Tinea Corporis

Diagnosis: Tinea Corporis

Annular erythematous scaling patch with an active border composed of papules, vesicles and crusts.

Clinical Presentation

Tinea Corporis Annular erythematous scaling patch with an active border composed of papules, vesicles and crusts.

Clinical History

Annular, erythematous, scaly plaque with raised border and central clearing. Contact with animals, affected individuals, or contaminated fomites. Prior topical steroid use (tinea incognito).

Treatment

Topical: terbinafine 1% cream, clotrimazole, miconazole BID × 2-4 weeks. Systemic (extensive/recalcitrant): terbinafine 250mg/day or itraconazole. Treat source of infection.

Differential Diagnosis

• Nummular eczema • Granuloma annulare • Psoriasis • Pityriasis rosea • Contact dermatitis • Erythema annulare centrifugum • Subacute cutaneous lupus

Key Learnings

• Caused by dermatophytes: Trichophyton, Microsporum, Epidermophyton • KOH preparation is the essential first-line diagnostic test — hyphae confirm diagnosis • Annular, scaly plaque with advancing border and central clearing is classic • Tinea incognito: atypical presentation due to prior topical corticosteroid use — always do KOH • Majocchi granuloma: dermatophyte folliculitis, often from shaving — requires systemic antifungals • Zoophilic species (M. canis from cats/dogs) tend to cause more inflammatory reactions • Topical antifungals sufficient for limited disease; systemic needed for extensive, follicular, or recalcitrant

Tags: dermatology, kodachrome, Tinea Corporis