Ringworm Dermatophytosis
What is it?
Ringworm is a very common skin infection caused by several different species of fungi collectively referred to as tinea. The infection causes scaly, round, itchy patches that develop on various parts of the body, including the scalp, groin, nails, feet, and the skin under the beard. Prompt treatment usually clears up most cases within a few weeks.
What Causes It?
- Infection by fungi. Exposure to animals (especially cats and dogs) with a fungal infection is one mode of transmission.
Prevention
- Do not share towels or shoes.
- Thoroughly dry the feet after taking a bath or shower, and after swimming.
- Avoid lengthy stays in an overheated, humid environment, like the areas around indoor swimming pools.Warmth, moisture, and darkness encourage the growth of fungi.
- Avoid contact with infected pets as much as possible. Seek prompt veterinary treatment for any skin conditions your pet exhibits.
Diagnosis
- Ringworm is suspected by observation of the characteristic red-bordered rash.
- Direct microscopic examination of the scales obtained after scraping the lesion usually proves the presence of the microorganism.On occasions, a culture of these scrapings is needed.
How to Treat It
- Ringworm can often be cured with over-thecounter antifungal creams or solutions, especially those containing terbinafine, clotrimazole, miconazole, or ketoconazole. Generally, these are applied once or twice daily; the infection should begin to fade within a week. Continuing treatment for the recommended amount of time will help ensure eradication of the fungus.
- If over-the-counter treatments fail, a more powerful oral agent may be prescribed. Similarly, infection of the nails or scalp usually requires systemic (oral) treatment.
- Keep affected areas as clean and dry as possible; talcum or medicated powder may be used.
- If a fungal infection begins to blister or ooze, apply damp compresses to help clear out the affected areas. Do not break blisters; this can spread the infection.
- If you have ringworm of the groin area (jock itch), wear cotton underwear and change it more than once a day. If your feet are affected (athlete's foot), change socks frequently to keep your feet dry.
- Clotrimazole powder should be applied to the shoes to prevent reinfection of athlete's foot.
When to Call a Doctor
- Call your doctor to confirm the diagnosis, and if symptoms do not improve or if infection continues to spread after several weeks of over-the-counter treatment.
- Call a doctor if you develop new, unexplained symptoms, which may be side effects from the medications used to treat ringworm.
- Call your doctor if you suspect scalp ringworm.
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Copyright © 2008 Medletter Associates, LLC
Content excerpted from Johns Hopkins Symptoms and Remedies: The Complete Home Medical Reference.