Tinea corporis is a superficial dermatophyte infection of glabrous skin caused by Trichophyton, Microsporum, or Epidermophyton species. It presents as annular erythematous plaques with advancing scaly borders and central clearing. Diagnosis is clinical supported by KOH microscopy. Topical antifungals are effective for limited disease; oral therapy is indicated for extensive, inflammatory (Majocchi granuloma), hair-bearing areas, or refractory cases. Consider zoonotic sources (pets, livestock) and fomite transmission; decontamination and contact management are essential.
Epidemiology and Transmission
- All ages; common in children and athletes (wrestlers—tinea corporis gladiatorum).
- Transmission via infected humans, animals (cats, dogs, cattle; M. canis), or fomites (shared gear, mats, clothing).
Clinical Features
- Annular plaques with active scaly/raised border; central clearing; pruritic.
- Variants:
- Tinea corporis gladiatorum: face/neck/arms in wrestlers; often T. tonsurans; frequent recurrences.
- Majocchi granuloma: perifollicular papules/nodules due to follicular invasion—often after topical steroids or shaving; requires systemic therapy.
- Tinea imbricata (T. concentricum): concentric rings in tropical regions.
- Tinea incognito: atypical due to prior topical steroids/calcineurin inhibitors—less scaly, more extensive; suspect with refractory “eczema.”
Differential Diagnosis
- Nummular eczema, psoriasis, pityriasis rosea, granuloma annulare, subacute cutaneous lupus, erythema annulare centrifugum, Lyme erythema migrans.
Diagnosis
- KOH prep from active border shows septate hyphae.
- Fungal culture/PCR for species ID in refractory/inflammatory cases or epidemiologic reasons.
- Dermoscopy: peripheral scaling, dotted vessels; not diagnostic alone.
Management
- Topical antifungals (limited disease)
- Terbinafine 1% qd for 1–2 weeks or azoles (clotrimazole, miconazole, ketoconazole) bid for 2–4 weeks; continue 1–2 weeks after clearing.
- Avoid steroid–antifungal combination creams; risk tinea incognito and recurrence.
- Oral antifungals (extensive, follicular involvement, hair-bearing areas, immunosuppressed, or failed topicals)
- Terbinafine 250 mg daily for 2–4 weeks.
- Itraconazole 200 mg daily for 1–2 weeks (or 100 mg bid).
- Fluconazole 150–200 mg weekly for 2–6 weeks.
- Griseofulvin for Microsporum species in some settings.
- Monitor interactions and hepatic function where appropriate.
- Source control and prevention
- Screen/treat household contacts with lesions.
- Veterinary evaluation and treatment for symptomatic pets; clean bedding and grooming tools.
- Decontaminate sports gear/mats; institute team protocols for wrestlers (skin checks, exclusion until treated 72 hours with systemic therapy for gladiatorum; cover lesions).
- Special situations
- Majocchi granuloma: requires oral antifungals 4–6+ weeks; avoid further steroids; consider biopsy if unclear.
- Tinea faciei: use non-steroidal antifungals; extra caution to avoid tinea incognito.
- Tinea in skin of color: higher PIH risk—treat early and avoid steroid combinations.
References (recent guidelines and key reviews)
- Superficial dermatophyte infections: diagnosis and treatment guidelines, 2022–2024.
- Athlete-focused protocols for tinea gladiatorum, 2021–2024.
- Steroid-modified tinea (tinea incognito) reviews, 2022–2024.