Shifting nature of dermatophytosis and antifungal susceptibility – The proof we seek

Background: Approximately 20%–25% of people suffer from dermatophytosis worldwide. In India, this has significantly risen recently. Antifungal resistance is another major issue leading to chronic dermatophytosis. In this background, this study was done to isolate and identify the species of dermatophytes among acute, chronic and recurrent dermatophytosis and detect their antifungal susceptibility pattern. Materials and Methods: A total of 120 suspected dermatophytosis patients were subjected to KOH mount and culture. Antifungal susceptibility testing was performed on the isolates. Results: The mean age of dermatophytosis with chronic infection, recurrent infection, and acute infection was 38.52 years, 37.17 years, and 31.35 years, respectively. Females outnumbered males in chronic and recurrent dermatophytosis. Tinea corporis was the most common lesion observed. KOH mount was positive in 86 (72%) patients, whereas culture positive was noted in 68 (57%) patients. Trichophyton mentagrophytes (T. mentagrophytes) was the most common species, followed by Trichophyton rubrum (T. rubrum) and Trichophyton tonsurans (T. tonsurans) in all acute, chronic, and recurrent dermatophytosis. Minimum inhibitory concentration (MIC) for griseofulvin was 0.12–1 μg/ml for T. mentagrophytes and 1–8 μg/ml for T. rubrum . MIC for fluconazole was 0.5–128 μg/ml for T. mentagrophytes and 0.5–64 μg/ml for T. rubrum . MIC for itraconazole was 0.125–0.5 μg/ml for T. mentagrophytes and 0.03–1 μg/ml for T. rubrum . MIC for terbinafine was 0.005–0.125 µg/ml for T. mentagrophytes and 0.25–0.5 μg/ml for T. rubrum . Conclusion: T. mentagrophytes emerged as the predominant species across all clinical presentations. The observed rise in MICs, especially for fluconazole and griseofulvin, suggests emerging antifungal resistance. Routine species identification and antifungal susceptibility testing are critical for effective dermatophytosis management.