Is it a fungus?

Abstract

Superficial mycoses are believed to affect 20% to 25% of the worlds population and its incidence continues to increase. They are mainly caused by dermatophytes, which are fungi that require keratin for their growth. Skin lesions produced by these fungi are named dermatomycosis, dermatophytosis, ringworm or tinea. In Family Medicine, the clinician often has to deal with questions such as: «Dr., some weird spots have appeared in my skin, is it a fungus». Frequently it is difficult to decide whether it is appropriate to initiate systemic therapy, particularly in higher risk patients, such as the polimedicated, the immunodepressed, the diabetics and the children. This article intends to review dermatophyte infections, focusing especially on their therapeutic management. Tinea is generally classified according to its anatomic location: tinea capitis is located on the scalp, tinea pedis on the feet, tinea corporis on the body, tinea cruris on the groin, and tinea unguium on the nails. A thorough clinical examination is the primary and most important step to diagnose a dermatophyte infection. Yet, it can be established using potassium hydroxide microscopy, fungal culture, Woods lamp examination or histologic examination. Samples should be taken for microscopy and culture in severe or extensive skin fungal infections, when oral treatment is being considered, when skin infections are refractory to initial treatment, or when the diagnosis is uncertain. Although topical treatment is enough in the majority of dermatomycosis, oral antifungals are recommended when considering tinea capitis, tinea barbae and tinea unguium. Cure rates are higher and treatment courses are shorter with topical allylamines than with azoles. Terbinafine, itraconazole and fluconazole formulations are the most commonly used antifungals in systemic therapy.