An infection of the body surface with mold-like fungi called dermatophytes.
Causes, incidence, and risk factors
Ringworm is a common skin disorder, especially among children, but may occur in people of all ages. It is caused by mold-like fungi (dermatophytes). See tinea corporis , also see tinea capitis (ringworm involving the scalp), tinea cruris (ringworm of the groin, also called jock itch ), and tinea pedis (ringworm on the feet, also called athlete's foot ).
Signs and tests
The diagnosis is primarily based on the appearance of the skin. Certain species of fungus will appear florescent if the skin is examined with a special blue light, called a Wood's lamp, in a dark room. A more definitive diagnosis can be made by scraping the affected area of skin and examining the cells under a microscope. The fungi have a characteristic "spaghetti and meatballs" appearance. The skin scrapings can also be sent to the microbiology laboratory, and the fungus will grow in the culture medium.
Treatment
Ringworm usually responds to self-care. Keep the skin clean and dry. Over-the-counter antifungal or drying powders, lotions, or creams are applied to the affected skin. Those that contain miconazole, clotrimazole, or similar ingredients are often effective in controlling ringworm. Severe or persistent infection may require further treatment by the health care provider. Oral antifungal medications may be given, and are necessary if the hair is involved. Stronger, prescription topical antifungal medications, such as ketoconazole or sulconazole may be needed. In some cases, topical corticosteroids may be added to the topical antifungals. Antibiotics may be needed to treat secondary bacterial infections.
Expectations (prognosis)
Ringworm usually responds to topical treatment within 4 weeks. Severe or resistant cases usually respond promptly to oral antifungal therapy.
Calling your health care provider
Call for an appointment with your health care provider if ringworm does not improve with self-care, or if symptoms persist longer than 4 weeks.
Prevention
Good general hygiene helps prevent ringworm. Keep the skin clean and dry. The fungus is slightly contagious, so clothing, hairbrushes, or other items should be thoroughly cleaned and dried after use.