Diagnosis: Tinea Faciei

Periodic acid-Schiff stain (PAS) revealed positive hyphae. The patient was treated with daily topical antifungal cream. He reported complete improvement 2 weeks after starting treatment, and did not require oral antifungals.

Tinea faciei is a fungal infection that is limited to the face. The severity of infection often depends on the species of dermatophyte and the host’s immune response. Typically, lesions appear 1-3 weeks after skin invasion and present in an annular pattern with central clearing, although other shapes may also form.

Pustules in the border and scale are often present. Patients who have used topical corticosteroid treatments may not have any scale. This is often referred to as tinea incognito and can make the diagnosis more challenging.

Tinea faciei is more commonly seen in climates with hot temperatures or humid conditions. It often occurs in children, and in adults aged 20-40 years, and is frequently acquired from pets in the home. In North America, Trichophyton tonsurans is the most common pathogen.

The differential diagnosis includes seborrheic dermatitis, lupus vulgaris, and acne rosacea. A KOH (potassium hydroxide) test will often reveal hyphae. The scraping should be performed from the border of the lesions where the more severe inflammatory reaction occurs and the most fungal elements are present. A culture may also be performed, but takes 3-4 weeks for results. Histology will often reveal fungal hyphae that are PAS positive.

Most cases respond to topical antifungals, such as topical ciclopirox, terbinafine, or azoles. Systemic antifungals may be used if the lesions do not respond to treatment.