{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T18:08:09Z","timestamp":1792001289278,"version":"4.4.0"},"reference-count":31,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T00:00:00Z","timestamp":1716422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objective: Enterococci are typically found in a healthy human gastrointestinal tract but can cause severe infections in immunocompromised patients. Such infections are treated with antibiotics. This study addresses the rising concern of antimicrobial resistance (AMR) in Enterococci, focusing on the prevalence of vancomycin-resistant enterococcus (VRE) strains. Materials and Methods: The pilot study involved 140 Enterococci isolates collected between 2021 and 2022 from two multidisciplinary hospitals (with and without local therapeutic drug monitoring protocol of vancomycin) in Latvia. Microbiological assays and whole genome sequencing were used. AMR gene prevalence with resistance profiles were determined and the genetic relationship and outbreak evaluation were made by applying core genome multi-locus sequence typing (cgMLST). Results: The acquired genes and mutations were responsible for resistance against 10 antimicrobial classes, including 25.0% of isolates expressing resistance to vancomycin, predominantly of the vanB type. Genetic diversity among E. faecalis and E. faecium isolates was observed and seven potential outbreak clusters were identified, three of them containing sequence types ST6, ST78 and ST80. The prevalence of vancomycin resistance was highest in the hospital without a therapeutic drug-monitoring protocol and in E. faecium. Notably, a case of linezolid resistance due to a mutation was documented. Conclusions: The study illustrates the concerning prevalence of multidrug-resistant Enterococci in Latvian hospitals, showcasing the rather widespread occurrence of vancomycin-resistant strains. This highlights the urgency of implementing efficient infection control mechanisms and the need for continuous VRE surveillance in Latvia to define the scope and pattern of the problem, influencing clinical decision making and planning further preventative measures.<\/jats:p>","DOI":"10.3390\/medicina60060850","type":"journal-article","created":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T09:58:47Z","timestamp":1716458327000},"page":"850","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Evaluation of Antimicrobial Resistance in Clinical Isolates of Enterococcus spp. Obtained from Hospital Patients in Latvia"],"prefix":"10.3390","volume":"60","author":[{"given":"Linda","family":"Labecka","sequence":"first","affiliation":[{"name":"Institute of Food Safety, Animal Health and Environment \u201cBIOR\u201d, Lejupes Street 3, LV-1076 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3236-2001","authenticated-orcid":false,"given":"Juris","family":"\u0136ibilds","sequence":"additional","affiliation":[{"name":"Institute of Food Safety, Animal Health and Environment \u201cBIOR\u201d, Lejupes Street 3, LV-1076 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3472-865X","authenticated-orcid":false,"given":"Aivars","family":"C\u012brulis","sequence":"additional","affiliation":[{"name":"Institute of Food Safety, Animal Health and Environment \u201cBIOR\u201d, Lejupes Street 3, LV-1076 Riga, Latvia"},{"name":"Faculty of Biology, University of Latvia, Jelgavas Street 1, LV-1004 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Evel\u012bna","family":"\u010ceir\u0101ne","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, Riga Stradins University, Dzirciema Street 16, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Indra","family":"Zelti\u0146a","sequence":"additional","affiliation":[{"name":"Department of Infectology, Riga Stradi\u0146\u0161 University, Dzirciema Street 16, LV-1007 Riga, Latvia"},{"name":"Riga East Clinical University Hospital, Hipokrata Street 2, LV-1038 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3671-1213","authenticated-orcid":false,"given":"Aigars","family":"Reinis","sequence":"additional","affiliation":[{"name":"Department of Biology and Microbiology, Riga Stradi\u0146\u0161 University, Dzirciema Street 16, LV-1007 Riga, Latvia"},{"name":"Pauls Stradi\u0146\u0161 Clinical University Hospital, Pilso\u0146u Street 13, LV-1002 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barba","family":"Vilima","sequence":"additional","affiliation":[{"name":"Vidzeme Hospital, Jumaras Street 195, LV-4201 Valmiera, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dace","family":"Rudz\u012bte","sequence":"additional","affiliation":[{"name":"Riga East Clinical University Hospital, Hipokrata Street 2, LV-1038 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3674-8822","authenticated-orcid":false,"given":"Ren\u0101rs","family":"Erts","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Latvia, Rai\u0146a bulv\u0101ris 19, LV-1586 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3691-5520","authenticated-orcid":false,"given":"Inga","family":"Mauli\u0146a","sequence":"additional","affiliation":[{"name":"Riga East Clinical University Hospital, Hipokrata Street 2, LV-1038 Riga, Latvia"},{"name":"Vidzeme Hospital, Jumaras Street 195, LV-4201 Valmiera, Latvia"},{"name":"Department of Pharmaceutical Chemistry, Riga Stradi\u0146\u0161 University, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9144-8799","authenticated-orcid":false,"given":"Dace","family":"Bandere","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Riga Stradi\u0146\u0161 University, LV-1007 Riga, Latvia"},{"name":"Baltic Biomaterials Centre of Excellence, Headquarters at Riga Technical University, LV-1658 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0726-3375","authenticated-orcid":false,"given":"Angelika","family":"Kr\u016bmi\u0146a","sequence":"additional","affiliation":[{"name":"Institute of Food Safety, Animal Health and Environment \u201cBIOR\u201d, Lejupes Street 3, LV-1076 Riga, Latvia"},{"name":"Department of Infectology, Riga Stradi\u0146\u0161 University, Dzirciema Street 16, LV-1007 Riga, 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Dis. Clin. N. Am."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Fiore, E., Van Tyne, D., and Gilmore, M.S. (2019). Pathogenicity of Enterococci. Microbiol Spectr., 7.","DOI":"10.1128\/microbiolspec.GPP3-0053-2018"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2001628","DOI":"10.2807\/1560-7917.ES.2021.26.45.2001628","article-title":"Hospital-acquired infections caused by enterococci: A systematic review and meta-analysis, WHO European Region, 1 January 2010 to 4 February 2020","volume":"26","author":"Brinkwirth","year":"2021","journal-title":"Euro Surveill."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e00058-18","DOI":"10.1128\/CMR.00058-18","article-title":"The Enterococcus: A Model of Adaptability to Its Environment","volume":"32","author":"Rice","year":"2019","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_7","unstructured":"The European Committee on Antimicrobial Susceptibility Testing\u2014EUCAST (2024, January 16). Expected Phenotypes Version 1.0. Available online: https:\/\/www.eucast.org\/fileadmin\/src\/media\/PDFs\/EUCAST_files\/Expert_Rules\/2022\/Expected_Phenotypes_Tables_v4.0_20220211.pdf."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1139\/cjm-2019-0309","article-title":"Renaissance of vancomycin: Approaches for breaking antibiotic resistance in multidrug-resistant bacteria","volume":"66","author":"Kleist","year":"2020","journal-title":"Can. J. Microbiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"953","DOI":"10.1016\/j.idc.2021.07.002","article-title":"Vancomycin-Resistant Enterococci: Epidemiology, Infection Prevention, and Control","volume":"35","author":"Joshi","year":"2021","journal-title":"Infect. Dis. Clin. N. Am."},{"key":"ref_10","unstructured":"(2023, June 16). EUCAST: AST of Bacteria. Available online: https:\/\/www.eucast.org\/ast_of_bacteria."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"The Galaxy Community (2022). The Galaxy platform for accessible, reproducible and collaborative biomedical analyses: 2022 update. Nucleic Acids Res., 50, W345\u2013W351.","DOI":"10.1093\/nar\/gkac610"},{"key":"ref_12","unstructured":"(2023, June 16). Center for Genomic Epidemiology. Available online: https:\/\/www.genomicepidemiology.org\/contact\/."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e00311-22","DOI":"10.1128\/jcm.00311-22","article-title":"Core Genome Multilocus Sequence Typing Scheme for Improved Characterization and Epidemiological Surveillance of Pathogenic Brucella","volume":"60","author":"Thomas","year":"2022","journal-title":"J. Clin. Microbiol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1395","DOI":"10.1101\/gr.232397.117","article-title":"GrapeTree: Visualization of core genomic relationships among 100,000 bacterial pathogens","volume":"28","author":"Zhou","year":"2018","journal-title":"Genome Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1016\/j.mimet.2005.03.018","article-title":"Identification of plasmids by PCR-based replicon typing","volume":"63","author":"Carattoli","year":"2005","journal-title":"J. Microbiol. Methods"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Neumann, B., Prior, K., Bender, J.K., Harmsen, D., Klare, I., Fuchs, S., Bethe, A., Z\u00fchlke, D., G\u00f6hler, A., and Schwarz, S. (2019). A Core Genome Multilocus Sequence Typing Scheme for Enterococcus faecalis. J. Clin. Microbiol., 57.","DOI":"10.1128\/JCM.01686-18"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"3788","DOI":"10.1128\/JCM.01946-15","article-title":"Core Genome Multilocus Sequence Typing Scheme for High- Resolution Typing of Enterococcus faecium","volume":"53","author":"Pinholt","year":"2015","journal-title":"J. Clin. Microbiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.idc.2016.02.004","article-title":"Multidrug-Resistant Bacteria in the Community: Trends and Lessons Learned","volume":"30","author":"Paterson","year":"2016","journal-title":"Infect. Dis. Clin. N. Am."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"426","DOI":"10.30699\/ijp.2021.520570.2542","article-title":"The role of Gene Mutations (gyrA, parC) in Resistance to Ciprofloxacin in Clinical Isolates of Pseudomonas Aeruginosa","volume":"16","author":"Arabameri","year":"2021","journal-title":"Iran. J. Pathol."},{"key":"ref_20","first-page":"179","article-title":"Resistance to \u03b2-lactams in enterococci","volume":"51","author":"Gagetti","year":"2019","journal-title":"Rev. Argent. Microbiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1759","DOI":"10.2147\/DDDT.S164515","article-title":"Linezolid: A review of its properties, function, and use in critical care","volume":"12","author":"Hashemian","year":"2018","journal-title":"Drug Des. Dev. Ther."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1445","DOI":"10.1111\/j.1365-2958.2004.04368.x","article-title":"Clp ATPases are required for stress tolerance, intracellular replication and biofilm formation in Staphylococcus aureus","volume":"54","author":"Frees","year":"2004","journal-title":"Mol. Microbiol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1002\/pmic.200700925","article-title":"ClpL is essential for induction of thermotolerance and is potentially part of the HrcA regulon in Lactobacillus gasseri","volume":"8","author":"Suokko","year":"2008","journal-title":"Proteomics"},{"key":"ref_24","unstructured":"European Centre for Disease Prevention and Control (2023). Antimicrobial Resistance in the EU\/EEA (EARS-Net)\u2014Annual Epidemiological Report 2022."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1186\/s13073-020-00825-3","article-title":"Mode and dynamics of vanA-type vancomycin resistance dissemination in Dutch hospitals","volume":"13","author":"Top","year":"2021","journal-title":"Genome Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1900503","DOI":"10.2807\/1560-7917.ES.2019.24.34.1900503","article-title":"Surveillance of vancomycin-resistant enterococci reveals shift in dominating clones and national spread of a vancomycin-variable vanA Enterococcus faecium ST1421-CT1134 clone, Denmark, 2015 to March 2019","volume":"24","author":"Hammerum","year":"2019","journal-title":"Euro Surveill."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"100732","DOI":"10.1016\/j.drup.2020.100732","article-title":"Thirty years of VRE in Germany\u2014\u201cexpect the unexpected\u201d: The view from the National Reference Centre for Staphylococci and Enterococci","volume":"53","author":"Werner","year":"2020","journal-title":"Drug Resist. Updates"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Guffey, A.A., and Loll, P.J. (2021). Regulation of Resistance in Vancomycin-Resistant Enterococci: The VanRS Two-Component System. Microorganisms, 9.","DOI":"10.3390\/microorganisms9102026"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/S0163-4453(96)80003-X","article-title":"Mechanisms of glycopeptide resistance in enterococci","volume":"32","author":"Arthur","year":"1996","journal-title":"J. Infect."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1046\/j.1365-2125.1998.00770.x","article-title":"Best practice in therapeutic drug monitoring","volume":"46","author":"Gross","year":"1998","journal-title":"Br. J. Clin. Pharmacol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"271","DOI":"10.2165\/00003088-199528040-00001","article-title":"Community-Based Therapeutic Drug Monitoring","volume":"28","author":"Campbell","year":"1995","journal-title":"Clin. Pharmacokinet."}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/60\/6\/850\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:47:09Z","timestamp":1760107629000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/60\/6\/850"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,5,23]]},"references-count":31,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2024,6]]}},"alternative-id":["medicina60060850"],"URL":"https:\/\/doi.org\/10.3390\/medicina60060850","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,5,23]]}}}