mediating resistance only to chloramphenicol have been identified, such as in the case of a Staphylococcus aureus isolate recovered from poultry meat illegally imported to Germany. The effects of the individual mutations detected in the fexA sequence of this isolate were investigated in this study. A total of 11 fexA variants, including prototype fexA and variants containing the different previously described mutations either alone or in different combinations, were generated by on-chip gene synthesis and site-directed mutagenesis. The constructs were inserted into a shuttle vector and transformed into three recipient strains (Escherichia coli, Staphylococcus aureus, and Salmonella Typhimurium). Subsequently, minimal inhibitory concentrations (MIC) of florfenicol and chloramphenicol were determined. In addition, protein modeling was used to predict the structural effects of the mutations. The lack of florfenicol-resistance mediating properties of the fexA variants could be attributed to the presence of a C110T and/or G98C mutation. Transformants carrying fexA variants containing either of these mutations, or both, showed a reduction of florfenicol MICs compared to those transformants carrying prototype fexA or any of the other variants. The significance of these mutations was supported by the generated protein models, indicating a substitution toward more voluminous amino-acids in the substrate-binding site of FexA. The remaining mutations, A391G and C961A, did not result in lower florfenicol-resistance compared to prototype fexA.
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Affiliation(s)
- Anja Müller
- Institute for Veterinary Food Science, Justus Liebig University Giessen, Giessen, Germany
| | - Keisuke Sakurai
- Institute for Protein Research, Osaka University, Osaka, Japan
| | - Diana Seinige
- Lower Saxony State Office for Consumer Protection and Food Safety, Wardenburg, Germany
| | - Kunihiko Nishino
- SANKEN, Institute of Scientific and Industrial Research, Osaka University, Osaka, Japan
| | - Corinna Kehrenberg
- Institute for Veterinary Food Science, Justus Liebig University Giessen, Giessen, Germany
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12
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OUP accepted manuscript. J Antimicrob Chemother 2022; 77:1838-1846. [DOI: 10.1093/jac/dkac119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 03/18/2022] [Indexed: 11/14/2022] Open
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13
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Papan C, Schröder M, Hoffmann M, Knoll H, Last K, Albrecht F, Geisel J, Fink T, Gärtner BC, Mellmann A, Volk T, Berger FK, Becker SL. Combined antibiotic stewardship and infection control measures to contain the spread of linezolid-resistant Staphylococcus epidermidis in an intensive care unit. Antimicrob Resist Infect Control 2021; 10:99. [PMID: 34193293 PMCID: PMC8242281 DOI: 10.1186/s13756-021-00970-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/13/2021] [Indexed: 11/24/2022] Open
Abstract
Background The unrestricted use of linezolid has been linked to the emergence of linezolid-resistant Staphylococcus epidermidis (LRSE). We report the effects of combined antibiotic stewardship and infection control measures on the spread of LRSE in an intensive care unit (ICU). Methods Microbiological data were reviewed to identify all LRSE detected in clinical samples at an ICU in southwest Germany. Quantitative data on the use of antibiotics with Gram-positive coverage were obtained in defined daily doses (DDD) per 100 patient-days (PD). In addition to infection control measures, an antibiotic stewardship intervention was started in May 2019, focusing on linezolid restriction and promoting vancomycin, wherever needed. We compared data from the pre-intervention period (May 2018–April 2019) to the post-intervention period (May 2019–April 2020). Whole-genome sequencing (WGS) was performed to determine the genetic relatedness of LRSE isolates. Results In the pre-intervention period, LRSE were isolated from 31 patients (17 in blood cultures). The average consumption of linezolid and daptomycin decreased from 7.5 DDD/100 PD and 12.3 DDD/100 PD per month in the pre-intervention period to 2.5 DDD/100 PD and 5.7 DDD/100 PD per month in the post-intervention period (p = 0.0022 and 0.0205), respectively. Conversely, vancomycin consumption increased from 0.2 DDD/100 PD per month to 4.7 DDD/100 PD per month (p < 0.0001). In the post-intervention period, LRSE were detected in 6 patients (4 in blood cultures) (p = 0.0065). WGS revealed the predominance of one single clone. Conclusions Complementing infection control measures by targeted antibiotic stewardship interventions was beneficial in containing the spread of LRSE in an ICU. Supplementary Information The online version contains supplementary material available at 10.1186/s13756-021-00970-3.
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Affiliation(s)
- Cihan Papan
- Center for Infectious Diseases, Institute of Medical Microbiology and Hygiene, Saarland University, Kirrberger Strasse, Building 43, 66421, Homburg, Germany.
| | - Matthias Schröder
- Department of Anesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center, Homburg, Germany
| | | | - Heike Knoll
- Department of Anesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center, Homburg, Germany
| | - Katharina Last
- Center for Infectious Diseases, Institute of Medical Microbiology and Hygiene, Saarland University, Kirrberger Strasse, Building 43, 66421, Homburg, Germany
| | - Frederic Albrecht
- Department of Anesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center, Homburg, Germany
| | - Jürgen Geisel
- Department of Clinical Chemistry and Laboratory Medicine, Saarland University, Homburg, Germany
| | - Tobias Fink
- Department of Anesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center, Homburg, Germany
| | - Barbara C Gärtner
- Center for Infectious Diseases, Institute of Medical Microbiology and Hygiene, Saarland University, Kirrberger Strasse, Building 43, 66421, Homburg, Germany
| | | | - Thomas Volk
- Department of Anesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center, Homburg, Germany
| | - Fabian K Berger
- Center for Infectious Diseases, Institute of Medical Microbiology and Hygiene, Saarland University, Kirrberger Strasse, Building 43, 66421, Homburg, Germany
| | - Sören L Becker
- Center for Infectious Diseases, Institute of Medical Microbiology and Hygiene, Saarland University, Kirrberger Strasse, Building 43, 66421, Homburg, Germany
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14
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Schwarz S, Zhang W, Du XD, Krüger H, Feßler AT, Ma S, Zhu Y, Wu C, Shen J, Wang Y. Mobile Oxazolidinone Resistance Genes in Gram-Positive and Gram-Negative Bacteria. Clin Microbiol Rev 2021; 34:e0018820. [PMID: 34076490 PMCID: PMC8262807 DOI: 10.1128/cmr.00188-20] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [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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Affiliation(s)
- Stefan Schwarz
- Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Wanjiang Zhang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
| | - Xiang-Dang Du
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People’s Republic of China
| | - Henrike Krüger
- Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Andrea T. Feßler
- Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Shizhen Ma
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Yao Zhu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, People’s Republic of China
| | - Congming Wu
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Jianzhong Shen
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
| | - Yang Wang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, People’s Republic of China
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15
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Huber S, Knoll MA, Berktold M, Würzner R, Brindlmayer A, Weber V, Posch AE, Mrazek K, Lepuschitz S, Ante M, Beisken S, Orth-Höller D, Weinberger J. Genomic and Phenotypic Analysis of Linezolid-Resistant Staphylococcus epidermidis in a Tertiary Hospital in Innsbruck, Austria. Microorganisms 2021; 9:1023. [PMID: 34068744 PMCID: PMC8150687 DOI: 10.3390/microorganisms9051023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 11/17/2022] Open
Abstract
Whole genome sequencing is a useful tool to monitor the spread of resistance mechanisms in bacteria. In this retrospective study, we investigated genetic resistance mechanisms, sequence types (ST) and respective phenotypes of linezolid-resistant Staphylococcus epidermidis (LRSE, n = 129) recovered from a cohort of patients receiving or not receiving linezolid within a tertiary hospital in Innsbruck, Austria. Hereby, the point mutation G2603U in the 23S rRNA (n = 91) was the major resistance mechanism followed by the presence of plasmid-derived cfr (n = 30). The majority of LRSE isolates were ST2 strains, followed by ST5. LRSE isolates expressed a high resistance level to linezolid with a minimal inhibitory concentration of ≥256 mg/L (n = 83) in most isolates, particularly in strains carrying the cfr gene (p < 0.001). Linezolid usage was the most prominent (but not the only) trigger for the development of linezolid resistance. However, administration of linezolid was not associated with a specific resistance mechanism. Restriction of linezolid usage and the monitoring of plasmid-derived cfr in LRSE are potential key steps to reduce linezolid resistance and its transmission to more pathogenic Gram-positive bacteria.
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Affiliation(s)
- Silke Huber
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (S.H.); (M.A.K.); (M.B.); (R.W.)
| | - Miriam A. Knoll
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (S.H.); (M.A.K.); (M.B.); (R.W.)
| | - Michael Berktold
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (S.H.); (M.A.K.); (M.B.); (R.W.)
| | - Reinhard Würzner
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (S.H.); (M.A.K.); (M.B.); (R.W.)
| | - Anita Brindlmayer
- Center for Biomedical Technology, Department for Biomedical Research, Danube University Krems, 3500 Krems, Austria; (A.B.); (V.W.)
| | - Viktoria Weber
- Center for Biomedical Technology, Department for Biomedical Research, Danube University Krems, 3500 Krems, Austria; (A.B.); (V.W.)
| | - Andreas E. Posch
- Ares Genetics GmbH, 1030 Vienna, Austria; (A.E.P.); (K.M.); (S.L.); (M.A.); (S.B.); (J.W.)
| | - Katharina Mrazek
- Ares Genetics GmbH, 1030 Vienna, Austria; (A.E.P.); (K.M.); (S.L.); (M.A.); (S.B.); (J.W.)
| | - Sarah Lepuschitz
- Ares Genetics GmbH, 1030 Vienna, Austria; (A.E.P.); (K.M.); (S.L.); (M.A.); (S.B.); (J.W.)
| | - Michael Ante
- Ares Genetics GmbH, 1030 Vienna, Austria; (A.E.P.); (K.M.); (S.L.); (M.A.); (S.B.); (J.W.)
| | - Stephan Beisken
- Ares Genetics GmbH, 1030 Vienna, Austria; (A.E.P.); (K.M.); (S.L.); (M.A.); (S.B.); (J.W.)
| | | | - Johannes Weinberger
- Ares Genetics GmbH, 1030 Vienna, Austria; (A.E.P.); (K.M.); (S.L.); (M.A.); (S.B.); (J.W.)
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16
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Turner AM, Lee JYH, Gorrie CL, Howden BP, Carter GP. Genomic Insights Into Last-Line Antimicrobial Resistance in Multidrug-Resistant Staphylococcus and Vancomycin-Resistant Enterococcus. Front Microbiol 2021; 12:637656. [PMID: 33796088 PMCID: PMC8007764 DOI: 10.3389/fmicb.2021.637656] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/25/2021] [Indexed: 12/17/2022] Open
Abstract
Multidrug-resistant Staphylococcus and vancomycin-resistant Enterococcus (VRE) are important human pathogens that are resistant to most clinical antibiotics. Treatment options are limited and often require the use of 'last-line' antimicrobials such as linezolid, daptomycin, and in the case of Staphylococcus, also vancomycin. The emergence of resistance to these last-line antimicrobial agents is therefore of considerable clinical concern. This mini-review provides an overview of resistance to last-line antimicrobial agents in Staphylococcus and VRE, with a particular focus on how genomics has provided critical insights into the emergence of resistant clones, the molecular mechanisms of resistance, and the importance of mobile genetic elements in the global spread of resistance to linezolid.
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Affiliation(s)
- Adrianna M Turner
- Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Jean Y H Lee
- Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia.,Department of Infectious Diseases, Monash Health, Melbourne, VIC, Australia
| | - Claire L Gorrie
- Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia.,Antimicrobial Reference and Research Unit, Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Benjamin P Howden
- Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia.,Antimicrobial Reference and Research Unit, Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia.,Department of Infectious Diseases, Austin Health, Melbourne, VIC, Australia
| | - Glen P Carter
- Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia.,Antimicrobial Reference and Research Unit, Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia
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17
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Cole K, Atkins B, Llewelyn M, Paul J. Genomic investigation of clinically significant coagulase-negative staphylococci. J Med Microbiol 2021; 70. [PMID: 33704043 DOI: 10.1099/jmm.0.001337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Introduction. Coagulase-negative staphylococci have been recognized both as emerging pathogens and contaminants of clinical samples. High-resolution genomic investigation may provide insights into their clinical significance.Aims. To review the literature regarding coagulase-negative staphylococcal infection and the utility of genomic methods to aid diagnosis and management, and to identify promising areas for future research.Methodology. We searched Google Scholar with the terms (Staphylococcus) AND (sequencing OR (infection)). We prioritized papers that addressed coagulase-negative staphylococci, genomic analysis, or infection.Results. A number of studies have investigated specimen-related, phenotypic and genetic factors associated with colonization, infection and virulence, but diagnosis remains problematic.Conclusion. Genomic investigation provides insights into the genetic diversity and natural history of colonization and infection. Such information allows the development of new methodologies to identify and compare relatedness and predict antimicrobial resistance. Future clinical studies that employ suitable sampling frames coupled with the application of high-resolution whole-genome sequencing may aid the development of more discriminatory diagnostic approaches to coagulase-staphylococcal infection.
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Affiliation(s)
- Kevin Cole
- Brighton and Sussex Medical School, Brighton, UK.,Public Health England Collaborating Centre, Royal Sussex County Hospital, Brighton, UK
| | | | - Martin Llewelyn
- Brighton and Sussex University Hospitals NHS Trust, Brighton, UK.,Brighton and Sussex Medical School, Brighton, UK
| | - John Paul
- Public Health England Collaborating Centre, Royal Sussex County Hospital, Brighton, UK.,Brighton and Sussex Medical School, Brighton, UK
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18
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Fioriti S, Morroni G, Coccitto SN, Brenciani A, Antonelli A, Di Pilato V, Baccani I, Pollini S, Cucco L, Morelli A, Paniccià M, Magistrali CF, Rossolini GM, Giovanetti E. Detection of Oxazolidinone Resistance Genes and Characterization of Genetic Environments in Enterococci of Swine Origin, Italy. Microorganisms 2020; 8:E2021. [PMID: 33348682 PMCID: PMC7766396 DOI: 10.3390/microorganisms8122021] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 11/16/2022] Open
Abstract
One hundred forty-five florfenicol-resistant enterococci, isolated from swine fecal samples collected from 76 pig farms, were investigated for the presence of optrA, cfr, and poxtA genes by PCR. Thirty florfenicol-resistant Enterococcus isolates had at least one linezolid resistance gene. optrA was found to be the most widespread linezolid resistance gene (23/30), while cfr and poxtA were detected in 6/30 and 7/30 enterococcal isolates, respectively. WGS analysis also showed the presence of the cfr(D) gene in Enterococcus faecalis (n = 2 isolates) and in Enterococcus avium (n = 1 isolate). The linezolid resistance genes hybridized both on chromosome and plasmids ranging from ~25 to ~240 kb. Twelve isolates were able to transfer linezolid resistance genes to enterococci recipient. WGS analysis displayed a great variability of optrA genetic contexts identical or related to transposons (Tn6628 and Tn6674), plasmids (pE035 and pWo27-9), and chromosomal regions. cfr environments showed identities with Tn6644-like transposon and a region from p12-2300 plasmid; cfr(D) genetic contexts were related to the corresponding region of the plasmid 4 of Enterococcus faecium E8014; poxtA was always found on Tn6657. Circular forms were obtained only for optrA- and poxtA-carrying genetic contexts. Clonality analysis revealed the presence of E. faecalis (ST16, ST27, ST476, and ST585) and E. faecium (ST21) clones previously isolated from humans. These results demonstrate a dissemination of linezolid resistance genes in enterococci of swine origin in Central Italy and confirm the spread of linezolid resistance in animal settings.
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Affiliation(s)
- Simona Fioriti
- Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, 60121 Ancona, Italy; (S.F.); (G.M.); (S.N.C.)
| | - Gianluca Morroni
- Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, 60121 Ancona, Italy; (S.F.); (G.M.); (S.N.C.)
| | - Sonia Nina Coccitto
- Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, 60121 Ancona, Italy; (S.F.); (G.M.); (S.N.C.)
| | - Andrea Brenciani
- Department of Biomedical Sciences and Public Health, Polytechnic University of Marche, 60121 Ancona, Italy; (S.F.); (G.M.); (S.N.C.)
| | - Alberto Antonelli
- Department of Experimental and Clinical Medicine, University of Florence, 50121 Florence, Italy; (A.A.); (I.B.); (S.P.); (G.M.R.)
- Clinical Microbiology and Virology Unit, Florence Careggi University Hospital, 50139 Florence, Italy
| | - Vincenzo Di Pilato
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, 16126 Genoa, Italy;
| | - Ilaria Baccani
- Department of Experimental and Clinical Medicine, University of Florence, 50121 Florence, Italy; (A.A.); (I.B.); (S.P.); (G.M.R.)
| | - Simona Pollini
- Department of Experimental and Clinical Medicine, University of Florence, 50121 Florence, Italy; (A.A.); (I.B.); (S.P.); (G.M.R.)
- Clinical Microbiology and Virology Unit, Florence Careggi University Hospital, 50139 Florence, Italy
| | - Lucilla Cucco
- Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche ‘Togo Rosati’, 06126 Perugia, Italy; (L.C.); (A.M.); (M.P.); (C.F.M.)
| | - Alessandra Morelli
- Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche ‘Togo Rosati’, 06126 Perugia, Italy; (L.C.); (A.M.); (M.P.); (C.F.M.)
| | - Marta Paniccià
- Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche ‘Togo Rosati’, 06126 Perugia, Italy; (L.C.); (A.M.); (M.P.); (C.F.M.)
| | - Chiara Francesca Magistrali
- Istituto Zooprofilattico Sperimentale dell’Umbria e delle Marche ‘Togo Rosati’, 06126 Perugia, Italy; (L.C.); (A.M.); (M.P.); (C.F.M.)
| | - Gian Maria Rossolini
- Department of Experimental and Clinical Medicine, University of Florence, 50121 Florence, Italy; (A.A.); (I.B.); (S.P.); (G.M.R.)
- Clinical Microbiology and Virology Unit, Florence Careggi University Hospital, 50139 Florence, Italy
| | - Eleonora Giovanetti
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60121 Ancona, Italy;
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19
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De Oliveira DMP, Forde BM, Kidd TJ, Harris PNA, Schembri MA, Beatson SA, Paterson DL, Walker MJ. Antimicrobial Resistance in ESKAPE Pathogens. Clin Microbiol Rev 2020; 23:788-99. [PMID: 32404435 DOI: 10.1111/imb.12124] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023] Open
Abstract
Antimicrobial-resistant ESKAPE ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens represent a global threat to human health. The acquisition of antimicrobial resistance genes by ESKAPE pathogens has reduced the treatment options for serious infections, increased the burden of disease, and increased death rates due to treatment failure and requires a coordinated global response for antimicrobial resistance surveillance. This looming health threat has restimulated interest in the development of new antimicrobial therapies, has demanded the need for better patient care, and has facilitated heightened governance over stewardship practices.
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Affiliation(s)
- David M P De Oliveira
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Brian M Forde
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Timothy J Kidd
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Patrick N A Harris
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
- UQ Centre for Clinical Research, The University of Queensland, QLD, Australia
| | - Mark A Schembri
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Scott A Beatson
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - David L Paterson
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
- UQ Centre for Clinical Research, The University of Queensland, QLD, Australia
| | - Mark J Walker
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
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20
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De Oliveira DMP, Forde BM, Kidd TJ, Harris PNA, Schembri MA, Beatson SA, Paterson DL, Walker MJ. Antimicrobial Resistance in ESKAPE Pathogens. Clin Microbiol Rev 2020; 33:e00181-19. [PMID: 32404435 PMCID: PMC7227449 DOI: 10.1128/cmr.00181-19] [Citation(s) in RCA: 836] [Impact Index Per Article: 209.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Antimicrobial-resistant ESKAPE ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens represent a global threat to human health. The acquisition of antimicrobial resistance genes by ESKAPE pathogens has reduced the treatment options for serious infections, increased the burden of disease, and increased death rates due to treatment failure and requires a coordinated global response for antimicrobial resistance surveillance. This looming health threat has restimulated interest in the development of new antimicrobial therapies, has demanded the need for better patient care, and has facilitated heightened governance over stewardship practices.
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Affiliation(s)
- David M P De Oliveira
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Brian M Forde
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Timothy J Kidd
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Patrick N A Harris
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
- UQ Centre for Clinical Research, The University of Queensland, QLD, Australia
| | - Mark A Schembri
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - Scott A Beatson
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
| | - David L Paterson
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
- UQ Centre for Clinical Research, The University of Queensland, QLD, Australia
| | - Mark J Walker
- School of Chemistry and Molecular Biosciences, The University of Queensland, QLD, Australia
- Australian Infectious Diseases Research Centre, The University of Queensland, QLD, Australia
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21
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Kosecka-Strojek M, Sadowy E, Gawryszewska I, Klepacka J, Tomasik T, Michalik M, Hryniewicz W, Miedzobrodzki J. Emergence of linezolid-resistant Staphylococcus epidermidis in the tertiary children's hospital in Cracow, Poland. Eur J Clin Microbiol Infect Dis 2020; 39:1717-1725. [PMID: 32350737 PMCID: PMC7427702 DOI: 10.1007/s10096-020-03893-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 04/01/2020] [Indexed: 11/26/2022]
Abstract
Coagulase-negative staphylococci, ubiquitous commensals of human skin, and mucous membranes represent important pathogens for immunocompromised patients and neonates. The increasing antibiotic resistance among Staphylococcus epidermidis is an emerging problem worldwide. In particular, the linezolid-resistant S. epidermidis (LRSE) strains are observed in Europe since 2014. The aim of our study was to genetically characterize 11 LRSE isolates, recovered mostly from blood in the University Children’s Hospital in Krakow, Poland, between 2015 and 2017. For identification of the isolates at the species level, we used 16S rRNA sequencing and RFLP of the saoC gene. Isolates were characterized phenotypically by determining their antimicrobial resistance patterns and using molecular methods such as PFGE, MLST, SCCmec typing, detection of the ica operon, and analysis of antimicrobial resistance determinants. All isolates were multidrug-resistant, including resistance to methicillin, and exhibited so-called PhLOPSA phenotype. In PFGE, all isolates (excluding one from a catheter) represented identical patterns, were identified as ST2, and harbored the ica operon, responsible for biofilm formation. Linezolid resistance was associated with acquisition of A157R mutation in the ribosomal protein L3 and the presence of cfr gene. All isolates revealed new SCCmec cassette element composition. Recently, pediatric patients with serious staphylococcal infections are often treated with linezolid. The increasing linezolid resistance in bacterial strains becomes a real threat for patients, and monitoring such infections combined with surveillance and infection prevention programs is very important to decrease number of linezolid-resistant staphylococcal strains.
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Affiliation(s)
- Maja Kosecka-Strojek
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Krakow, Poland
| | - Ewa Sadowy
- Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland
| | - Iwona Gawryszewska
- Department of Molecular Microbiology, National Medicines Institute, Warsaw, Poland
| | - Joanna Klepacka
- Department of Clinical Microbiology, Children's University Hospital, Jagiellonian University, Krakow, Poland
| | - Tomasz Tomasik
- Department of Clinical Microbiology, Children's University Hospital, Jagiellonian University, Krakow, Poland
| | | | - Waleria Hryniewicz
- Department of Epidemiology and Clinical Microbiology, National Medicines Institute, Warsaw, Poland
| | - Jacek Miedzobrodzki
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387, Krakow, Poland.
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22
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Werner G, Fleige C, Klare I, Weber RE, Bender JK. Validating a screening agar for linezolid-resistant enterococci. BMC Infect Dis 2019; 19:1078. [PMID: 31870418 PMCID: PMC6929501 DOI: 10.1186/s12879-019-4711-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/17/2019] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Linezolid is an alternative treatment option for infections with multidrug-resistant Gram-positive bacteria including vancomycin-resistant enterococci. Some countries report an increasing number of isolates with resistance to linezolid. The recent publication of the Commission for Hospital Hygiene in Germany on enterococci/VRE recommends screening for linezolid-resistant enterococci (LRE). However, a suitable selective medium or a genetic test is not available. Our aim was to establish a selective screening agar for LRE detection and validate its application with a comprehensive collection of clinical LRE and linezolid-susceptible enterococci. METHODS We decided to combine the selective power of an enterococcal screening agar with a supplementation of linezolid. Several rounds of analyses with reference, control and test strains and under varying linezolid concentrations of a wider and a smaller range were investigated and assessed. The collection of linezolid-resistant enterococcal control strains included isolates with different resistance mechanisms (23S rDNA mutations, cfr(B), optrA, poxtA). Finally, we validated our LRE screening agar with 400 samples sent to our National Reference Centre in 2019. RESULTS Several rounds of pre-tests and confirmatory analyses favored Enterococcosel® Agar supplemented with a concentration of 2 mg/L linezolid. A 48 h incubation period was essential for accurate identification of LRE strains. Performance of the LRE screening agar revealed a sensitivity of 96.6% and a specificity of 94.4%. CONCLUSIONS Here we describe preparation of a suitable screening agar and a procedure to identify LRE isolates with high accuracy.
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Affiliation(s)
- Guido Werner
- Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany.
| | - Carola Fleige
- Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Ingo Klare
- Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Robert E Weber
- Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Jennifer K Bender
- Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, National Reference Centre for Staphylococci and Enterococci (NRC), Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
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23
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Kramer TS, Schwab F, Behnke M, Hansen S, Gastmeier P, Aghdassi SJS. Linezolid use in German acute care hospitals: results from two consecutive national point prevalence surveys. Antimicrob Resist Infect Control 2019; 8:159. [PMID: 31649816 PMCID: PMC6805522 DOI: 10.1186/s13756-019-0617-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 10/01/2019] [Indexed: 12/12/2022] Open
Abstract
Background Linezolid belongs to a reserve group of antibiotics. In recent years, reports on linezolid resistance in gram-positive cocci have become more frequent. Overuse of linezolid is a relevant factor for resistance development. The objective of this study was to describe current prescription practices of linezolid in German hospitals and identify targets for antimicrobial stewardship interventions. Methods We analyzed all linezolid prescriptions from the datasets of the consecutive national point prevalence surveys performed in German hospitals in 2011 and 2016. In both surveys, data on healthcare-associated infections and antimicrobial use were collected following the methodology of the European Centre for Disease Prevention and Control. Results Overall, the percentage of linezolid among all documented antimicrobials increased significantly from 2011 to 2016 (p < 0.01). In 2011, 0.3% (119 of 41,539) patients received linezolid, in 2016 this proportion was significantly higher (0.4%; 255 of 64,412 patients; p < 0.01). In 2016, intensive care units (ICUs) were the wards most frequently prescribing linezolid. The largest proportion of patients receiving linezolid were non-ICU patients. Roughly 38% of linezolid prescriptions were for treatment of skin/soft tissue and respiratory tract infections. In 2016, linezolid was administered parenterally in 70% (n = 179) of cases. Multivariable analysis showed that the ward specialty ICU posed an independent risk factor, while Northern and Southwestern regions in Germany were independent protective factors for a high rate of linezolid prescriptions. Conclusions In conclusion, we detected potentials for improving linezolid prescription practices in German hospitals. Given the emergence of linezolid resistance, optimization of linezolid use must be a target of future antimicrobial stewardship activities.
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Affiliation(s)
- Tobias Siegfried Kramer
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Hygiene and Environmental Medicine, Berlin, Germany.,National Reference Center for Surveillance of Nosocomial Infections, Berlin, Germany
| | - Frank Schwab
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Hygiene and Environmental Medicine, Berlin, Germany.,National Reference Center for Surveillance of Nosocomial Infections, Berlin, Germany
| | - Michael Behnke
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Hygiene and Environmental Medicine, Berlin, Germany.,National Reference Center for Surveillance of Nosocomial Infections, Berlin, Germany
| | - Sonja Hansen
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Hygiene and Environmental Medicine, Berlin, Germany.,National Reference Center for Surveillance of Nosocomial Infections, Berlin, Germany
| | - Petra Gastmeier
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Hygiene and Environmental Medicine, Berlin, Germany.,National Reference Center for Surveillance of Nosocomial Infections, Berlin, Germany
| | - Seven Johannes Sam Aghdassi
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Hygiene and Environmental Medicine, Berlin, Germany.,National Reference Center for Surveillance of Nosocomial Infections, Berlin, Germany
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24
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Deshpande LM, Castanheira M, Flamm RK, Mendes RE. Evolving oxazolidinone resistance mechanisms in a worldwide collection of enterococcal clinical isolates: results from the SENTRY Antimicrobial Surveillance Program. J Antimicrob Chemother 2019; 73:2314-2322. [PMID: 29878213 DOI: 10.1093/jac/dky188] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 04/18/2018] [Indexed: 01/28/2023] Open
Abstract
Objectives This study evaluated the oxazolidinone resistance mechanisms among a global collection of enterococcal clinical isolates. The epidemiology of optrA-carrying isolates and the optrA genetic context were determined. Methods Enterococcal isolates (26 648) from the SENTRY Antimicrobial Surveillance Program (2008-16) were identified by MALDI-TOF MS and MICs were determined by broth microdilution. Isolates with linezolid MICs of ≥4 mg/L were screened for resistance mechanisms. Isolates carrying optrA had their genome sequenced for genetic context and epidemiology information. Results Thirty-six Enterococcus faecalis and 66 Enterococcus faecium had linezolid MICs of ≥4 mg/L (0.38% of surveillance enterococci). E. faecalis had a linezolid MIC range of 4-16 mg/L, while E. faecium displayed higher values (4-64 mg/L). Nine E. faecalis had G2576T mutations and optrA was detected in 26 (72.2%) isolates from the Asia-Pacific region, North America, Latin America and Europe; 3 isolates also produced Cfr [Thailand (1)] or Cfr(B) [Panama (2)]. All E. faecium isolates had G2576T alterations, while three isolates from the USA had concomitant presence of cfr(B). The optrA gene was plasmid- and chromosome-located in 22 and 3 E. faecalis, respectively. One isolate signalled hybridization on plasmid and chromosome. The genetic context of optrA varied. E. faecalis belonging to the same clonal complex were detected in distinct geographical regions. Also, genetically distinct isolates from Ireland had an identical optrA context, indicating plasmid dissemination. Conclusions Alterations in 23S rRNA remained the main oxazolidinone resistance mechanism in E. faecium, while optrA prevailed in E. faecalis. These results demonstrate global dissemination of optrA and warrant surveillance for monitoring.
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Affiliation(s)
| | | | - R K Flamm
- JMI Laboratories, North Liberty, IA, USA
| | - R E Mendes
- JMI Laboratories, North Liberty, IA, USA
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25
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Weßels C, Strommenger B, Klare I, Bender J, Messler S, Mattner F, Krakau M, Werner G, Layer F. Emergence and control of linezolid-resistant Staphylococcus epidermidis in an ICU of a German hospital. J Antimicrob Chemother 2019; 73:1185-1193. [PMID: 29438544 DOI: 10.1093/jac/dky010] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/02/2018] [Indexed: 11/13/2022] Open
Abstract
Objectives To investigate an outbreak of linezolid-resistant Staphylococcus epidermidis (LRSE) in an interdisciplinary ICU, linezolid consumption and infection control measures taken. Methods Routine surveillance of nosocomial infections revealed colonization and infection with LRSE affecting 14 patients during a 15 month period. LRSE isolates were analysed with respect to their clonal relatedness, antimicrobial susceptibility, the presence of cfr and/or mutations in the 23S rRNA, rplC, rplD and rplV genes. cfr plasmids were characterized by Illumina sequencing. Medical records were reviewed and antibiotic consumption was determined. Results Molecular typing identified the presence of three different LRSE clusters: PFGE type I/ST168 (n = 5), PFGE type II/ST5 (n = 10) and PFGE type III/ST2 (n = 1). Ten strains harboured the cfr gene; we also detected mutations in the respective ribosomal protein genes. WGS revealed an almost identical 39 kb cfr plasmid obtained from strains of different genetic background (ST2, ST5, ST168) that shows high similarity to the recently published LRSE plasmid p12-02300. Due to an increase in the number of patients treated for infections with MRSA, a significant increase in linezolid usage was noted from January to July 2014 (from 5.55 to 20.41 DDDs/100 patient-days). Conclusions Here, we report the molecular epidemiology of LRSE in an ICU. Our results suggest the selection of resistant mutants under linezolid treatment as well as the spread of cfr-carrying plasmids. The reduction of linezolid usage and the strengthening of contact precautions proved to be effective infection control measures.
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Affiliation(s)
- Christina Weßels
- Institute of Hospital Hygiene, City of Cologne Hospitals, Cologne, Germany
| | - Birgit Strommenger
- National Reference Centre for Staphylococci and Enterococci, Division 13: Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Ingo Klare
- National Reference Centre for Staphylococci and Enterococci, Division 13: Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Jennifer Bender
- National Reference Centre for Staphylococci and Enterococci, Division 13: Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Sabine Messler
- Labor im Sommershof, Praxis für Laboratoriumsmedizin Dr. med. Christiane Boogen, Cologne, Germany
| | - Frauke Mattner
- Institute of Hospital Hygiene, City of Cologne Hospitals, Cologne, Germany
| | - Michael Krakau
- Department of Internal Medicine, City of Cologne Hospitals, Cologne, Germany
| | - Guido Werner
- National Reference Centre for Staphylococci and Enterococci, Division 13: Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Franziska Layer
- National Reference Centre for Staphylococci and Enterococci, Division 13: Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
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26
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Sun C, Zhang P, Ji X, Fan R, Chen B, Wang Y, Schwarz S, Wu C. Presence and molecular characteristics of oxazolidinone resistance in staphylococci from household animals in rural China. J Antimicrob Chemother 2019; 73:1194-1200. [PMID: 29425282 DOI: 10.1093/jac/dky009] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 01/02/2018] [Indexed: 12/18/2022] Open
Abstract
Objectives To investigate the presence and molecular characteristics of oxazolidinone resistance genes cfr and optrA in staphylococci from household animals in rural China. Methods Various samples were collected from household animals in 12 rural villages. Staphylococcal isolates showing florfenicol MICs ≥10 mg/L were identified and screened for the presence of cfr and/or optrA. PCR-positive isolates were characterized by antimicrobial susceptibility testing, S1 nuclease PFGE and Southern blotting. WGS data were analysed to identify the core-genome phylogenetic profile of each isolate as well as the genetic environment of cfr and/or optrA. Results Nine optrA-positive (seven Staphylococcus sciuri and two Staphylococcus simulans) and 10 cfr-positive staphylococci were identified from eight and five villages, respectively. The gene optrA was chromosomally encoded in all nine isolates, whereas cfr was located on a plasmid in one S. sciuri and three Staphylococcus saprophyticus and in the chromosomal DNA of single Staphylococcus cohnii and Staphylococcus lentus isolates and two S. sciuri isolates. The remaining two cfr-carrying Staphylococcus haemolyticus isolates were indistinguishable by PFGE. Most optrA- or cfr-carrying staphylococci also harboured phenicol, tetracycline and/or macrolide-lincosamide-streptogramin B resistance genes. Genetic environment analysis showed that, for the first time, optrA was associated with transposon Tn6261, while cfr was adjacent to both a tnp (transposase) gene and a Tn558 transposon. Conclusions The current study reveals for the first time the wide distribution of oxazolidinone resistance genes optrA and cfr in household animals in rural areas of China and is the first identification of optrA in S. simulans isolates.
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Affiliation(s)
- Chengtao Sun
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Peng Zhang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xing Ji
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Run Fan
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Baoli Chen
- Shandong Provincial Key Laboratory of Infectious Disease Control and Prevention, Shandong Centre for Disease Control and Prevention, Jinan, Shandong, China
| | - Yang Wang
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Stefan Schwarz
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China.,Institute of Microbiology and Epizootics, Centre for Infection Medicine, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Congming Wu
- Beijing Advanced Innovation Centre for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China
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27
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Layer F, Vourli S, Karavasilis V, Strommenger B, Dafopoulou K, Tsakris A, Werner G, Pournaras S. Dissemination of linezolid-dependent, linezolid-resistant Staphylococcus epidermidis clinical isolates belonging to CC5 in German hospitals. J Antimicrob Chemother 2019; 73:1181-1184. [PMID: 29360979 DOI: 10.1093/jac/dkx524] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/14/2017] [Indexed: 11/13/2022] Open
Abstract
Objectives Linezolid-resistant Staphylococcus epidermidis (LRSE) and linezolid-dependent ST22 strains have been shown to predominate in tertiary care facilities all over Greece. We report herein the dissemination of ST22 but also ST2, ST5 and ST168 linezolid-dependent LRSE clones in four unrelated German hospitals. Methods Fourteen LRSE clinical isolates recovered during 2012-14 from five distantly located German hospitals were tested by for MIC determination broth microdilution and Etest, PCR/sequencing for cfr and for mutations in 23S rRNA, rplC, rplD and rplV genes, MLST, PFGE and growth curves without and with linezolid at 16 and 32 mg/L. Results Most (11, 78.6%) isolates had linezolid MICs >256 mg/L. Five isolates carried the cfr gene. Eight isolates belonged to ST22, two isolates each to ST168 and ST2 and one isolate each to ST5 and ST23. Ten isolates [seven belonging to ST22 and one to each of ST2, ST5 and ST168; all these STs belong to clonal complex (CC) 5] exhibited linezolid-dependent growth, growing significantly faster in linezolid-containing broth. Four isolates were non-dependent (one belonging to each of ST22, ST2, ST23 and ST168). Four isolates came from three different hospitals, whereas four and six isolates were recovered during outbreaks of LRSE in two distinct hospitals. Conclusions The multi-clonal dissemination of CC5 linezolid-dependent LRSE throughout German hospitals along with the clonal expansion of ST22 linezolid-dependent LRSE in Greek hospitals is of particular concern. It is plausible that this characteristic is inherent and provides a selective advantage to CC5 LRSE under linezolid pressure, contributing to their dissemination throughout hospitals in these countries.
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Affiliation(s)
- Franziska Layer
- Robert Koch Institute, Department of Infectious Diseases, National Centre for Staphylococci and Enterococci, Wernigerode, Germany
| | - Sophia Vourli
- Laboratory of Clinical Microbiology, ATTIKON University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | | | - Birgit Strommenger
- Robert Koch Institute, Department of Infectious Diseases, National Centre for Staphylococci and Enterococci, Wernigerode, Germany
| | - Konstantina Dafopoulou
- Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Athanassios Tsakris
- Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Guido Werner
- Robert Koch Institute, Department of Infectious Diseases, National Centre for Staphylococci and Enterococci, Wernigerode, Germany
| | - Spyros Pournaras
- Laboratory of Clinical Microbiology, ATTIKON University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece.,Department of Microbiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
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28
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Bender JK, Fleige C, Klare I, Werner G. Development of a multiplex-PCR to simultaneously detect acquired linezolid resistance genes cfr, optrA and poxtA in enterococci of clinical origin. J Microbiol Methods 2019; 160:101-103. [PMID: 30940534 DOI: 10.1016/j.mimet.2019.03.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/27/2019] [Accepted: 03/29/2019] [Indexed: 10/27/2022]
Abstract
Linezolid-resistant enterococcus spp. are increasingly recognized by diagnostic laboratories. Resistance can be mediated by the expression of cfr, optrA or poxtA. We developed a multiplex-PCR to simultaneously detect all three genes. The PCR is suitable for microbiological diagnostics in order to restrict further spread of resistances in enterococci.
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Affiliation(s)
- Jennifer K Bender
- National Reference Centre for Staphylococci and Enterococci, Division of Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode, Germany.
| | - Carola Fleige
- National Reference Centre for Staphylococci and Enterococci, Division of Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode, Germany
| | - Ingo Klare
- National Reference Centre for Staphylococci and Enterococci, Division of Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode, Germany
| | - Guido Werner
- National Reference Centre for Staphylococci and Enterococci, Division of Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode, Germany
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29
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Abstract
Strains of Staphylococcus aureus, and to a lesser extent other staphylococcal species, are a significant cause of morbidity and mortality. An important factor in the notoriety of these organisms stems from their frequent resistance to many antimicrobial agents used for chemotherapy. This review catalogues the variety of mobile genetic elements that have been identified in staphylococci, with a primary focus on those associated with the recruitment and spread of antimicrobial resistance genes. These include plasmids, transposable elements such as insertion sequences and transposons, and integrative elements including ICE and SCC elements. In concert, these diverse entities facilitate the intra- and inter-cellular gene mobility that enables horizontal genetic exchange, and have also been found to play additional roles in modulating gene expression and genome rearrangement.
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30
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Lee JYH, Monk IR, Gonçalves da Silva A, Seemann T, Chua KYL, Kearns A, Hill R, Woodford N, Bartels MD, Strommenger B, Laurent F, Dodémont M, Deplano A, Patel R, Larsen AR, Korman TM, Stinear TP, Howden BP. Global spread of three multidrug-resistant lineages of Staphylococcus epidermidis. Nat Microbiol 2018; 3:1175-1185. [PMID: 30177740 PMCID: PMC6660648 DOI: 10.1038/s41564-018-0230-7] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 07/27/2018] [Indexed: 01/19/2023]
Abstract
Staphylococcus epidermidis is a conspicuous member of the human microbiome, widely present on healthy skin. Here we show that S. epidermidis has also evolved to become a formidable nosocomial pathogen. Using genomics, we reveal that three multidrug-resistant, hospital-adapted lineages of S. epidermidis (two ST2 and one ST23) have emerged in recent decades and spread globally. These lineages are resistant to rifampicin through acquisition of specific rpoB mutations that have become fixed in the populations. Analysis of isolates from 96 institutions in 24 countries identified dual D471E and I527M RpoB substitutions to be the most common cause of rifampicin resistance in S. epidermidis, accounting for 86.6% of mutations. Furthermore, we reveal that the D471E and I527M combination occurs almost exclusively in isolates from the ST2 and ST23 lineages. By breaching lineage-specific DNA methylation restriction modification barriers and then performing site-specific mutagenesis, we show that these rpoB mutations not only confer rifampicin resistance, but also reduce susceptibility to the last-line glycopeptide antibiotics, vancomycin and teicoplanin. Our study has uncovered the previously unrecognized international spread of a near pan-drug-resistant opportunistic pathogen, identifiable by a rifampicin-resistant phenotype. It is possible that hospital practices, such as antibiotic monotherapy utilizing rifampicin-impregnated medical devices, have driven the evolution of this organism, once trivialized as a contaminant, towards potentially incurable infections.
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Affiliation(s)
- Jean Y H Lee
- Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Ian R Monk
- Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Anders Gonçalves da Silva
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Torsten Seemann
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
- Melbourne Bioinformatics, The University of Melbourne, Melbourne, Australia
| | - Kyra Y L Chua
- Department of Microbiology, Austin Health, Melbourne, Australia
| | - Angela Kearns
- AMRHAI Reference Unit, National Infection Service, Public Health England, London, UK
| | - Robert Hill
- AMRHAI Reference Unit, National Infection Service, Public Health England, London, UK
| | - Neil Woodford
- AMRHAI Reference Unit, National Infection Service, Public Health England, London, UK
| | - Mette D Bartels
- Department of Clinical Microbiology, Hvidovre University Hospital, Hvidovre, Denmark
| | - Birgit Strommenger
- National Reference Centre for Staphylococci and Enterococci, Division Nosocomial Pathogens and Antibiotic Resistances, Department of Infectious Diseases, Robert Koch Institute, Wernigerode Branch, Wernigerode, Germany
| | - Frederic Laurent
- Department of Bacteriology, Institute for Infectious Agents, French National Reference Centre for Staphylococci, International Centre for Infectiology Research, Institute for Pharmaceutical and Biological Sciences Of Lyon, University of Lyon, Lyon, France
| | - Magali Dodémont
- National Reference Centre for Staphylococci, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Ariane Deplano
- National Reference Centre for Staphylococci, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Robin Patel
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, and Division of Infectious Diseases, Department of Medicine, Mayo Clinic, Rochester, USA
| | - Anders R Larsen
- Reference Laboratory for Antimicrobial Resistance and Staphylococci, Statens Serum Institut, Copenhagen, Denmark
| | - Tony M Korman
- Monash Infectious Diseases, Centre for Inflammatory Diseases, Monash University, Melbourne, Australia
| | - Timothy P Stinear
- Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia
| | - Benjamin P Howden
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia.
- Doherty Applied Microbial Genomics, Department of Microbiology and Immunology, The University of Melbourne at The Doherty Institute for Infection and Immunity, Melbourne, Australia.
- Infectious Diseases Department, Austin Health, Melbourne, Australia.
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31
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Partridge SR, Kwong SM, Firth N, Jensen SO. Mobile Genetic Elements Associated with Antimicrobial Resistance. Clin Microbiol Rev 2018; 31:e00088-17. [PMID: 30068738 PMCID: PMC6148190 DOI: 10.1128/cmr.00088-17] [Citation(s) in RCA: 1162] [Impact Index Per Article: 193.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Strains of bacteria resistant to antibiotics, particularly those that are multiresistant, are an increasing major health care problem around the world. It is now abundantly clear that both Gram-negative and Gram-positive bacteria are able to meet the evolutionary challenge of combating antimicrobial chemotherapy, often by acquiring preexisting resistance determinants from the bacterial gene pool. This is achieved through the concerted activities of mobile genetic elements able to move within or between DNA molecules, which include insertion sequences, transposons, and gene cassettes/integrons, and those that are able to transfer between bacterial cells, such as plasmids and integrative conjugative elements. Together these elements play a central role in facilitating horizontal genetic exchange and therefore promote the acquisition and spread of resistance genes. This review aims to outline the characteristics of the major types of mobile genetic elements involved in acquisition and spread of antibiotic resistance in both Gram-negative and Gram-positive bacteria, focusing on the so-called ESKAPEE group of organisms (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp., and Escherichia coli), which have become the most problematic hospital pathogens.
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Affiliation(s)
- Sally R Partridge
- Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, The University of Sydney and Westmead Hospital, Westmead, New South Wales, Australia
| | - Stephen M Kwong
- School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Neville Firth
- School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Slade O Jensen
- Microbiology and Infectious Diseases, School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- Antibiotic Resistance & Mobile Elements Group, Ingham Institute for Applied Medical Research, Sydney, New South Wales, Australia
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32
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Hygienemaßnahmen zur Prävention der Infektion durch Enterokokken mit speziellen Antibiotikaresistenzen. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2018; 61:1310-1361. [DOI: 10.1007/s00103-018-2811-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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33
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Feßler AT, Wang Y, Wu C, Schwarz S. Mobile lincosamide resistance genes in staphylococci. Plasmid 2018; 99:22-31. [DOI: 10.1016/j.plasmid.2018.06.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 06/16/2018] [Accepted: 06/18/2018] [Indexed: 01/31/2023]
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34
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Nguyen L, Román F, Morikawa K, Trincado P, Marcos C, Rojo-Martín M, Cafini F. Prevalence of pSCFS7-like vectors among cfr-positive staphylococcal population in Spain. Int J Antimicrob Agents 2018; 52:305-306. [DOI: 10.1016/j.ijantimicag.2018.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 04/20/2018] [Accepted: 06/02/2018] [Indexed: 11/29/2022]
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35
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Dortet L, Glaser P, Kassis-Chikhani N, Girlich D, Ichai P, Boudon M, Samuel D, Creton E, Imanci D, Bonnin R, Fortineau N, Naas T. Long-lasting successful dissemination of resistance to oxazolidinones in MDR Staphylococcus epidermidis clinical isolates in a tertiary care hospital in France. J Antimicrob Chemother 2018; 73:41-51. [PMID: 29092052 PMCID: PMC5890688 DOI: 10.1093/jac/dkx370] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 09/10/2017] [Indexed: 01/16/2023] Open
Abstract
Objectives Patient- and procedure-related changes in modern medicine have turned CoNS into one of the major nosocomial pathogens. Treatments of CoNS infections are challenging owing to the large proportion of MDR strains and oxazolidinones often remain the last active antimicrobial molecules. Here, we have investigated a long-lasting outbreak (2010-13) due to methicillin- and linezolid-resistant (LR) CoNS (n = 168), involving 72 carriers and 49 infected patients. Methods Antimicrobial susceptibilities were tested by the disc diffusion method and MICs were determined by broth microdilution or Etest. The clonal relationship of LR Staphylococcus epidermidis (LRSE) was first determined using a semi-automated repetitive element palindromic PCR (rep-PCR) method. Then, WGS was performed on all cfr-positive LRSE (n = 30) and LRSE isolates representative of each rep-PCR-defined clone (n = 17). Self-transferability of cfr-carrying plasmids was analysed by filter-mating experiments. Results This outbreak was caused by the dissemination of three clones (ST2, ST5 and ST22) of LRSE. In these clones, linezolid resistance was caused by (i) mutations in the chromosome-located genes encoding the 23S RNA and L3 and L4 ribosomal proteins, but also by (ii) the dissemination of two different self-conjugative plasmids carrying the cfr gene encoding a 23S RNA methylase. By monitoring linezolid prescriptions in two neighbouring hospitals, we highlighted that the spread of LR-CoNS was strongly associated with linezolid use. Conclusions Physicians should be aware that plasmid-encoded linezolid resistance has started to disseminate among CoNS and that rational use of oxazolidinones is critical to preserve these molecules as efficient treatment options for MDR Gram-positive pathogens.
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Affiliation(s)
- Laurent Dortet
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique - Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Philippe Glaser
- Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France.,UMR 3525, CNRS, 75015 Paris, France
| | - Najiby Kassis-Chikhani
- Department of Hygiene, Paul Brousse Hospital, Assistance Publique - Hôpitaux de Paris, Villejuif, France
| | - Delphine Girlich
- EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Philippe Ichai
- Intensive Care Unit, Hepatobiliary Center, Paul Brousse Hospital, Assistance Publique - Hôpitaux de Paris, Villejuif, France
| | - Marc Boudon
- Intensive Care Unit, Hepatobiliary Center, Paul Brousse Hospital, Assistance Publique - Hôpitaux de Paris, Villejuif, France
| | - Didier Samuel
- Intensive Care Unit, Hepatobiliary Center, Paul Brousse Hospital, Assistance Publique - Hôpitaux de Paris, Villejuif, France
| | - Elodie Creton
- EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Dilek Imanci
- Department of Molecular Genetics and Hormonology, Assistance Publique/Hôpitaux de Paris, Bicêtre Hospital, Le Kremlin-Bicêtre, France
| | - Rémy Bonnin
- EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Nicolas Fortineau
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique - Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France
| | - Thierry Naas
- Department of Bacteriology-Parasitology-Hygiene, Bicêtre Hospital, Assistance Publique - Hôpitaux de Paris, Le Kremlin-Bicêtre, France.,EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France.,Associated French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France.,Joint Research Unit EERA 'Evolution and Ecology of Resistance to Antibiotics', Institut Pasteur-APHP-University Paris Sud, Paris, France
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36
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Li X, Arias CA, Aitken SL, Galloway Peña J, Panesso D, Chang M, Diaz L, Rios R, Numan Y, Ghaoui S, DebRoy S, Bhatti MM, Simmons DE, Raad I, Hachem R, Folan SA, Sahasarabhojane P, Kalia A, Shelburne SA. Clonal Emergence of Invasive Multidrug-Resistant Staphylococcus epidermidis Deconvoluted via a Combination of Whole-Genome Sequencing and Microbiome Analyses. Clin Infect Dis 2018; 67:398-406. [PMID: 29546356 PMCID: PMC6051468 DOI: 10.1093/cid/ciy089] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 02/03/2018] [Indexed: 01/05/2023] Open
Abstract
Background Pathobionts, bacteria that are typically human commensals but can cause disease, contribute significantly to antimicrobial resistance. Staphylococcus epidermidis is a prototypical pathobiont as it is a ubiquitous human commensal but also a leading cause of healthcare-associated bacteremia. We sought to determine the etiology of a recent increase in invasive S. epidermidis isolates resistant to linezolid. Methods Whole-genome sequencing (WGS) was performed on 176 S. epidermidis bloodstream isolates collected at the MD Anderson Cancer Center in Houston, Texas, between 2013 and 2016. Molecular relationships were assessed via complementary phylogenomic approaches. Abundance of the linezolid resistance determinant cfr was determined in stool samples via reverse-transcription quantitative polymerase chain reaction. Results Thirty-nine of the 176 strains were linezolid resistant (22%). Thirty-one of the 39 linezolid-resistant S. epidermidis infections were caused by a particular clone resistant to multiple antimicrobials that spread among leukemia patients and carried cfr on a 49-kb plasmid (herein called pMB151a). The 6 kb of pMB151a surrounding the cfr gene was nearly 100% identical to a cfr-containing plasmid isolated from livestock-associated staphylococci in China. Analysis of serial stool samples from leukemia patients revealed progressive staphylococcal domination of the intestinal microflora and an increase in cfr abundance following linezolid use. Conclusions The combination of linezolid use plus transmission of a multidrug-resistant clone drove expansion of invasive, linezolid-resistant S. epidermidis. Our results lend support to the notion that a combination of antibiotic stewardship plus infection control measures may help to control the spread of a multidrug-resistant pathobiont.
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Affiliation(s)
- Xiqi Li
- Graduate Program in Diagnostic Genetics, School of Health Professions, University of Texas MD Anderson Cancer Center, Bogota, Colombia
| | - Cesar A Arias
- Center for Antimicrobial Resistance and Microbial Genomics, Bogota, Colombia
- Division of Infectious Diseases, University of Texas McGovern Medical School at Houston, Bogota, Colombia
- Molecular Genetics and Antimicrobial Resistance Unit and International Center for Microbial Genomics, Universidad El Bosque, Bogota, Colombia
| | - Samuel L Aitken
- Division of Pharmacy, University of Texas MD Anderson Cancer Center, Houston
| | - Jessica Galloway Peña
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
| | - Diana Panesso
- Center for Antimicrobial Resistance and Microbial Genomics, Bogota, Colombia
| | - Michael Chang
- Center for Antimicrobial Resistance and Microbial Genomics, Bogota, Colombia
| | - Lorena Diaz
- Molecular Genetics and Antimicrobial Resistance Unit and International Center for Microbial Genomics, Universidad El Bosque, Bogota, Colombia
| | - Rafael Rios
- Molecular Genetics and Antimicrobial Resistance Unit and International Center for Microbial Genomics, Universidad El Bosque, Bogota, Colombia
| | - Yazan Numan
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
| | - Sammi Ghaoui
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
| | - Sruti DebRoy
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
| | - Micah M Bhatti
- Department of Laboratory Medicine, University of Texas MD Anderson Cancer Center, Houston
| | - Dawn E Simmons
- Department of Laboratory Medicine, University of Texas MD Anderson Cancer Center, Houston
| | - Isaam Raad
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
| | - Ray Hachem
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
| | - Stephanie A Folan
- Division of Pharmacy, University of Texas MD Anderson Cancer Center, Houston
| | | | - Awdhesh Kalia
- Graduate Program in Diagnostic Genetics, School of Health Professions, University of Texas MD Anderson Cancer Center, Bogota, Colombia
| | - Samuel A Shelburne
- Center for Antimicrobial Resistance and Microbial Genomics, Bogota, Colombia
- Department of Infectious Diseases, University of Texas MD Anderson Cancer Center, Houston
- Department of Genomic Medicine, University of Texas MD Anderson Cancer Center, Houston
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37
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Nosocomial ventriculitis caused by a meticillin- and linezolid-resistant clone of Staphylococcus epidermidis in neurosurgical patients. J Hosp Infect 2018; 100:406-410. [PMID: 29458065 DOI: 10.1016/j.jhin.2018.02.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 02/12/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND Postneurosurgical ventriculitis is mainly caused by coagulase-negative staphylococci. The rate of linezolid-resistant Staphylococcus epidermidis (LRSE) is increasing worldwide. AIMS To report clinical, epidemiological and microbiological data from a series of ventriculitis cases caused by LRSE in a Spanish hospital between 2013 and 2016. METHODS Cases of LRSE ventriculitis were reviewed retrospectively in a Spanish hospital over a four-year period. Clinical/epidemiological data of the infected patients were reviewed, the isolates involved were typed by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing, and the molecular bases of linezolid resistance were determined. FINDINGS Five cases of LRSE ventriculitis were detected. The patients suffered from cerebral haemorrhage or head trauma that required the placement of an external ventricular drain; spent a relatively long time in the intensive care unit (ICU) (10-26 days); and three out of the five patients had previously been treated with linezolid. All LRSE had the same PFGE pattern, belonged to ST2, and shared an identical mechanism of linezolid resistance. Specifically, all had the G2576T mutation in the V domain of each of the six copies of the 23S rRNA gene, together with the Q136L and M156T mutations and the 71GGR72 insertion in the L3 and L4 ribosomal proteins, respectively. CONCLUSION The high ratio of linezolid consumption in the ICU (7.72-8.10 defined daily dose/100 patient-days) could have selected this resistant clone, which has probably become endemic in the ICU where it could have colonized admitted patients. Infection control and antimicrobial stewardship interventions are essential to prevent the dissemination of this difficult-to-treat pathogen, and to preserve the therapeutic efficacy of linezolid.
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38
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Dissemination ofStaphylococcus epidermidisST22 With Stable, High-Level Resistance to Linezolid and Tedizolid in the Greek-Turkish Region (2008–2016). Infect Control Hosp Epidemiol 2018; 39:492-494. [DOI: 10.1017/ice.2018.5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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39
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Dodou HV, de Morais Batista AH, Sales GWP, de Medeiros SC, Rodrigues ML, Nogueira PCN, Silveira ER, Nogueira NAP. Violacein antimicrobial activity on Staphylococcus epidermidis and synergistic effect on commercially available antibiotics. J Appl Microbiol 2018; 123:853-860. [PMID: 28744944 DOI: 10.1111/jam.13547] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/16/2017] [Accepted: 07/20/2017] [Indexed: 11/30/2022]
Abstract
AIMS The study aimed to assess whether violacein has antimicrobial activity on Staphylococcus epidermidis and synergistically modulates the action of commercially available antimicrobial drugs. METHODS AND RESULTS Violacein showed excellent antimicrobial activity on biofilm-forming and nonbiofilm-forming S. epidermidis strains (ATCC 35984) (ATCC 12228), with bacteriostatic (MIC = 20 μg ml-1 and 10 μg ml-1 respectively) and bactericidal effects (MBC = 20 μg ml-1 for both strains), observed in short periods of exposure. The violacein bactericidal concentration led to S. epidermidis death after 2-3 h of exposure. Additionally, violacein synergistically modulated the activity of different antimicrobial classes on S. epidermidis ATCC 12228 (81·8%; n = 9) and on S. epidermidis ATCC 35984 (54·5%; n = 6), reducing the MIC of these antibiotics by up to 16-fold. CONCLUSION Violacein shows excellent antimicrobial activity on S. epidermidis strains. SIGNIFICANCE AND IMPACT OF THE STUDY Violacein shows the potential for the development of a new drug for the treatment of infections caused by S. epidermidis.
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Affiliation(s)
- H V Dodou
- Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil
| | - A H de Morais Batista
- Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil
| | - G W P Sales
- Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil
| | - S C de Medeiros
- Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil
| | - M L Rodrigues
- Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil
| | - P C N Nogueira
- Department of Organic Chemistry, Federal University of Ceará, Fortaleza, Brazil
| | - E R Silveira
- Department of Organic Chemistry, Federal University of Ceará, Fortaleza, Brazil
| | - N A P Nogueira
- Department of Clinical and Toxicological Analysis, Federal University of Ceará, Fortaleza, Brazil
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40
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The cfr and cfr-like multiple resistance genes. Res Microbiol 2018; 169:61-66. [DOI: 10.1016/j.resmic.2017.12.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 12/07/2017] [Accepted: 12/11/2017] [Indexed: 12/30/2022]
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41
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Combined Effect of the Cfr Methyltransferase and Ribosomal Protein L3 Mutations on Resistance to Ribosome-Targeting Antibiotics. Antimicrob Agents Chemother 2017. [PMID: 28630201 DOI: 10.1128/aac.00862-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Several groups of antibiotics inhibit bacterial growth by binding to bacterial ribosomes. Mutations in ribosomal protein L3 have been associated with resistance to linezolid and tiamulin, which both bind at the peptidyl transferase center in the ribosome. Resistance to these and other antibiotics also occurs through methylation of 23S rRNA at position A2503 by the methyltransferase Cfr. The mutations in L3 and the cfr gene have been found together in clinical isolates, raising the question of whether they have a combined effect on antibiotic resistance or growth. We transformed a plasmid-borne cfr gene into a uL3-depleted Escherichia coli strain containing either wild-type L3 or L3 with one of seven mutations, G147R, Q148F, N149S, N149D, N149R, Q150L, or T151P, expressed from plasmid-carried rplC genes. The L3 mutations are well tolerated, with small to moderate growth rate decreases. The presence of Cfr has a very minor influence on the growth rate. The resistance of the transformants to linezolid, tiamulin, florfenicol, and Synercid (a combination of quinupristin and dalfopristin [Q-D]) was measured by MIC assays. The resistance from Cfr was, in all cases, stronger than the effects of the L3 mutations, but various effects were obtained with the combinations of Cfr and L3 mutations ranging from a synergistic to an antagonistic effect. Linezolid and tiamulin susceptibility varied greatly among the L3 mutations, while no significant effects on florfenicol and Q-D susceptibility were seen. This study underscores the complex interplay between various resistance mechanisms and cross-resistance, even from antibiotics with overlapping binding sites.
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Zahedi Bialvaei A, Rahbar M, Yousefi M, Asgharzadeh M, Samadi Kafil H. Linezolid: a promising option in the treatment of Gram-positives. J Antimicrob Chemother 2016; 72:354-364. [PMID: 27999068 DOI: 10.1093/jac/dkw450] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Linezolid, an oxazolidinone antimicrobial agent that acts by inhibiting protein synthesis in a unique fashion, is used in the treatment of community-acquired pneumonia, skin and soft-tissue infections and other infections caused by Gram-positive bacteria including VRE and methicillin-resistant staphylococci. Currently, linezolid resistance among these pathogens remains low, commonly <1.0%, although the prevalence of antibiotic resistance is increasing in many countries. Therefore, the development of resistance by clinical isolates should prompt increased attention of clinical laboratories to routinely perform linezolid susceptibility testing for this important agent and should be taken into account when considering its therapeutic use. Considering the importance of linezolid in the treatment of infections caused by Gram-positive bacteria, this review was undertaken to optimize the clinical use of this antibiotic.
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Affiliation(s)
| | - Mohammad Rahbar
- Department of Microbiology, Iranian Reference Health Laboratory, Ministry of Health and Medical Education, Tehran, Iran
| | - Mehdi Yousefi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Asgharzadeh
- Biotechnology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Samadi Kafil
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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Detection of a cfr(B) Variant in German Enterococcus faecium Clinical Isolates and the Impact on Linezolid Resistance in Enterococcus spp. PLoS One 2016; 11:e0167042. [PMID: 27893790 PMCID: PMC5125667 DOI: 10.1371/journal.pone.0167042] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 11/08/2016] [Indexed: 11/24/2022] Open
Abstract
The National Reference Centre for Staphylococci and Enterococci in Germany has received an increasing number of clinical linezolid-resistant E. faecium isolates in recent years. Five isolates harbored a cfr(B) variant gene locus the product of which is capable of conferring linezolid resistance. The cfr(B)-like methyltransferase gene was also detected in Clostridium difficile. Antimicrobial susceptibility was determined for cfr(B)-positive and linezolid-resistant E. faecium isolates and two isogenic C. difficile strains. All strains were subjected to whole genome sequencing and analyzed with respect to mutations in the 23S rDNA, rplC, rplD and rplV genes and integration sites of the cfr(B) variant locus. To evaluate methyltransferase function, the cfr(B) variant of Enterococcus and Clostridium was expressed in both E. coli and Enterococcus spp. Ribosomal target site mutations were detected in E. faecium strains but absent in clostridia. Sequencing revealed 99.9% identity between cfr(B) of Enterococcus and cfr of Clostridium. The methyltransferase gene is encoded by transposon Tn6218 which was present in C. difficile Ox3196, truncated in some E. faecium and absent in C. difficile Ox3206. The latter finding explains the lack of linezolid and chloramphenicol resistance in C. difficile Ox3206 and demonstrates for the first time a direct correlation of elevated linezolid MICs in C. difficile upon cfr acquisition. Tn6218 insertion sites revealed novel target loci for integration, both within the bacterial chromosome and as an integral part of plasmids. Importantly, the very first plasmid-association of a cfr(B) variant was observed. Although we failed to measure cfr(B)-mediated resistance in transformed laboratory strains the occurrence of the multidrug resistance gene cfr on putatively highly mobile and/or extrachromosomal DNA in clinical isolates is worrisome with respect to dissemination of antibiotic resistances.
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Schwarz S, Shen J, Kadlec K, Wang Y, Brenner Michael G, Feßler AT, Vester B. Lincosamides, Streptogramins, Phenicols, and Pleuromutilins: Mode of Action and Mechanisms of Resistance. Cold Spring Harb Perspect Med 2016; 6:a027037. [PMID: 27549310 PMCID: PMC5088508 DOI: 10.1101/cshperspect.a027037] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Lincosamides, streptogramins, phenicols, and pleuromutilins (LSPPs) represent four structurally different classes of antimicrobial agents that inhibit bacterial protein synthesis by binding to particular sites on the 50S ribosomal subunit of the ribosomes. Members of all four classes are used for different purposes in human and veterinary medicine in various countries worldwide. Bacteria have developed ways and means to escape the inhibitory effects of LSPP antimicrobial agents by enzymatic inactivation, active export, or modification of the target sites of the agents. This review provides a comprehensive overview of the mode of action of LSPP antimicrobial agents as well as of the mutations and resistance genes known to confer resistance to these agents in various bacteria of human and animal origin.
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Affiliation(s)
- Stefan Schwarz
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut (FLI), 31535 Neustadt-Mariensee, Germany
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, P.R. China
| | - Jianzhong Shen
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, P.R. China
| | - Kristina Kadlec
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut (FLI), 31535 Neustadt-Mariensee, Germany
| | - Yang Wang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, P.R. China
| | - Geovana Brenner Michael
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut (FLI), 31535 Neustadt-Mariensee, Germany
| | - Andrea T Feßler
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut (FLI), 31535 Neustadt-Mariensee, Germany
| | - Birte Vester
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
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Stability of the cargo regions of the cfr-carrying, multiresistance plasmid pSP01 from Staphylococcus epidermidis. Int J Med Microbiol 2016; 306:717-721. [PMID: 27554790 DOI: 10.1016/j.ijmm.2016.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 06/20/2016] [Accepted: 08/14/2016] [Indexed: 11/20/2022] Open
Abstract
This study investigated the stability or instability - i.e. the ability or inability to undergo excision in circular form - of the four cargo regions (cr1 to cr4) of the novel cfr-carrying, multiresistance plasmid pSP01, arboured by a clinical Staphylococcus epidermidis isolate. Only cr4 proved unstable. The stability of cr1 and cr2 was substantially expected. Insertion sequences (ISs) played an important role in the stability of cr3 (the cfr gene context) and in the instability of cr4. Whereas the stability of cfr genetic contexts is associated with the presence of a single IS copy (istAS-istBS in cr3), their instability is associated with two identical, flanking ISs with the same orientation. cr4 is bracketed between two identical IS257 elements, and appears to behave as a composite transposon. Its instability is of interest because of the existence of a closely related cfr plasmid from S. epidermidis (pSP01.1) that differs from pSP01 only by the lack of cr4. An integration/recombination mechanism is suggested to explain how cr4 may have moved to pSP01.1 to form pSP01.
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Ramsay JP, Kwong SM, Murphy RJT, Yui Eto K, Price KJ, Nguyen QT, O'Brien FG, Grubb WB, Coombs GW, Firth N. An updated view of plasmid conjugation and mobilization in Staphylococcus. Mob Genet Elements 2016; 6:e1208317. [PMID: 27583185 PMCID: PMC4993578 DOI: 10.1080/2159256x.2016.1208317] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/15/2016] [Accepted: 06/23/2016] [Indexed: 11/13/2022] Open
Abstract
The horizontal gene transfer facilitated by mobile genetic elements impacts almost all areas of bacterial evolution, including the accretion and dissemination of antimicrobial-resistance genes in the human and animal pathogen Staphylococcus aureus. Genome surveys of staphylococcal plasmids have revealed an unexpected paucity of conjugation and mobilization loci, perhaps suggesting that conjugation plays only a minor role in the evolution of this genus. In this letter we present the DNA sequences of historically documented staphylococcal conjugative plasmids and highlight that at least 3 distinct and widely distributed families of conjugative plasmids currently contribute to the dissemination of antimicrobial resistance in Staphylococcus. We also review the recently documented "relaxase-in trans" mechanism of conjugative mobilization facilitated by conjugative plasmids pWBG749 and pSK41, and discuss how this may facilitate the horizontal transmission of around 90% of plasmids that were previously considered non-mobilizable. Finally, we enumerate unique sequenced S. aureus plasmids with a potential mechanism of mobilization and predict that at least 80% of all non-conjugative S. aureus plasmids are mobilizable by at least one mechanism. We suggest that a greater research focus on the molecular biology of conjugation is essential if we are to recognize gene-transfer mechanisms from our increasingly in silico analyses.
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Affiliation(s)
- Joshua P. Ramsay
- School of Biomedical Sciences and Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- ACCESS Typing and Research, School of Veterinary Sciences and Life Sciences, Murdoch University and School of Biomedical Sciences, Curtin University, Perth, WA, Australia
| | - Stephen M. Kwong
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
| | - Riley J. T. Murphy
- School of Biomedical Sciences and Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- ACCESS Typing and Research, School of Veterinary Sciences and Life Sciences, Murdoch University and School of Biomedical Sciences, Curtin University, Perth, WA, Australia
| | - Karina Yui Eto
- School of Biomedical Sciences and Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
- ACCESS Typing and Research, School of Veterinary Sciences and Life Sciences, Murdoch University and School of Biomedical Sciences, Curtin University, Perth, WA, Australia
- School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA, Australia
| | - Karina J. Price
- School of Biomedical Sciences and Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Quang T. Nguyen
- School of Biomedical Sciences and Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Frances G. O'Brien
- ACCESS Typing and Research, School of Veterinary Sciences and Life Sciences, Murdoch University and School of Biomedical Sciences, Curtin University, Perth, WA, Australia
| | - Warren B. Grubb
- ACCESS Typing and Research, School of Veterinary Sciences and Life Sciences, Murdoch University and School of Biomedical Sciences, Curtin University, Perth, WA, Australia
| | - Geoffrey W. Coombs
- ACCESS Typing and Research, School of Veterinary Sciences and Life Sciences, Murdoch University and School of Biomedical Sciences, Curtin University, Perth, WA, Australia
- PathWest Laboratory Medicine–WA, Fiona Stanley Hospital, Perth, WA, Australia
| | - Neville Firth
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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First Report of cfr-Carrying Plasmids in the Pandemic Sequence Type 22 Methicillin-Resistant Staphylococcus aureus Staphylococcal Cassette Chromosome mec Type IV Clone. Antimicrob Agents Chemother 2016; 60:3007-15. [PMID: 26953212 PMCID: PMC4862533 DOI: 10.1128/aac.02949-15] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/29/2016] [Indexed: 12/14/2022] Open
Abstract
Linezolid is often the drug of last resort for serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Linezolid resistance is mediated by mutations in 23S rRNA and genes for ribosomal proteins; cfr, encoding phenicol, lincosamide, oxazolidinone, pleuromutilin, and streptogramin A (PhLOPSA) resistance; its homologue cfr(B); or optrA, conferring oxazolidinone and phenicol resistance. Linezolid resistance is rare in S. aureus, and cfr is even rarer. This study investigated the clonality and linezolid resistance mechanisms of two MRSA isolates from patients in separate Irish hospitals. Isolates were subjected to cfr PCR, PhLOPSA susceptibility testing, 23S rRNA PCR and sequencing, DNA microarray profiling, spa typing, pulsed-field gel electrophoresis (PFGE), plasmid curing, and conjugative transfer. Whole-genome sequencing was used for single-nucleotide variant (SNV) analysis, multilocus sequence typing, L protein mutation identification, cfr plasmid sequence analysis, and optrA and cfr(B) detection. Isolates M12/0145 and M13/0401 exhibited linezolid MICs of 64 and 16 mg/liter, respectively, and harbored identical 23S rRNA and L22 mutations, but M12/0145 exhibited the mutation in 2/6 23S rRNA alleles, compared to 1/5 in M13/0401. Both isolates were sequence type 22 MRSA staphylococcal cassette chromosome mec type IV (ST22-MRSA-IV)/spa type t032 isolates, harbored cfr, exhibited the PhLOPSA phenotype, and lacked optrA and cfr(B). They differed by five PFGE bands and 603 SNVs. Isolate M12/0145 harbored cfr and fexA on a 41-kb conjugative pSCFS3-type plasmid, whereas M13/0401 harbored cfr and lsa(B) on a novel 27-kb plasmid. This is the first report of cfr in the pandemic ST22-MRSA-IV clone. Different cfr plasmids and mutations associated with linezolid resistance in genotypically distinct ST22-MRSA-IV isolates highlight that prudent management of linezolid use is essential.
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Cuny C, Arnold P, Hermes J, Eckmanns T, Mehraj J, Schoenfelder S, Ziebuhr W, Zhao Q, Wang Y, Feßler AT, Krause G, Schwarz S, Witte W. Occurrence of cfr-mediated multiresistance in staphylococci from veal calves and pigs, from humans at the corresponding farms, and from veterinarians and their family members. Vet Microbiol 2016; 200:88-94. [PMID: 27102205 DOI: 10.1016/j.vetmic.2016.04.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 03/26/2016] [Accepted: 04/03/2016] [Indexed: 11/27/2022]
Abstract
This study reports on the emergence of linezolid-resistant coagulase-negative staphylococci (CoNS) containing the multiresistance gene cfr in veal calves and pigs, as well as in humans exposed to these animals. CoNS (Staphylococcus auricularis, Staphylococcus cohnii, Staphylococcus lentus, Staphylococcus kloosii, Staphylococcus sciuri, Staphylococcus simulans), but not Staphylococcus aureus, carrying the gene cfr were detected in samples of 12 out of 52 calves at three farms which had a history of florfenicol use. Nasal swabs from 10 humans living on these farms were negative for cfr-carrying staphylococci. Nasal swabs taken from 142 calves at 16 farms in the same area that did not use florfenicol were also negative for cfr-carrying staphylococci. 14 cfr-carrying CoNS (S. kloosii, S. saprophyticus, S. simulans) were detected in three of eight conventional pig farms investigated. One of 12 humans living on these farms harboured a cfr-carrying S. cohnii. Among the nasal swabs taken from 169 veterinarians from all over Germany, four (2.3%) were positive for cfr-carrying CoNS (three S. epidermidis, one S. saprophyticus), and three (1.1%) of 263 contact persons of this group also harboured cfr-carrying CoNS (one S. epidermidis, two S. saprophyticus). In vitro conjugation of cfr by filter mating to S. aureus 8325-4 was possible for 10 of 34CoNS and the cfr gene was associated with plasmids of 38-40kb. Moreover, a total of 363 humans of a German municipal community were investigated for nasal carriage of cfr-carrying staphylococci to get an idea whether such isolates are disseminated as nasal colonizers in non-hospitalized humans in the community, were all negative.
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Affiliation(s)
| | | | - Julia Hermes
- Robert Koch Institute, Department of Infectious Disease Epidemiology, Germany
| | - Tim Eckmanns
- Robert Koch Institute, Department of Infectious Disease Epidemiology, Germany
| | - Jaishri Mehraj
- Helmholtz Centre for Infection Research, Epidemiology Department, Germany; PhD Program Epidemiology, Hannover Biomedical Research School and Helmholtz Center for Infection Research, Germany
| | - Sonja Schoenfelder
- Institute for Molecular Infection Biology, University of Wuerzburg, Germany
| | - Wilma Ziebuhr
- Institute for Molecular Infection Biology, University of Wuerzburg, Germany
| | - Qin Zhao
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, PR China
| | - Yang Wang
- Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing, PR China
| | - Andrea T Feßler
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Neustadt-Mariensee, Germany
| | - Gérard Krause
- Helmholtz Centre for Infection Research, Epidemiology Department, Germany; Hannover Medical School, Germany
| | - Stefan Schwarz
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Neustadt-Mariensee, Germany
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Mendes RE, Hogan PA, Jones RN, Sader HS, Flamm RK. Surveillance for linezolid resistance via the Zyvox®Annual Appraisal of Potency and Spectrum (ZAAPS) programme (2014): evolving resistance mechanisms with stable susceptibility rates. J Antimicrob Chemother 2016; 71:1860-5. [DOI: 10.1093/jac/dkw052] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/08/2016] [Indexed: 11/13/2022] Open
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Ntokou E, Hansen LH, Kongsted J, Vester B. Biochemical and Computational Analysis of the Substrate Specificities of Cfr and RlmN Methyltransferases. PLoS One 2015; 10:e0145655. [PMID: 26700482 PMCID: PMC4689488 DOI: 10.1371/journal.pone.0145655] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 12/07/2015] [Indexed: 12/15/2022] Open
Abstract
Cfr and RlmN methyltransferases both modify adenine 2503 in 23S rRNA (Escherichia coli numbering). RlmN methylates position C2 of adenine while Cfr methylates position C8, and to a lesser extent C2, conferring antibiotic resistance to peptidyl transferase inhibitors. Cfr and RlmN show high sequence homology and may be evolutionarily linked to a common ancestor. To explore their individual specificity and similarity we performed two sets of experiments. We created a homology model of Cfr and explored the C2/C8 specificity using docking and binding energy calculations on the Cfr homology model and an X-ray structure of RlmN. We used a trinucleotide as target sequence and assessed its positioning at the active site for methylation. The calculations are in accordance with different poses of the trinucleotide in the two enzymes indicating major evolutionary changes to shift the C2/C8 specificities. To explore interchangeability between Cfr and RlmN we constructed various combinations of their genes. The function of the mixed genes was investigated by RNA primer extension analysis to reveal methylation at 23S rRNA position A2503 and by MIC analysis to reveal antibiotic resistance. The catalytic site is expected to be responsible for the C2/C8 specificity and most of the combinations involve interchanging segments at this site. Almost all replacements showed no function in the primer extension assay, apart from a few that had a weak effect. Thus Cfr and RlmN appear to be much less similar than expected from their sequence similarity and common target.
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Affiliation(s)
- Eleni Ntokou
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
- * E-mail:
| | - Lykke Haastrup Hansen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Jacob Kongsted
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - Birte Vester
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
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