{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T06:01:27Z","timestamp":1792648887355,"version":"4.5.0"},"reference-count":46,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,5,29]],"date-time":"2023-05-29T00:00:00Z","timestamp":1685318400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>This study explored the prevalence of multi-drug resistance and virulence factors of enterococcal isolates obtained from various clinical specimens (n = 1575) including urine, blood, pus, tissue, catheter, vaginal wash, semen, and endotracheal secretions. Out of 862 enterococcal isolates, 388 (45%), 246 (29%), 120 (14%), and 108 (13%) were identified as Enterococcus\u00a0faecalis, Enterococcus\u00a0faecium, Enterococcus\u00a0durans, and Enterococcus\u00a0hirae, respectively, using standard morphological and biochemical methods. The antibiotic resistance profile of all these enterococcal isolates was checked using the disc diffusion technique. High-level resistance was observed for benzylpenicillin (70%) and vancomycin (43%) among E. faecalis and E. faecium isolates, respectively. This study also revealed the prevalence of \u2018multi-drug resistance (resistant to 3 antibiotic groups)\u2019 among the vancomycin-resistant enterococcal strains, and this was about 11% (n = 91). The virulence determinants associated with vancomycin resistance (VR) were determined phenotypically and genotypically. About 70 and 39% of E. faecalis and E. faecium isolates showed to be positive for all four virulence factors (gelatinase, protease, hemolysin, and biofilm). Among the several virulence genes, gelE was the most common virulence gene with a prevalence rate of 76 and 69% among E. faecalis and E. faecium isolates, respectively. More than 50% of VRE isolates harbored other virulence genes, such esp, asa, ace, and cylA. Similarly, the majority of the VR enterococcal isolates (n = 88\/91) harbored vanA gene and none of them harbored vanB gene. These results disclose the importance of VR E. faecalis and E. faecium and the associated virulence factors involved in the persistence of infections in clinical settings.<\/jats:p>","DOI":"10.3390\/antibiotics12060981","type":"journal-article","created":{"date-parts":[[2023,5,30]],"date-time":"2023-05-30T02:33:27Z","timestamp":1685414007000},"page":"981","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Antibiotic Susceptibility Patterns and Virulence-Associated Factors of Vancomycin-Resistant Enterococcal Isolates from Tertiary Care Hospitals"],"prefix":"10.3390","volume":"12","author":[{"given":"Arockia","family":"Doss Susai backiam","sequence":"first","affiliation":[{"name":"Department of Microbiology, Vivekanandha College of Arts and Science for Women (Autonomous), Tiruchengode 637303, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6051-7229","authenticated-orcid":false,"given":"Senbagam","family":"Duraisamy","sequence":"additional","affiliation":[{"name":"Department of Marine Biotechnology, Bharathidasan University, Tiruchirappalli 620024, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5178-8040","authenticated-orcid":false,"given":"Palaniyandi","family":"Karuppaiya","sequence":"additional","affiliation":[{"name":"Department of Marine Biotechnology, Bharathidasan University, Tiruchirappalli 620024, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4117-9695","authenticated-orcid":false,"given":"Senthilkumar","family":"Balakrishnan","sequence":"additional","affiliation":[{"name":"Division of Biological Sciences, Tamil Nadu State Council for Science and Technology, Chennai 600025, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Balaji","family":"Chandrasekaran","sequence":"additional","affiliation":[{"name":"Irma Lerma Rangel School of Pharmacy, Texas A & M University, Kingsville, TX 77843, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anbarasu","family":"Kumarasamy","sequence":"additional","affiliation":[{"name":"Department of Marine Biotechnology, Bharathidasan University, Tiruchirappalli 620024, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amutha","family":"Raju","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Periyar University Centre for Post Graduate and Research Studies, Dharmapuri 635205, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7936156","DOI":"10.1155\/2019\/7936156","article-title":"Characterization of clinical isolates of enterococci with special reference to glycopeptide susceptibility at a tertiary care center of Eastern Nepal","volume":"2019","author":"Karna","year":"2019","journal-title":"Int. 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