Which of the following dermatophytes is anthropophilic and most commonly causes tinea corporis in humans?

Explanation

## Anthropophilic Dermatophytes **Key Point:** Anthropophilic dermatophytes have adapted to human skin and are the most common cause of dermatophytosis worldwide. They cause chronic infections with minimal inflammation. **High-Yield:** Trichophyton rubrum is the single most common dermatophyte globally, responsible for approximately 70% of all dermatophyte infections, particularly tinea corporis, tinea pedis, and tinea unguium. ## Classification of Dermatophytes by Host Preference | Category | Characteristics | Examples | Clinical Pattern | |----------|-----------------|----------|------------------| | **Anthropophilic** | Adapted to humans; chronic, minimally inflammatory | T. rubrum, T. mentagrophytes var. mentagrophytes, E. floccosum | Chronic, indolent | | **Zoophilic** | Animal-adapted; acute, highly inflammatory when infect humans | M. canis, T. mentagrophytes var. quinckeanum, T. verrucosum | Acute, severe inflammation | | **Geophilic** | Soil-dwelling; rare in humans; acute inflammation | T. mentagrophytes var. mentagrophytes (some strains), M. gypseum | Occupational exposure | **Clinical Pearl:** Anthropophilic species cause chronic infections because they have evolved to evade human immune responses. Zoophilic infections are typically more acute and inflammatory because the organism is not adapted to human skin. **Mnemonic — Common Anthropophilic Dermatophytes: "REM"** - **R** — Rubrum (T. rubrum) - **E** — Erinacei (T. erinacei) - **M** — Mentagrophytes var. mentagrophytes (T. mentagrophytes var. mentagrophytes) ## Why T. rubrum Dominates 1. Highly adapted to human keratinous tissues 2. Produces keratinolytic enzymes optimized for human skin pH and temperature 3. Minimal inflammatory response allows persistent colonization 4. Easily transmitted person-to-person 5. Resistant to many environmental stressors