dermatophyten

Dermatophyten, commonly known as dermatophytes, are a group of keratinophilic fungi that infect keratinized tissues such as skin, hair, and nails. They belong primarily to the genera Trichophyton, Microsporum and Epidermophyton, and are classified within the phyla Ascomycota and, in some cases, Basidiomycota. These organisms are adapted to utilize keratin as a nutrient source, producing keratinases that degrade the protein matrix of the outer skin layers, facilitating colonization and lesion formation.

Infections caused by dermatophytes are collectively termed dermatophytoses or tinea, with specific names reflecting the body site involved (e.g., tinea corporis for the body, tinea pedis for the foot, tinea capitis for the scalp). Transmission occurs through direct contact with infected hosts, contaminated fomites, or animal reservoirs. The prevalence of dermatophyte infections is high worldwide, particularly in warm, humid climates and among populations with close animal contact or compromised immune defenses.

Clinical manifestations range from superficial, scaly erythema to more extensive erosions, depending on the species involved and the host’s immune response. Diagnosis is based on clinical presentation, microscopic examination of skin scrapings with potassium hydroxide, and culture on specialized media. Molecular methods such as PCR are increasingly used for rapid species identification.

Therapeutic management includes topical antifungal agents for localized disease and systemic therapy (e.g., terbinafine, itraconazole) for extensive or refractory cases. Preventive measures focus on hygiene, avoiding shared personal items, and controlling infection in animal carriers. Ongoing research aims to elucidate resistance mechanisms and develop novel antifungal compounds.