{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T04:16:12Z","timestamp":1788322572791,"version":"build-2803163510"},"reference-count":38,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"1","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"abstract":"\n Background:<\/jats:title>\n \n Enterococci<\/jats:italic>\n may develop resistance to linezolid through chromosomal mutations that involve specific linezolid resistance genes, such as\n cfr<\/jats:italic>\n ,\n optrA<\/jats:italic>\n , and\n poxtA<\/jats:italic>\n . The objective of this study was to evaluate the antibiotic susceptibility of enterococcal isolates and identify\n cfr<\/jats:italic>\n ,\n optrA<\/jats:italic>\n , and\n poxtA<\/jats:italic>\n genes in MDR isolates.\n <\/jats:p>\n <\/jats:sec>\n \n Materials and Methods:<\/jats:title>\n \n Enterococcal isolates were collected from various clinical specimens at Al-Zahra, Amin, and Khorshid Hospitals in Isfahan. The\n Enterococcus<\/jats:italic>\n isolates were identified as belonging to the\n E. faecalis<\/jats:italic>\n and\n E. faecium<\/jats:italic>\n species by using specific gene (D alanine D alanine ligase\n ddl)<\/jats:italic>\n sets in PCR. To detect\n cfr, optrA<\/jats:italic>\n , and\n poxtA<\/jats:italic>\n genes among the species, a multiplex-PCR assay was performed.\n <\/jats:p>\n <\/jats:sec>\n \n Results:<\/jats:title>\n \n Out of 175 isolates\n , E. faecalis<\/jats:italic>\n predominated 129\/175 (73.7%). Furthermore, the prevalence of vancomycin-resistant\n Enterococci<\/jats:italic>\n (VRE) and linezolid-resistant\n Enterococci<\/jats:italic>\n (LRE) was 29.7% and 4%, respectively. The overall prevalence of MDR was 91.1%, 68.9%, and 66.6% of\n E. faecium<\/jats:italic>\n ,\n E. faecalis<\/jats:italic>\n , and other\n Enterococcus spp<\/jats:italic>\n ., respectively. Interestingly, the frequency of\n optrA<\/jats:italic>\n (71.4%) in\n E. faecium<\/jats:italic>\n and\n poxtA<\/jats:italic>\n and\n crf<\/jats:italic>\n (42.8%) in\n E. faecalis<\/jats:italic>\n were detected among LRE species. A statistically significant relationship (\n P<\/jats:italic>\n < 0.05) was found between the presence of the three genes and the occurrence of LRE.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion:<\/jats:title>\n \n This is the first study to report the detection of linezolid resistance genes (\n cfr<\/jats:italic>\n ,\n optrA<\/jats:italic>\n , and\n poxtA<\/jats:italic>\n ) in clinical\n Enterococcus spp.<\/jats:italic>\n isolates from Iran, conducted at Isfahan University of Medical Sciences hospitals. The emergence of enterococcal strains that resist linezolid is concerning as it can lead to the spread of resistant strains among patients, resulting in treatment failure.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.4103\/abr.abr_74_23","type":"journal-article","created":{"date-parts":[[2023,7,31]],"date-time":"2023-07-31T00:47:21Z","timestamp":1690764441000},"update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":7,"title":["Detection of Genes Related to Linezolid Resistance (poxtA, cfr, and optrA) in Clinical Isolates of Enterococcus spp. from Humans: A First Report from Iran"],"prefix":"10.4103","volume":"12","author":[{"given":"Majid","family":"Torabi","sequence":"first","affiliation":[{"name":"Department of Bacteriology and Virology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, 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