Topical treatment of common superficial tinea infections

Tinea infections are superficial fungal infections caused by three species of fungi collectively known as dermatophytes. Commonly these infections are named for the body part affected, including tinea corporis (general skin), tinea cruris (groin), and tinea pedis (feet). Accurate diagnosis is necessary for effective treatment. Diagnosis is usually based on history and clinical appearance plus direct microscopy of a potassium hydroxide preparation. Culture or histologic examination is rarely required for diagnosis. Treatment requires attention to exacerbating factors such as skin moisture and choosing an appropriate antifungal agent. Topical therapy is generally successful unless the infection covers an extensive area or is resistant to initial therapy. In these cases, systemic therapy may be required. Tinea corporis and cruris infections are usually treated for two weeks, while tinea pedis is treated for four weeks with an azole or for one to two weeks with allylamine medication. Treatment should continue for at least one week after clinical clearing of infection. Newer medications require fewer applications and a shorter duration of use. The presence of inflammation may necessitate the use of an agent with inherent anti-inflammatory properties or the use of a combination antifungal/steroid agent. The latter agents should be used with caution because of their potential for causing atrophy and other steroid-associated complications.