{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,4]],"date-time":"2026-11-04T03:53:39Z","timestamp":1793764419216,"version":"4.6.1"},"reference-count":21,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,10,11]],"date-time":"2022-10-11T00:00:00Z","timestamp":1665446400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Higher Education and Scientific Research of Tunisia"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background: Actually, no data on the prevalence of plasmid colistin resistance in Tunisia are available among clinical bacteria. Objectives: This study aimed to investigate the current epidemiology of colistin resistance and the spread of the mcr gene in clinical Gram-negative bacteria (GNB) isolated from six Tunisian university hospitals. Methods: A total of 836 GNB strains were inoculated on COL-R agar plates with selective screening agar for the isolation of GNB resistant to colistin. For the selected isolates, mcr genes, beta-lactamases associated-resistance genes and molecular characterisation were screened by PCRs and sequencing. Results: Colistin-resistance was detected in 5.02% (42\/836) of the isolates and colistin-resistant isolates harboured an ESBL (blaCTX-M-15) and\/or a carbapenemase (blaOXA-48, blaVIM) encoding gene in 45.2% of the cases. The mcr-1 gene was detected in four E. coli isolates (0.59%) causing urinary tract infections and all these isolates also contained the blaTEM-1 gene. The blaCTX-M-15 gene was detected in three isolates that also carried the IncY and IncFIB replicons. The genetic environment surrounding the mcr-carrying plasmid indicated the presence of pap-2 gene upstream mcr-1 resistance marker with unusual missing of ISApl1 insertion sequence. The Conclusions: This study reports the first description of the mcr-1 gene among clinical E. coli isolates in Tunisia and provides an incentive to conduct routine colistin susceptibility testing in GNB clinical isolates.<\/jats:p>","DOI":"10.3390\/antibiotics11101390","type":"journal-article","created":{"date-parts":[[2022,10,11]],"date-time":"2022-10-11T22:18:13Z","timestamp":1665526693000},"page":"1390","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Tunisian Multicenter Study on the Prevalence of Colistin Resistance in Clinical Isolates of Gram Negative Bacilli: Emergence of Escherichia coli Harbouring the mcr-1 Gene"],"prefix":"10.3390","volume":"11","author":[{"given":"Sana","family":"Ferjani","sequence":"first","affiliation":[{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR99ES09, Tunis Rue Djebal Lakhdar 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0241-2191","authenticated-orcid":false,"given":"Elaa","family":"Maamar","sequence":"additional","affiliation":[{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR99ES09, Tunis Rue Djebal Lakhdar 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Asma","family":"Ferjani","sequence":"additional","affiliation":[{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR99ES09, Tunis Rue Djebal Lakhdar 1006, Tunisia"},{"name":"Charles Nicolle Hospital, Laboratory of Microbiology, Boulevard 9 April, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3312-8265","authenticated-orcid":false,"given":"Khaoula","family":"Meftah","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Children\u2019s Hospital of Tunis, Boulevard 9 April, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5363-4144","authenticated-orcid":false,"given":"Hager","family":"Battikh","sequence":"additional","affiliation":[{"name":"Microbiology Laboratory, Rabta University Hospital, Rue Jabbari, Tunis 1007, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0841-6532","authenticated-orcid":false,"given":"Besma","family":"Mnif","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Habib Bourguiba University Hospital, Route de l\u2019Ain, Sfax 3000, Tunisia"},{"name":"Research Laboratory for Microorganisms and Human Disease, University of Sfax, Avenue Majida Boulila, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manel","family":"Hamdoun","sequence":"additional","affiliation":[{"name":"Aziza Othmana Hospital, Laboratoire de Microbiologie-Biochimie, Bab Menara Tunis 1008, Tunisia"},{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR16SP01, Tunis Rue Djebal Lakhdar 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yosra","family":"Chebbi","sequence":"additional","affiliation":[{"name":"National Bone Marrow Transplant Center, Laboratory Ward, Tunis Rue Djebal Lakhdar 1006, Tunisia"},{"name":"Faculty of Medicine of Tunis, Tunis El Manar University, LR18ES39, Tunis Rue Djebal Lakhdar 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lamia","family":"Kanzari","sequence":"additional","affiliation":[{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR99ES09, Tunis Rue Djebal Lakhdar 1006, Tunisia"},{"name":"Charles Nicolle Hospital, Laboratory of Microbiology, Boulevard 9 April, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wafa","family":"Achour","sequence":"additional","affiliation":[{"name":"National Bone Marrow Transplant Center, Laboratory Ward, Tunis Rue Djebal Lakhdar 1006, Tunisia"},{"name":"Faculty of Medicine of Tunis, Tunis El Manar University, LR18ES39, Tunis Rue Djebal Lakhdar 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olfa","family":"Bahri","sequence":"additional","affiliation":[{"name":"Aziza Othmana Hospital, Laboratoire de Microbiologie-Biochimie, Bab Menara Tunis 1008, Tunisia"},{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR16SP01, Tunis Rue Djebal Lakhdar 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adenene","family":"Hammami","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Habib Bourguiba University Hospital, Route de l\u2019Ain, Sfax 3000, Tunisia"},{"name":"Research Laboratory for Microorganisms and Human Disease, University of Sfax, Avenue Majida Boulila, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meriam","family":"Zribi","sequence":"additional","affiliation":[{"name":"Microbiology Laboratory, Rabta University Hospital, Rue Jabbari, Tunis 1007, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanen","family":"Smaoui","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Children\u2019s Hospital of Tunis, Boulevard 9 April, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6590-2406","authenticated-orcid":false,"given":"Ilhem Boutiba-Ben","family":"Boubaker","sequence":"additional","affiliation":[{"name":"Faculty of Medicine of Tunis, University of Tunis El Manar, LR99ES09, Tunis Rue Djebal Lakhdar 1006, Tunisia"},{"name":"Charles Nicolle Hospital, Laboratory of Microbiology, Boulevard 9 April, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1016\/j.ijantimicag.2018.08.022","article-title":"Epidemiology and Molecular Characterisation of Colistin-Resistant Klebsiella pneumoniae Isolates from Immunocompromised Patients in Tunisia","volume":"52","author":"Tanfous","year":"2018","journal-title":"Int. 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