Clinical and Mycological Profiles of Chronic and Recalcitrant Dermatophytosis: Türkiye, 2022-2024.

Murat Durdu, Hazal Kandemir, Ayşe Sultan Karakoyun, Pavlína Lysková, Daniela Kolarczyková, Oğuzhan Bingöl, Yasemin Erdem, Funda Aktürk-Gözel, Özlem Su-Küçük, Melisa Özay, Aslan Yürekli, İlayda Muslu, İsa An, Sinan Özçelik, Tuğba Falay-Gür, Tuğba Tehçi, Abdullah Demirbaş, Gözde Ulutaş-Demirbaş, Tuğba Atak, Kaan Taşolar, Büşra Acar-Mantar, Mehmet Kamil Mülayim, Rebiay Kıran, Ayşe Tülin Mansur, İrem Yanatma, Sertaç Sever, Yeşim Yayla-Öztürk, Selami Aykut Temiz, Rabia Öztaş-Kara, Fatma Uzun, Ferit Kuşçu, Gonca Erköse-Genç, Zayre Erturan, Sybren de Hoog, Vit Hubka, Macit Ilkit

Journal: Mycopathologia 2026;191(2):34

PMID: 41706238

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Abstract

This study investigated the treatment outcomes of 91 patients with chronic and recalcitrant dermatophytosis from 20 hospitals in Türkiye between June 2022 and March 2024, as well as the in vitro antifungal susceptibility and squalene epoxidase (SQLE) substitution profiles of the dermatophytes obtained from these patients. Molecular identification by sequencing 91 isolates, revealed 76 Trichophyton mentagrophytes ITS genotype VIII (TmVIII; also known as T. indotineae) isolates, 13 Trichophyton rubrum, one Trichophyton tonsurans, and one Microsporum canis. The Phe397Leu substitution predominated in the SQLE, and Tyr414His co-occurred in nine TmVIII isolates. Five novel substitutions were observed in TmVIII. Among 13 T. rubrum isolates, three showed different SQLE substitution patterns compared to the wild-type strain. EUCAST antifungal susceptibility testing revealed high minimum inhibitory concentrations (MICs) for terbinafine (TRB) (> 0.25 mg/L) and for fluconazole (FLZ) (≥ 16 mg/L), indicating resistance in most TmVIII isolates. Of the 91 patients, 83 responded to FLZ, itraconazole (ITZ), TRB, or voriconazole-based regimens. While adjunct therapy with FLZ and resveratrol (RES) led to improvement in 28/29 patients despite their high in vitro inhibition concentrations, ITZ and curcumin (CUR) therapy was successful in 3/3 patients. However, the in vitro efficiency of CUR could not be evaluated. These findings highlight the local occurrence of specific SQLE substitutions, underscore the importance of EUCAST MIC testing combined with SQLE sequencing for surveillance, and support further evaluation of RES and CUR as an adjunct in TRB-resistant TmVIII.

Address: Department of Dermatology, Dr. Turgut Noyan Application and Research Center, Başkent University, Adana, Turkey.; Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands.; Department of Environmental Biology, Institute of Environmental Sciences (CML), Leiden University, Leiden, the Netherlands.; Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey.; Department of Medical Microbiology Prague and Kladno, Public Health Institute in Ústí Nad Labem, Prague, Czech Republic.; Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic.; Laboratory of Fungal Genetics and Metabolism, Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic.; Department of Dermatology and Venereology, İstanbul Faculty of Medicine, İstanbul University, Istanbul, Turkey.; Department of Dermatology and Venereology, School of Medicine, Bezmialem Vakıf University, Istanbul, Turkey.; Training and Research Hospital Dermatology Department, Muğla Sıtkı Koçman University, Muğla, Turkey.; Department of Dermatology, Şanlıurfa Training and Research Hospital, Şanlıurfa, Turkey.; Private Dermatology Clinic, Istanbul, Turkey.; Department of Dermatology, University of Health Sciences -Adana Health Practice and Research Center, Adana, Turkey.; Department of Dermatology, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey.; Department of Dermatology, Kocaeli City Hospital, Kocaeli, Turkey.; Ministry of Health Islahiye State Hospital, Dermatology Clinic, Gaziantep, Turkey.; Private Sular Academy Hospital, Dermatology Clinic, Kahramanmaraş, Turkey.; Bartın State Hospital, Dermatology Clinic, Bartın, Turkey.; Faculty of Medicine Department of Dermatology, Sütçü İmam University, Kahramanmaraş, Turkey.; Academic Hospital, Dermatology Clinic, Istanbul, Turkey.; Fethiye State Hospital, Dermatology Clinic, Muğla, Turkey.; Department of Dermatology, Avicenna Umut Hospital, Istanbul, Turkey.; Private Olimpos Hospital, Dermatology Clinic, Antalya, Turkey.; Department of Dermatology, Necmettin Erbakan University Medical Faculty, Konya, Turkey.; Sakarya Education and Research Hospital, Dermatology Clinic, Sakarya, Turkey.; Gemlik State Hospital, Dermatology Clinic, Bursa, Turkey.; Department of Infectious Diseases and Clinical Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey.; Department of Medical Microbiology, İstanbul Faculty of Medicine, İstanbul University, Istanbul, Turkey.; Center of Expertise in Mycology of Radboud University Medical Center/Canisius Wilhelmina Hospital, Nijmegen, the Netherlands.; Foundation Atlas of Clinical Fungi, Hilversum, the Netherlands.; Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey. [email protected].

DOI: 10.1007/s11046-026-01058-5

MeSH Terms: Humans, Antifungal Agents, Tinea, Microbial Sensitivity Tests, Female, Male, Middle Aged, Adult, Arthrodermataceae, Genotype, Aged, Squalene Monooxygenase, Drug Resistance, Fungal, Chronic Disease, Young Adult, Treatment Outcome, Adolescent, Trichophyton, Microsporum