Background: Chronic dermatophytosis is an increasingly prevalent and therapeutically challenging condition in India. Rising cases of treatment failure and relapse have prompted concerns about antifungal resistance. Understanding the antifungal susceptibility patterns of dermatophytes is essential to guide effective therapy.

Objectives: To isolate and identify dermatophytes from patients with chronic tinea infections and determine their antifungal susceptibility profiles.

Materials and Methods: This prospective study was conducted over a one-year period (July 2023 to June 2024) at a tertiary care teaching hospital in Central India. Clinical specimens (skin, hair, and nail samples) from patients with chronic dermatophytosis (defined as tinea infection persisting for more than six months) were processed by direct microscopy and cultured on Sabouraud Dextrose Agar with and without cycloheximide. Dermatophytes were identified using standard morphological methods. Antifungal susceptibility testing (AFST) was performed using the CLSI M38-A2 broth microdilution method for terbinafine, itraconazole, griseofulvin, fluconazole, ketoconazole, and voriconazole.

Results: Out of 220 clinical samples, 158 (71.8%) were positive for dermatophytes. Trichophyton mentagrophytes complex (58.2%) was the predominant isolate, followed by T. rubrum (28.4%). High minimum inhibitory concentrations (MICs) were observed for griseofulvin and fluconazole, whereas terbinafine and itraconazole showed better in vitro activity. A concerning proportion of isolates showed reduced susceptibility to multiple antifungal agents, particularly terbinafine.

Conclusion: The study highlights a shift in the epidemiology of chronic dermatophytosis, with dominance of T. mentagrophytes complex and emerging antifungal resistance. Regular surveillance of antifungal susceptibility and judicious antifungal use are crucial for effective management of chronic tinea infections.