Which genus is commonly implicated in causing tinea cruris by infecting keratinized skin?

Which genus is commonly implicated in causing tinea cruris by infecting keratinized skin?

• A. Trichophyton
• B. Malassezia
• C. Aspergillus
• D. Candida

Answer: (A)

Infections of keratinized skin by fungi are caused by dermatophytes, which specialize in invading the outer, keratin-rich layers of the skin, hair, and nails. For tinea cruris, the genus most commonly responsible is Trichophyton. These organisms secrete keratinases that break down keratin, allowing them to colonize the stratum corneum and produce the characteristic pruritic, scaly, ring-shaped lesions in the groin area. Other fungi listed—Malassezia causes tinea versicolor, Candida tends to cause mucocutaneous candidiasis and intertrigo in moist areas, and Aspergillus is typically linked to environmental or invasive infections rather than superficial dermatophyte infections. Therefore, Trichophyton best fits as the cause of tinea cruris by infecting keratinized skin.

Infections of keratinized skin by fungi are caused by dermatophytes, which specialize in invading the outer, keratin-rich layers of the skin, hair, and nails. For tinea cruris, the genus most commonly responsible is Trichophyton. These organisms secrete keratinases that break down keratin, allowing them to colonize the stratum corneum and produce the characteristic pruritic, scaly, ring-shaped lesions in the groin area. Other fungi listed—Malassezia causes tinea versicolor, Candida tends to cause mucocutaneous candidiasis and intertrigo in moist areas, and Aspergillus is typically linked to environmental or invasive infections rather than superficial dermatophyte infections. Therefore, Trichophyton best fits as the cause of tinea cruris by infecting keratinized skin.