Epidermophyton

Epidermophyton is a genus of keratinophilic fungi in the family Arthrodermataceae. Members are dermatophytes that invade keratinized tissues such as skin and nails. The genus includes several species, of which Epidermophyton floccosum is the best known for causing human disease. Transmission occurs through direct contact with infected skin or nails or via contaminated objects; infections are common in warm, moist environments and can be chronic if untreated.

Morphology and identification: Epidermophyton species are distinguished by lacking microconidia and by producing large, smooth-walled macroconidia that are club-shaped and often multiseptate. These features aid identification in culture, where colonies can appear slow-growing and may be yellowish or pale before maturing.

Clinical disease: E. floccosum causes tinea pedis (athlete’s foot), tinea cruris (jock itch), and tinea corporis. It does not typically invade hair. Nails may be affected in some cases.

Diagnosis: Diagnosis relies on microscopy of skin, hair, or nail scrapings showing hyphae, and culture on fungal media that yields characteristic macroconidia. Molecular methods are increasingly used.

Treatment and prognosis: Most infections respond to topical antifungals such as terbinafine, itraconazole, or azoles; extensive or nail involvement may require systemic therapy for several weeks to months. Prognosis is generally good with adherence to treatment. Prevention includes good hygiene and avoiding sharing contaminated objects.