{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T21:16:52Z","timestamp":1790975812624,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,16]],"date-time":"2025-01-16T00:00:00Z","timestamp":1736985600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Up to one-quarter of the United States population is affected by tinea pedis (athlete\u2019s foot). Tinea pedis of the web space (interdigital tinea pedis) is a common clinical presentation causing skin macerations and fissures. A \u201cdermatophytosis complex\u201d (i.e., concomitant bacterial colonization) further complicates treatment. Here, we examined records of 14,429 skin specimens taken from the feet of dermatology and podiatry outpatients over a 4.6-year period; all specimens were subjected to multiplex qPCR diagnosis for the detection of dermatophytes, Candida, Corynebacterium minutissimum, Pseudomonas and Staphylococcus aureus. A literature search was conducted to review the reported prevalence of fungal and bacterial agents. In both interdigital and plantar foot specimens, dermatophytes (33.3\u201333.8%) and S. aureus (24.3\u201325%) were found to be the predominate pathogens. In the interdigital space, a higher prevalence of C. minutissimum (15.7% vs. 7.9%) and Pseudomonas (23.5% vs. 9.6%) was found. The detection of Pseudomonas was more likely to be observed in the presence of Candida, reflecting a higher risk of mixed infection. In dermatophyte-positive specimens, the \u201cdermatophytosis complex\u201d variant was observed at 45.5% (SD: 2.3). An analysis of patient characteristics showed male patients exhibiting higher likelihoods for dermatophyte, C. minutissimum, Pseudomonas and S. aureus detections. The elderly were disproportionately infected with Candida. In children, an S. aureus detection was more common, which could be attributed to impetigo. The recent literature lacks reporting on concomitant bacterial colonization in tinea pedis patients, likely due to the reliance on fungal culture supplemented with antibiotics. Geographical variation has been identified in the detection of the Trichophyton mentagrophytes complex. In conclusion, PCR diagnosis serves as a valuable tool for the management of tinea pedis. An accurate and timely detection of fungal pathogens and concomitant bacterial colonization can better inform healthcare providers of appropriate treatment selection.<\/jats:p>","DOI":"10.3390\/microorganisms13010184","type":"journal-article","created":{"date-parts":[[2025,1,16]],"date-time":"2025-01-16T10:44:23Z","timestamp":1737024263000},"page":"184","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Interdigital and Plantar Foot Infections: A Retrospective Analysis of Molecularly Diagnosed Specimens in the United States and a Literature Review"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8664-7723","authenticated-orcid":false,"given":"Aditya K.","family":"Gupta","sequence":"first","affiliation":[{"name":"Division of Dermatology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 3H2, Canada"},{"name":"Mediprobe Research Inc., London, ON N5X 2P1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9359-9750","authenticated-orcid":false,"given":"Tong","family":"Wang","sequence":"additional","affiliation":[{"name":"Mediprobe Research Inc., London, ON N5X 2P1, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sara A.","family":"Lincoln","sequence":"additional","affiliation":[{"name":"Bako Diagnostics, Alpharetta, GA 30005, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5560-1151","authenticated-orcid":false,"given":"Wayne L.","family":"Bakotic","sequence":"additional","affiliation":[{"name":"Bako Diagnostics, Alpharetta, GA 30005, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e13787","DOI":"10.1111\/myc.13787","article-title":"Global, Regional, and National Burden of Fungal Skin Diseases in 204 Countries and Territories from 1990 to 2021: An Analysis of the Global Burden of Disease Study 2021","volume":"67","author":"Qin","year":"2024","journal-title":"Mycoses"},{"key":"ref_2","first-page":"s42","article-title":"Identifying Signs of Tinea Pedis: A Key to Understanding Clinical Variables","volume":"14","author":"Canavan","year":"2015","journal-title":"J. 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