The term tinea corporis, often called ringworm, is frequently caused by dermatophyte fungi. It is thus a fungal condition which affects the skin, and which appears as red patches in the form of rings which gradually extend while the central portion clears. Very severe itching can sometimes be added. The fungus can be transmitted by humans, a pet, or an infected surface. The diagnosis is clinical, sometimes supplemented by an examination using an ultraviolet light, in case of doubt. Ringworm can be treated with antifungal creams or corticosteroids in case of severe itching. In case of lesions, an oral antimycotic may be necessary.