{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T05:38:22Z","timestamp":1787981902345,"version":"build-2784847793"},"reference-count":38,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,8,8]],"date-time":"2024-08-08T00:00:00Z","timestamp":1723075200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Ministry of Health"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Background: The treatment of non-tuberculous mycobacterial (NTM) infections is challenging because of the difficulty in obtaining phenotypic (pDST) and\/or molecular (mDST) drug susceptibility testing and the need of a multi-drug regimen. Objectives: The objective was to describe the in vitro susceptibility patterns of various NTM species through an analysis of susceptibility results obtained on isolates collected between 2018 and 2023. Methods: Species identification and mutations in rrs or rrl genes (mDST) were identified by a line probe assay, while the pDST was performed by broth microdilution and interpreted according to CLSI criteria. Results: We analysed 337 isolates of NTM belonging to 15 species\/subspecies. The Mycobacterium avium complex (MAC) was the most common (62%); other species identified included M. gordonae (11%), M. kansasii (5%), the M. abscessus complex (8%), M. chelonae (6%), and M. fortuitum (2%). The results of pDST (claritromycin and amikacin) and mDST (rrl and rrs genes) on 66 NTM strains showed that while wild-type rrl and rrs occurred in 86.3% and 94% strains, respectively, the pDST showed 88% sensitivity for clarithromycin and 57.5% for amikacin. The main incongruity was observed for macrolides. Conclusions: Most NTM are likely to be susceptible to macrolides and aminoglycosides. The molecular identification of resistant genotypes is accurate and strongly recommended for optimal patient management.<\/jats:p>","DOI":"10.3390\/microorganisms12081615","type":"journal-article","created":{"date-parts":[[2024,8,8]],"date-time":"2024-08-08T07:01:25Z","timestamp":1723100485000},"page":"1615","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["The Drug Susceptibility of Non-Tuberculous Mycobacteria (NTM) in a Referral Hospital in Rome from 2018 to 2023"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6285-4368","authenticated-orcid":false,"given":"Antonio","family":"Mazzarelli","sequence":"first","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5369-0437","authenticated-orcid":false,"given":"Carla","family":"Nisii","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angela","family":"Cannas","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonella","family":"Vulcano","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3882-3996","authenticated-orcid":false,"given":"Barbara","family":"Bartolini","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica","family":"Turchi","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ornella","family":"Butera","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Rossi","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chiara","family":"De Giuli","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chiara","family":"Massimino","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chiara","family":"Stellitano","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valentina","family":"Antonelli","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivano","family":"Petriccione","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8182-5896","authenticated-orcid":false,"given":"Enrico","family":"Girardi","sequence":"additional","affiliation":[{"name":"Scientific Direction, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gina","family":"Gualano","sequence":"additional","affiliation":[{"name":"Respiratory Infectious Diseases Unit, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8184-6291","authenticated-orcid":false,"given":"Fabrizio","family":"Palmieri","sequence":"additional","affiliation":[{"name":"Respiratory Infectious Diseases Unit, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2198-1947","authenticated-orcid":false,"given":"Carla","family":"Fontana","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Biorepository, National Institute for Infectious Diseases, INMI \u201cLazzaro Spallanzani\u201d, IRCCS, Via Portuense 292, 00149 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"245","DOI":"10.3947\/ic.2019.51.3.245","article-title":"Treatment of extrapulmonary nontuberculous mycobacterial diseases","volume":"51","author":"Wi","year":"2019","journal-title":"Infect. 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