A 26-year-old man presents with an annular scaly plaque over the groin with a raised, vesicular advancing edge and central clearing. KOH mount of the scale shows branching septate hyphae. Which organism is the most common cause of this presentation in India?

• A Trichophyton mentagrophytes
• B Microsporum audouinii
• C Epidermophyton floccosum
• D Trichophyton rubrum ✓

Explanation

Trichophyton rubrum is the most common dermatophyte isolated from tinea corporis, tinea cruris, tinea pedis and onychomycosis worldwide, including India. It produces a downy white colony with a red wine reverse pigment on culture. Microsporum audouinii is an anthropophilic cause of epidemic tinea capitis in children, Epidermophyton floccosum involves skin and nails but never hair, and T. mentagrophytes is zoophilic and causes more inflammatory lesions.

Reference: Rook's Textbook of Dermatology, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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