Symptoms and Signs of Ringworm

What does the term ringworm mean?

The term ringworm refers to fungal infections that are on the surface of the skin. The name is derived from the early belief that the infection was due to a worm, which it is not. Ringworm is a fungal infection in the skin.

Nevertheless, the name ringworm remains. Some of these fungi produce round spots on the skin, but many do not. On the other hand, many round, red spots on the skin are not due to a fungal infection. A physical examination of the affected skin, evaluation of skin scrapings under the microscope, and culture tests can help doctors make the appropriate distinctions. A proper diagnosis is essential to successful treatment.

The medical term for ringworm is tinea. Doctors add another word to indicate where the fungus is located. Tinea capitis, for instance, refers to scalp ringworm, tinea corporis to fungus of the body, tinea pedis to fungus of the feet, and so on.

Ringworm occurs in people of all ages, but it is particularly common in children. Ringworm is contagious and can be passed from person to person by contact with infected skin areas or by sharing combs and brushes, other personal care items, or clothing.

It is also possible become infected with ringworm after coming in contact with locker room or pool surfaces. The infection can also affect dogs and cats, and pets may transmit the infection to humans. It is common to have several areas of ringworm at once in different body areas.

Causes of ringworm?

Although the world is full of yeasts, molds, and fungi, only a few cause skin problems. These agents are called the dermatophytes, which means "skin fungi." An infection with these fungi is sometimes known as dermatophytosis. Skin fungi can only live on the dead layer of keratin protein on top of the skin. They rarely invade deeper into the body and cannot live on mucous membranes, such as those in the mouth or vagina.

Scientific names for the most common of the dermatophyte fungi that cause ringworm include Trichophyton rubrum, Trichophyton tonsurans, Trichophyton interdigitale, and/or Trichophyton mentagrophytes, Microsporum canis, and Epidermophyton floccosum.

What are the sources of skin fungi?

Some fungi live only on human skin, hair, or nails. Others live on animals and only sometimes are found on human skin. Still others live in the soil. It is often difficult or impossible to identify the source of a particular person's skin fungus.

The fungi may spread from person to person (anthropophilic), from animal to person (zoophilic), or from the soil to a person (geophilic).

Heat and moisture help fungi grow and thrive, which makes them more commonly found in skin folds such as those in the groin or between the toes. This also accounts for their reputation as being caught from showers, locker rooms, and swimming pools.

This reputation is exaggerated, though, since many people with "jock itch" or "athlete's foot" have not contracted the infection from locker rooms or athletic facilities.

What are risk factors for ringworm?

As described above, it is possible to acquire ringworm from a variety of places and circumstances. The greatest risk factor is coming in contact with an affected individual. Warm, moist areas are favorable conditions for the growth of fungi, so areas such as communal showers and locker rooms are areas in which transmission is favorable.

However, any contact with an infected person or a contaminated surface can lead to ringworm infection.

What are ringworm symptoms and signs?

The following are the different types of ringworm, or tinea:

1. Tinea barbae: Ringworm of the bearded area of the face and neck, with swelling and marked crusting, is often accompanied by itching, sometimes causing the hair to break off. In the days when men went to the barber daily for a shave, tinea barbae was called barber's itch.
2. Tinea capitis: Ringworm of the scalp commonly affects children, mostly in late childhood or adolescence. This condition may spread in schools. Tinea capitis appears as scalp scaling that is associated with bald spots (in contrast to dandruff, for instance, which do not cause hair loss).

Ringworm 
3. Tinea corporis: When fungus affects the skin of the body, it often produces the round spots of classic ringworm. Sometimes, these spots have an "active" outer border as they slowly grow and advance. It is important to distinguish this rash from other even more common rashes, such as nummular eczema. This condition, and others, may appear similar to ringworm, but they are not due to a fungal infection and require different treatment.
4. Tinea cruris: Tinea of the groin tends to have a reddish-brown color and extends from the folds of the groin down onto one or both thighs. Other conditions that can mimic tinea cruris include yeast infections, psoriasis, and intertrigo, a chafing rash which results from the skin rubbing against the skin.
5. Tinea faciei (faciale): ringworm on the face except in the area of the beard. On the face, ringworm is rarely ring shaped. Characteristically, it causes red, scaly patches with indistinct edges.
6. Tinea manus: ringworm involving the hands, particularly the palms and the spaces between the fingers. It typically causes thickening (hyperkeratosis) of these areas, often on only one hand. Tinea manus is a common companion of tinea pedis (ringworm of the feet). It is also called tinea manuum.

Athlete's Foot
7. Tinea pedis: Athlete's foot may cause scaling and inflammation in the toe webs, especially the one between the fourth and fifth toes. Another common form of tinea pedis produces a thickening or scaling of the skin on the heels and soles. This is sometimes referred to as the "moccasin distribution." In still other cases, tinea causes blisters between the toes or on the sole. Aside from athlete's foot, tinea pedis is known as tinea of the foot or, more loosely, fungal infection of the feet. Tinea pedis is an extremely common skin disorder. It is the most common and perhaps the most persistent of the fungal (tinea) infections. It is rare before adolescence. It may occur in association with other fungal skin infections such as tinea cruris (jock itch).
8. Tinea unguium: Finally, fungal infection can make the fingernails and, more often, the toenails yellow, thick, and crumbly. This is referred to as fungal nails or onychomycosis.

How is ringworm diagnosed?

Often, the diagnosis of ringworm is obvious from its location and appearance. Otherwise, skin scrapings for microscopic examination and a culture of the affected skin can establish the diagnosis of ringworm.

If the diagnosis is unclear, a potassium hydroxide (KOH) preparation of a skin scraping can be reviewed under the microscope to confirm the diagnosis of a fungal dermatophyte infection.

If a dermatophyte infection is present and the skin problem is misdiagnosed, inappropriate treatment might be prescribed that could actually worsen the infection.

What is the treatment for ringworm?

Home remedies cannot cure ringworm. To cure ringworm, it is necessary to take antifungal medications. Ringworm can be treated topically (with external applications) or systemically (for example, with oral medications):

Topical treatment: When fungus affects the skin of the body or the groin, many antifungal creams can clear the condition in around two weeks. Examples of such preparations include those that contain clotrimazole (Desenex cream, Lotrimin cream, lotion, and solution), miconazole (Nixoderm cream), ketoconazole (Nizoral cream), econazole (Spectazole), naftifine (Naftin), and terbinafine (Lamisil cream and solution).

These treatments are effective for many cases of foot fungus as well. Many of these antifungal creams are available as over-the-counter preparations. It is usually necessary to use topical medications for at least two weeks.

Systemic treatment: Some fungal infections do not respond well to external applications. Examples include scalp fungus and fungus of the nails. To penetrate these areas and in cases of particularly severe or extensive disease, oral medications can be used.

For a long time, the only effective antifungal tablet was griseofulvin (Fulvicin, Grifulvin, and Gris-PEG). Now, other agents are available that are both safer and more effective. These include terbinafine, itraconazole (Sporanox), and fluconazole (Diflucan). Oral medications are usually given for a three-month course.

How can ringworm be prevented?

Conventional wisdom holds that minimizing sweat and moisture can help prevent fungal infections. Common recommendations along these lines are for men to wear boxer shorts, for women to avoid panty hose, and so forth. Whether these measures, some of which are quite difficult to implement, are really worth all of the effort is open to question.

You can also take steps to prevent transmission of ringworm infections. Do not share clothing, towels, hairbrushes, combs, hair accessories, or other personal care items. Wearing sandals or shoes in gyms, locker rooms, and at pools can help reduce your chances of contracting athlete's foot. You should avoid touching pets that have signs of ringworm (typically bald spots).

What is the prognosis for ringworm?

Ringworm can be cured with appropriate treatment. Ringworm of the skin typically resolves after two to three weeks' treatment, while cases of ringworm of the scalp or nails may require treatment for a few months. Complications are rare and can include a secondary bacterial infection of the skin or a widespread fungal infection (extremely rare and more likely to occur in individuals with suppressed immune systems).