Can you get athlete's foot anywhere besides your feet?

There's a fungus among us, and it's making us miserable. The culprit is part of the genus Trichophyton. It belongs to a class of fungi called dermatophytes and lives in the epidermis, or the outer layer of skin, where it dines exclusively on the protein keratin. Keratin is tough: It's a major component in skin (as well as horns and claws in other animals), where it helps keep out germs and other foreign invaders.

Trichophyton is among a relative handful of microbes equipped with the enzyme needed to break down keratin's fibrous composition. Obligingly, you turn out new epidermal cells every four weeks, providing the fungus with an endless, all-you-can-eat feast.

Like other fungi, Trichophyton thrives in warm, moist areas. On the human body, that's primarily the scalp, groin and feet. Infection by Trichophyton is called tinea, from the Latin word for larva. Infected patches sometimes resemble the holes that moth larvae gnaw in woolen clothing. From this resemblance comes its common English name, ringworm.

Ringworm takes other names, some of them even more descriptive, depending on the body part infected. A general outbreak is calledtinea corporis, ringworm of the body. If it occurs on the scalp, it's tinea capitis, ringworm of the head. In the groin or buttocks, the condition is called tinea cruris, better known as jock itch. An infection of the foot is tinea pedis -- which is casually called athlete's foot.

While no worms are involved in ringworm, it may make you feel like you're being munched on by moths. Your skin turns red and scaly. It cracks, peels and itches. Infected nails can crumble and separate from their beds. Bald patches can open on the scalp.

How does Trichophyton find its way to your skin? How can you prevent it from settling in -- or, failing that, get rid of it? What happens if you don't? Where can you get relief?

Where It Starts, Where It Leads

Just as ringworm has nothing to do with worms, you don't have to be a jock or an athlete to get it. In fact, some of Trichophyton's favorite hosts have just learned to play catch. They're children.

Why? Trichophyton spreads easily through both direct and indirect contact. Kids in school jostle each other in the lunch line. Friends share pencils and baseball caps. Siblings share living space. One family can infect an entire neighborhood. The fungus lives in animal skin, as well. The family dog or cat and the classroom rabbit can be carriers. Not surprisingly, children are more likely than adults to contract ringworm of the body and scalp.

Fungi crave humid conditions, and dermatophytes love bare skin. You'll find plenty of both in the gyms, swimming pools and locker rooms where athletes congregate. Then again, feet that never set foot in a gym but spend time in dirty, sweaty socks are targets. Men and teen boys are most prone to contracting jock itch and athlete's foot.

Some people are especially susceptible to infection. People with compromised immune systems, such as those who have AIDS or cancer, are at higher risk. If you're prone to other fungal infections, you're a better-than-average candidate for ringworm.

Trichophyton is pernicious. Even after you wipe out the main colony with sprays and powders, small growths can linger out of reach in folds and layers of skin.

If ringworm isn't treated, things can go from bad to worse. With keratin degraded, the skin weakens and cracks. Bacteria invade, along with the associated ills of infection: fever, pus, and added heat, pain and swelling. People with poor circulation in the limbs are more apt to suffer these secondary infections. Those with diabetes are especially at risk of complications related to athlete's foot. Some people develop fluid-filled, weeping blisters, an allergic reaction to the fungus and the protein by-products of keratin breakdown.

You most likely will be driven to seek relief before it reaches that stage -- first to the drugstore, and possibly to the doctor's office.

Lines of Treatment

You can avoid the trials of Trichophyton by following two basic rules: Keep clean and dry, and practice good hygiene. For example:

Bathe or shower daily. Follow up with talcum powder, which keeps skin dry.
Wear clean clothes, especially socks, stockings and underwear.
Wear loosely woven, "breathable" clothes when possible. Check clothing labels for fabrics made with "wicking" microfibers (usually polyester and nylon blends), which draw and disperse moisture from the body to speed evaporation.
Avoid sharing shoes, clothing or personal care items, such as combs and bath towels.
Wear waterproof sandals or other protective foot gear in public places where bare feet meet -- the health club, the spa, the college dorm showers.
If you use a pedicurist, bring your own tools.
Keep rooms well-ventilated. Disinfect bathrooms as part of your cleaning routine.

If an infection does set in, over-the-counter sprays, powders or shampoos are the usual first course of treatment. These topical medications combine an antifungal that attacks Trichophyton's cell walls with a cortisone-based drug to ease the inflammation. It often takes several weeks to root out the fungus from all the nooks and crannies.

Studies show that some plant extracts also have antifungal qualities. Ointments containing tea tree oil or ajoene, a sulfuric compound found in garlic, may be helpful.

Complications from ringworm require a doctor's care. The doctor may view skin scrapings under a microscope to make sure Trichophyton is to blame. He or she may prescribe stronger topical antifungals or oral medications, especially for bacterial scalp infections. Antibiotics may also be prescribed. Some oral medications can bring unpleasant side effects, ranging from upset stomach to impaired liver function. Other medication you may be taking will also influence the choice of treatment.

Can you get athlete's foot anywhere besides your feet?

Where It Starts, Where It Leads

Lines of Treatment

Lots More Information

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