Dermatology A to Z
Fungal infections of the skin, hair, and nails are collectively known as tinea infections. These infections are also known as athlete’s foot, ringworm, “jock itch”, dermatophytosis and dermatomycosis. The fungi which cause these infections can be found in the soil, on animals and some can only live on humans. Of the 10,000 or so species of fungi, only 39 are known to cause these infections in normal individuals (only 11 are common and only 6 occur frequently in the US).
These fungi can live in the skin, hair and nails. They do not invade deeper except in individuals who are severely ill or immune suppressed (cancer, leukemia, AIDs, etc.). These fungi may be present without producing any symptoms at all in some individuals.
Fungal infections are named by the area of the body on which they occur: tinea capitis (scalp and hair), tinea manus (hands), tinea cruris (groin), tinea corporis (body) and tinea pedis (foot). Many people have fungal foot infections and often they regard the scaling and dryness of their feet as normal and do not seek treatment at all. Fungal infections may cause mild redness and scaling, or severe blisters. Fungi frequently cause circle like lesions with a red raised edge and normal central area (ringworm). Confirmation of your fungal infection may require scraping and microscopic examination or cultures and occasionally a biopsy.
Fungi can live in almost any type of environment. All they require is moisture and organic matter for energy. They thrive in warm, dark, moist places (such as a foot in a sock stuffed in a shoe). People who have had fungal foot or groin infections are prone to get them again. You should try to keep the area dry. Not going barefoot, drying completely after bathing (even using a blow dryer), using absorbent socks or underwear, and applying a bland dusting powder or antifungal powder will help prevent reinfection. Periodic application (once weekly) of an antifungal preparation containing tolnaftate (Tinactin), Lamisil, miconazole, haloprogin or clotrimazole will help.
Fingernail and toenail infections are very difficult to treat. Success requires long-term administration of an oral medication. The infection frequently recurs after clearing, especially toenail infections. Additionally, the medications may not be completely covered by many insurance plans. Nails that are painful due to thickening and curvature or distortion may be removed by surgery, chemicals or mechanical means.
Scalp and hair infections usually require oral medication as well as topical measures. They respond very well to treatment and can usually be easily cleared with good results.
Body, hand and groin infections, if involving only small areas and not causing severe inflammation, can be treated with topical preparations alone. Extensive or more severe infections will require oral medication.
Tinea infections on the feet may have been present for years. They will be improved by preventive measures and topical therapy, but sometimes require oral therapy for cure.