Etiology

  • Dermatophytes: Trichophyton, Microsporum, Epidermophyton

  • Risk factors: sweating, occlusion, immunosuppression

Pathogenesis

  • Fungi invade keratinized tissue (stratum corneum)

  • Spread in warm, moist environments

Clinical Features

  • Ring-shaped scaly patches with raised borders (“ringworm”)

  • Tinea pedis: interdigital scaling

  • Tinea capitis: alopecia + black dots

  • KOH prep: hyphae

Treatment

  • Topical antifungals (clotrimazole, terbinafine)

  • Oral antifungals for scalp or nails (terbinafine, itraconazole)

  • Keep area dry