{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T13:34:59Z","timestamp":1787578499659,"version":"build-2736575974"},"reference-count":0,"publisher":"Knowledge E DMCC","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJM"],"abstract":"<jats:p>Background and Objectives: Ventilator-associated pneumonia (VAP) caused by carbapenem-resistant Gram-negative bac- teria is a serious ICU challenge. This study determined the prevalence, antimicrobial susceptibility profiles, and phenotypic carbapenemase resistance mechanisms of Gram-negative isolates from VAP patients in two tertiary hospitals in Karachi, Pakistan.\r\nMaterials and Methods: We included 104 consecutive cases of VAP (July 2021\u2013January 2023). A total of 67 carbapen- em-resistant Gram-negative isolates were identified and tested. Antibiotic susceptibility was assessed by disk diffusion and broth micro dilution, according to CLSI and EUCAST guidelines. Modified and enhanced carbapenem inactivation methods (mCIM\/eCIM) were used to distinguish metallo-\u03b2-lactamase (MBL) and serine carbapenemase production.\r\nResults:The mean age was 44.6 \u00b1 18.3 years; 52.2% were male. Early-onset VAP accounted for 37.3% and late-onset for62.7%. The most frequent pathogens were Acinetobacter baumannii (49.3%, 33\/67) and Klebsiella pneumoniae (20.9%,14\/67). Notably, 67% of isolates produced MBLs, and 33% produced serine carbapenemases (phenotypically). The preva-lence of multidrug-resistant (MDR), extensively drug-resistant (XDR), and pan drug-resistant (PDR) phenotypes was 42.6%,31.3%, and 19.4%, respectively.\r\nConclusion: VAP in our ICUs was dominated by A. baumannii and K. pneumoniae with high levels of MBL-mediated resis- tance. These findings highlight the urgent need for surveillance, stewardship, and new therapeutic options.\r\n\u00a0<\/jats:p>","DOI":"10.18502\/ijm.v17i5.19885","type":"journal-article","created":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T07:59:12Z","timestamp":1760428752000},"source":"Crossref","is-referenced-by-count":1,"title":["Distribution of MBL and serine-\u03b2-lactamase-producing pathogens in ventilator-associated pneumonia: insights into MDR and XDR strains"],"prefix":"10.18502","author":[{"given":"Zeb","family":"Hussain","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asma","family":"Naim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ambreen","family":"Fatima","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asad","family":"Karim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fakhur","family":"Uddin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Surraya","family":"Shams","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"7770","published-online":{"date-parts":[[2025,10,13]]},"container-title":["Iranian Journal of Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/publish.kne-publishing.com\/index.php\/IJM\/article\/download\/19885\/18577","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/publish.kne-publishing.com\/index.php\/IJM\/article\/download\/19885\/18577","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T11:19:07Z","timestamp":1772104747000},"score":1,"resource":{"primary":{"URL":"https:\/\/publish.kne-publishing.com\/index.php\/IJM\/article\/view\/19885"},"secondary":[{"URL":"https:\/\/ijm.tums.ac.ir\/index.php\/ijm\/article\/view\/5505","label":"UNIVERSITY"}]},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,10,13]]},"references-count":0,"URL":"https:\/\/doi.org\/10.18502\/ijm.v17i5.19885","relation":{},"ISSN":["2008-4447","2008-3289"],"issn-type":[{"value":"2008-4447","type":"electronic"},{"value":"2008-3289","type":"print"}],"subject":[],"published":{"date-parts":[[2025,10,13]]}}}