{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:45:14Z","timestamp":1790729114261,"version":"4.1.0"},"reference-count":16,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,6,28]],"date-time":"2023-06-28T00:00:00Z","timestamp":1687910400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JoF"],"abstract":"<jats:p>Onychomycosis is a common nail infection. Terbinafine-resistant dermatophyte infections pose an emerging global public health concern, but few cases have been described in the United States. We retrospectively reviewed and characterized clinical, histopathological, and mycological features of patients with mycologically confirmed onychomycosis who failed oral terbinafine treatment for onychomycosis at a U.S. academic nail referral center and ascertained for terbinafine-resistant isolates. During 1 June 2022\u201331 January 2023 at Weill Cornell Medicine in New York City, USA, 96 patients with mycologically confirmed onychomycosis were treated with oral terbinafine. Among 64 patients with adequate follow-up, 36 had clinical or complete cure. Of 28 patients who failed treatment, 17 underwent terbinafine resistance testing. Trichophyton rubrum with terbinafine resistance-conferring mutations was isolated from two patients. Overall, terbinafine failures for onychomycosis were relatively common, with some cases associated with terbinafine-resistant T. rubrum infections. These findings underscore the need for a clinical awareness of this emerging problem and public health efforts to monitor and prevent spread. We highlight the importance of diagnostic testing and species identification for onychomycosis patients and the increasingly important role of fungal identification and susceptibility testing to guide therapy.<\/jats:p>","DOI":"10.3390\/jof9070710","type":"journal-article","created":{"date-parts":[[2023,6,29]],"date-time":"2023-06-29T01:43:13Z","timestamp":1688002993000},"page":"710","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Isolation of Terbinafine-Resistant Trichophyton\u00a0rubrum from Onychomycosis Patients Who Failed Treatment at an Academic Center in New York, United States"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5066-5057","authenticated-orcid":false,"given":"Jonathan K.","family":"Hwang","sequence":"first","affiliation":[{"name":"Weill Cornell Medicine, New York, NY 10021, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wayne L.","family":"Bakotic","sequence":"additional","affiliation":[{"name":"Bako Diagnostics, Alpharetta, GA 30005, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5054-7616","authenticated-orcid":false,"given":"Jeremy A. W.","family":"Gold","sequence":"additional","affiliation":[{"name":"Centers for Disease Control and Prevention, Atlanta, GA 30329, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cynthia M.","family":"Magro","sequence":"additional","affiliation":[{"name":"Weill Cornell Medicine, New York, NY 10021, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5913-9304","authenticated-orcid":false,"given":"Shari R.","family":"Lipner","sequence":"additional","affiliation":[{"name":"Weill Cornell Medicine, New York, NY 10021, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"835","DOI":"10.1016\/j.jaad.2018.03.062","article-title":"Onychomycosis: Clinical overview and diagnosis","volume":"80","author":"Lipner","year":"2019","journal-title":"J. Am. Acad. Dermatol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1933","DOI":"10.2147\/CCID.S362635","article-title":"Updated Perspectives on the Diagnosis and Management of Onychomycosis","volume":"15","author":"Falotico","year":"2022","journal-title":"Clin. Cosmet. Investig. Dermatol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"853","DOI":"10.1016\/j.jaad.2018.05.1260","article-title":"Onychomycosis: Treatment and prevention of recurrence","volume":"80","author":"Lipner","year":"2019","journal-title":"J. Am. Acad. Dermatol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1007\/s40257-020-00580-6","article-title":"The Growing Problem of Antifungal Resistance in Onychomycosis and Other Superficial Mycoses","volume":"22","author":"Gupta","year":"2021","journal-title":"Am. J. Clin. 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