A variety of fungal infections of the skin, scalp and nails fall under the general category of ringworm. (The name ringworm, which dates from the 15th century, is a misnomer; no worm is involved and the rash is not always circular.)
The fungi that cause ringworm can be found almost everywhere. As a result, ringworm infections are particularly common among children in day care and in the early school years.
Once ringworm sets in, it nourishes itself by absorbing the dead, protein-rich material called keratin that comprises the outer layer of skin. Although it is not dangerous, ringworm can make a child very uncomfortable by causing itchiness and sometimes painful fissures in the skin. Ringworm of the scalp is also often quite unsightly since it causes the loss of hair in patches.
WHAT CAUSES RINGWORM?
The infectious organisms that cause ringworm fungi are known as dermatophytes. The types that most commonly affect children are:
• Tinea corporis (the classic ringworm of body skin). This infection is marked by circular, scaly lesions with clear skin in the center. The lesions are most common on the arms or the trunk of the body, and they grow as the fungus depletes the nutrient supply on the skin surface within the circle. Tinea corporis occurs most frequently in young boys.
• Tinea capitis (scalp ringworm). This highly contagious infection spreads rapidly among school children, causing hair loss and scaling on the scalp. It is most common in young boys and rare after puberty.
• Tinea unguim (ringworm of the nails). This infection attacks toe nails and (less frequently) fingernails, causing unsightly nail thickening, discoloration and crumbling.
• Tinea pedis (athlete's foot) appears either as dry scaly patches or as wet, blistery lesions between the toes and on the sole of the foot. It is not common in young children.
• Tinea cruris (jock itch) affects the goin area with lesions of the scrotum and the upper, inner thighs. It is most common among pubescent males and adult men.
WHEN SHOULD I SUSPECT RINGWORM?
Ringworm does not always cause itching. Instead, look for a circular rash, hair loss or scaly patches on the skin or scalp.
IS MEDICAL ATTENTION NECESSARY?
Yes. You should consult your pediatrician when any new rash appears.
If the rash is a recurrence of an earlier fungal infection, treat it as initially instructed by the physician. If it does not respond to treatment in a week, contact the pediatrician and discontinue use of the topical agent.
HOW CAN THE PEDIATRICIAN RECOGNIZE RINGWORM?
The doctor usually can diagnose ringworm by simple observation because of the characteristic appearance of the lesions. If there is any doubt, microscopic examination of scales or hairs may reveal the presence of the fungi or a culture can be obtained in the office.
WHAT TREATMENTS ARE AVAILABLE?
Most fungal infections are easily treated with topical antifungal agents—creams for dry eruptions and powders for wet ones. Physicians often recommend one of three successful over-the-counter drugs called tolnaftate, clotrimazole and miconazole. Most of these drugs work by interfering with the structure of the fungal membranes. Improvement begins quickly, but complete cure (even of simple ringworm) may take a month of therapy. If the lesion does not improve after a week, discontinue using the product and notify the physcian.
Severe fungal infections may require a prescription topical medication or oral drugs. Oral medication is always necessary for ringworm of the scalp because the fungus can penetrate the hair follicles beneath the skin. Ringworm of the nails also requires oral medication and may take months to resolve completely.
PREVENTING RINGWORM
The following guidelines can help protect children from fungal infections and speed healing if ringworm is present:
• Apply an antifungal powder to cut down on perspiration that can build up in the folds of skin.
• After the child has been sweating, have him shower; dry skin carefully and reapply powder.
• Buy cotton socks and underwear, which absorb perspiration.
• Teach your child not to use other children's towels, washcloths and hairbrushes.
GETTING HELP
Call your doctor if your child:
• Develops any new rash
• Has been diagnosed with ringworm and the prescribed treatment has no effect within a week
