{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T21:51:20Z","timestamp":1790718680094,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,9,27]],"date-time":"2022-09-27T00:00:00Z","timestamp":1664236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Academy of Dermatology and Venereology","award":["PPRC-2019-20"],"award-info":[{"award-number":["PPRC-2019-20"]}]},{"name":"University of Lausanne (SKINTEGRITY.CH collaborative research program)","award":["PPRC-2019-20"],"award-info":[{"award-number":["PPRC-2019-20"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JoF"],"abstract":"<jats:p>Rapid and reliable fungal identification is crucial to delineate infectious diseases, and to establish appropriate treatment for onychomycosis. Compared to conventional diagnostic methods, molecular techniques are faster and feature higher accuracy in fungal identification. However, in current clinical practice, molecular mycology is not widely available, and its practical applicability is still under discussion. This study summarizes the results of 16,094 consecutive nail specimens with clinical suspicion of onychomycosis. We performed PCR\/sequencing on all primary nail specimens for which conventional mycological diagnostics remained inconclusive. In specimens with a positive direct microscopy but negative or contaminated culture, molecular mycology proved superior and specified a fungal agent in 65% (587\/898). In 75% (443\/587), the identified pathogen was a dermatophyte. Positive cultures for dermatophytes, yeasts and non-dermatophyte molds (NDMs) were concordant with primary-specimen-DNA PCR\/sequencing in 83% (10\/12), 34% (22\/65) and 45% (76\/169), respectively. Among NDMs, agreement was high for Fusarium spp. (32\/40; 80%), but low for Penicillium spp. (5\/25; 20%) and Alternaria spp. (1\/20; 5%). This study underlines the improvement in diagnostic yield by fungal primary-specimen-DNA PCR\/sequencing in the event of a negative or contaminated culture, as well as its significance for the diagnosis of dermatophyte and non-dermatophyte onychomycosis. Molecular mycology methods like PCR and DNA sequencing should complement conventional diagnostics in cases of equivocal findings, suspected NDM onychomycosis or treatment-resistant nail pathologies.<\/jats:p>","DOI":"10.3390\/jof8101019","type":"journal-article","created":{"date-parts":[[2022,9,28]],"date-time":"2022-09-28T01:51:49Z","timestamp":1664329909000},"page":"1019","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Identification of Dermatophyte and Non-Dermatophyte Agents in Onychomycosis by PCR and DNA Sequencing\u2014A Retrospective Comparison of Diagnostic Tools"],"prefix":"10.3390","volume":"8","author":[{"given":"Isabella","family":"Pospischil","sequence":"first","affiliation":[{"name":"Department of Dermatology, Kepler University Hospital, Johannes Kepler University Linz, 4020 Linz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlotte","family":"Reinhardt","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Kepler University Hospital, Johannes Kepler University Linz, 4020 Linz, Austria"},{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olympia","family":"Bontems","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karine","family":"Salamin","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marina","family":"Fratti","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7020-0751","authenticated-orcid":false,"given":"Gabriela","family":"Blanchard","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yun-Tsan","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7003-9512","authenticated-orcid":false,"given":"Helga","family":"Wagner","sequence":"additional","affiliation":[{"name":"Center for Clinical Studies (CCS Linz), Johannes Kepler University Linz, 4020 Linz, Austria"},{"name":"Institute of Applied Statistics, Johannes Kepler University Linz, 4020 Linz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philipp","family":"Hermann","sequence":"additional","affiliation":[{"name":"Center for Clinical Studies (CCS Linz), Johannes Kepler University Linz, 4020 Linz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michel","family":"Monod","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfram","family":"Hoetzenecker","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Kepler University Hospital, Johannes Kepler University Linz, 4020 Linz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5478-8735","authenticated-orcid":false,"given":"Emmanuella","family":"Guenova","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Lausanne University Hospital (CHUV) and the Faculty of Biology and Medicine, University of Lausanne, 1007 Lausanne, Switzerland"},{"name":"Department of Dermatology, University Hospital Zurich and the University of Zurich, 8091 Zurich, Switzerland"},{"name":"Department of Dermatology, Hospital 12 de Octubre, Medical School, University Complutense, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1480","DOI":"10.1111\/jdv.12323","article-title":"The prevalence of onychomycosis in the global population\u2014A literature study","volume":"28","author":"Sigurgeirsson","year":"2014","journal-title":"J. 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Assoc."}],"container-title":["Journal of Fungi"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2309-608X\/8\/10\/1019\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:40:37Z","timestamp":1760143237000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2309-608X\/8\/10\/1019"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9,27]]},"references-count":46,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2022,10]]}},"alternative-id":["jof8101019"],"URL":"https:\/\/doi.org\/10.3390\/jof8101019","relation":{},"ISSN":["2309-608X"],"issn-type":[{"value":"2309-608X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,9,27]]}}}