{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,11]],"date-time":"2025-09-11T17:02:35Z","timestamp":1757610155678,"version":"3.44.0"},"reference-count":29,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,9,3]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n<jats:p><jats:italic>Acinetobacter baumannii<\/jats:italic> (<jats:italic>A. baumannii<\/jats:italic>) is a Gram-negative, nonfermenting bacterium implicated as a major cause of opportunistic infections in healthcare settings because it is a multidrug-resistant organism. Tigecycline was developed to circumvent the prevalent mechanism of <jats:italic>A. baumannii<\/jats:italic> resistance against tetracycline. This study aims to determine the frequency of tigecycline resistance and to characterize the tigecycline-resistant <jats:italic>tet(Y)<\/jats:italic>, <jats:italic>tet(X),<\/jats:italic> and <jats:italic>tet(A)<\/jats:italic> genes in <jats:italic>A. baumannii<\/jats:italic> clinical isolates. A descriptive cross-sectional study was conducted at Lahore General Hospital (LGH), Lahore, Pakistan, from February 2023 to February 2024. A total of 195 <jats:italic>A. baumannii<\/jats:italic> samples were isolated from various samples collected from patients admitted to the intensive care unit of LGH over a period of 1 year. The antimicrobial susceptibility of <jats:italic>A. baumannii<\/jats:italic> was assessed using the Kirby\u2013Bauer disc diffusion assay, and the results were reported according to the Clinical and Laboratory Standards Institute 2022 guidelines. The activity of tigecycline was reported according to the British Society for Antimicrobial Chemotherapy 2021 guidelines. The detection of tigecycline resistance genes <jats:italic>tet(Y), tet(X),<\/jats:italic> and <jats:italic>tet(A)<\/jats:italic> was performed using polymerase chain reaction, and the amplified products were confirmed using Sanger sequencing. <jats:italic>Acinetobacter baumannii<\/jats:italic> were resistant to multiple antibiotics. Minocycline was the most effective antibiotic, with 10.8% resistance, whereas cefotaxime was the least effective, with 74.4% resistance in 195 isolates of <jats:italic>A. baumannii<\/jats:italic>. Resistance to tigecycline was detected in 9% of isolates of <jats:italic>A. baumannii<\/jats:italic>. The <jats:italic>tet(A)<\/jats:italic> gene was the most frequently found gene, present in 20% of the tigecycline-resistant isolates, followed by <jats:italic>tet(X)<\/jats:italic> and <jats:italic>tet(Y)<\/jats:italic> genes in 18% and 9% of isolates, respectively. A high frequency of plasmid-mediated tigecycline resistance was detected in <jats:italic>A. baumannii<\/jats:italic> samples, with a high prevalence of <jats:italic>tet(Y), tet(X),<\/jats:italic> and <jats:italic>tet(A)<\/jats:italic> genes. This emphasizes the need for antibiotic stewardship, the detection of resistance profiles, and understanding underlying molecular mechanisms to plan clinical management effectively.<\/jats:p>","DOI":"10.4269\/ajtmh.24-0295","type":"journal-article","created":{"date-parts":[[2025,6,24]],"date-time":"2025-06-24T11:34:48Z","timestamp":1750764888000},"page":"683-688","source":"Crossref","is-referenced-by-count":0,"title":["Detection of the Tigecycline Resistance-Mediating tet(Y) Gene in Acinetobacter baumannii Isolates from Intensive Care Unit Patients in Pakistan"],"prefix":"10.4269","volume":"113","author":[{"given":"Zainab","family":"Tufail","sequence":"first","affiliation":[{"name":"Lahore\/Postgraduate Medical Institute, Lahore General Hospital, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kokab","family":"Jabeen","sequence":"additional","affiliation":[{"name":"Lahore\/Postgraduate Medical Institute, Lahore General Hospital, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mahnoor","family":"Chaudhry","sequence":"additional","affiliation":[{"name":"Lahore\/Postgraduate Medical Institute, Lahore General Hospital, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sana","family":"Mustafa","sequence":"additional","affiliation":[{"name":"Lahore\/Postgraduate Medical Institute, Lahore General Hospital, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sidrah","family":"Saleem","sequence":"additional","affiliation":[{"name":"University of Health Sciences, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Afshan","family":"Zia","sequence":"additional","affiliation":[{"name":"University of Health Sciences, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fareeha","family":"Imran","sequence":"additional","affiliation":[{"name":"Lahore\/Postgraduate Medical Institute, Lahore General Hospital, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Waleed","family":"Tariq","sequence":"additional","affiliation":[{"name":"Mayo Hospital, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhammad Junaid","family":"Tahir","sequence":"additional","affiliation":[{"name":"Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhammad Sohaib","family":"Asghar","sequence":"additional","affiliation":[{"name":"AdventHealth Sebring, Sebring, Florida"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"2795","reference":[{"key":"b1","series-title":"Emerg Microbes Infect","first-page":"1404","article-title":"Novel tigecycline resistance mechanisms in Acinetobacter baumannii are mediated by mutations in adeS, rpoB, and 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