(5) Dermatophytosis. Dermatophytosis is any superficial fungal infection of
the skin; for example, athlete's foot. Superficial skin infections are caused by
dermatophytes, fungi that invade only dead skin tissue or skin appendages such as the
stratum corneum of the epidermis, nails, or hair. Dermatophytes cause a variety of skin
lesions from mild and noninflammatory to acute causing a strong reaction by the body's
immune system. The term tinea means superficial fungal infection and in combination
with a second term indicates the location of the fungal disease (e.g., corporis, meaning
body). Here are several superficial fungal infections with their respective treatments.
(a) Tinea corporis (body ringworm). This fungus involves the body with
the exception of the scalp, hands, feet, groin, nails, and hair. This fungus can cause a
variety of skin lesions: noninflammatory, scaly plaques; inflammatory pustules; or deep,
tumorous lesions. Generally, there are only one to three lesions. Small lesions can be
treated with a two percent miconazole cream or a 1 percent alotrimazole cream or
lotion. Either medication should be rubbed on the affected area twice a day, continuing
7 to 10 days after the lesions disappear. Medication usually cures this fungus except in
persons who suffer from a disease that affects their entire system.
(b) Tinea pedis (athlete's foot). Ringworm of the feet, more commonly
known as athlete's foot, is a common fungal infection that usually begins between the
toes and eventually may appear on the arch of the foot. The most effective treatment is
griseofulvin. Medication should be started as soon as the disease is diagnosed.
Improvement may not be seen immediately. Griseofulvin may not cure the condition,
but it does prevent the disease from becoming more severe. Tinea pedis frequently
recurs, causing some patients to require treatment for many months. Complete cure of
athlete's foot is difficult, but this skin problem can be controlled with long-term therapy.
(c) Tinea capitis (scalp ringworm). This fungus mainly attacks children,
is highly contagious, and may become epidemic. There are three forms of tinea capitis:
inflammatory, noninflammatory, and favus (a chronic fungus infection of the scalp).
Oval patches of hair loss occur in noninflammatory tinea capitis. A boggy, pustular
nodule is present in inflammatory tinea capitis, and a crusty, scaly area around the hair
near its exit from the scalp is characteristic of favus. In most cases, this fungal infection
can be cured by giving microcrystalline griseofulvin, one twenty-fifth to one tenth mg by
mouth daily or twice daily for two weeks. This medication must be given with meals or
milk. A lotion or cream of two percent miconazole or one percent clotrimazole may be
rubbed in twice daily. This fungus is very persistent but usually clears up spontaneously
at puberty. Even if not treated, most scalp ringworm infections will clear up
spontaneously in one or two years.
(d) Tinea cruris (groin ringworm). This fungus, commonly called jock
itch, may be caused by several organisms. The fungus is more common in men than in
women, and itching may be severe. Lesions usually appear on the thighs. Tight
clothing, moisture, and heat cause the fungal organisms to grow. Athletes and other
individuals who perspire a lot are particularly susceptible to groin ringworm. Treatment
is two percent miconazole cream or one percent clotrimazole cream applied to the
lesions. The disease usually clears up promptly with treatment.