Tinea — Clinical Case (Wikimedia Commons)

Diagnosis: Tinea

Tinea svenssoni. Clinical photograph sourced from Wikimedia Commons (Public domain). Attribution: Marko Mutanen, University of Oulu.

Clinical Presentation

Annular, erythematous plaques with raised, scaly, advancing border and central clearing. Tinea pedis: interdigital maceration, moccasin-type scaling. Tinea capitis: scaling alopecia, may have kerion (boggy inflammatory mass). Tinea unguium: thickened, discolored, dystrophic nails.

Clinical History

Risk factors: warm/humid environment, occlusive clothing, contact sports, shared facilities, immunosuppression, diabetes. Tinea capitis most common in prepubertal children. May be misdiagnosed as eczema — 'tinea incognito' when treated with topical steroids.

Treatment

Tinea corporis/cruris/pedis: topical antifungals (terbinafine, clotrimazole) × 2-4 weeks. Tinea capitis: ORAL antifungals required (terbinafine or griseofulvin × 4-8 weeks) — topical alone insufficient. Tinea unguium: oral terbinafine × 6-12 weeks.

Differential Diagnosis

Nummular eczema, Granuloma annulare, Psoriasis, Pityriasis rosea, Erythema migrans, Contact dermatitis

Key Learnings

KOH preparation is the essential bedside diagnostic test. Tinea capitis always requires systemic antifungals — topical cannot penetrate the hair follicle. 'Tinea incognito' occurs when fungal infections are treated with topical steroids, masking the typical appearance.

Tags: tinea, dermatophyte, fungal, ringworm, infection