Tinea is the name given to a fungal skin infection. Most people
will develop some resistance to skin fungus after being infected.
Others appear to have a susceptibility to fungal infections.
Sometime the susceptibility will run in the family.
Tinea pedis (athlete's foot)
This is the commonest type of fungal infection. It is the most
common and most stubborn cause of tinea pedis and only affects
humans. It is spread by direct contact, most often through bare
feet in bathrooms and health clubs. Leather or plastic footwear
that doesn't "breathe" encourages tinea pedis. It is
rare in children.
In most cases, the skin be comes white, soft and peels away
between the toes (especially between the fourth and little toes).
It may infect the sole of the foot. resulting in peeling, scaling,
itching and sometimes blistering. Only one, or both feet may be
involved.
Onychomycosis (Tinea Ungium of the nail)
Toe nail infection is usually associated with tinea pedis. It
is very difficult to eradicate. Often the great toenail is the
first to show signs, especially if it has been injured. The nail
yellows, and after years thickens and breaks easily. Finger nail
infections are similar, but less common.
Tinea cruris (Jock itch)
Some subjects with tinea pedis also develop a rash in the groin
(tinea cruris), especially if they tend to sweat a lot. It is
common and affects men more often than women. It has an itchy
spreading red border.
Tinea corporis (ringworm)
Tinea corporis may be spread from person to person, from
contact with an infected cat, most often a kitten, or from
exposure to fungus in the soil.. Itchy red scaly patches come up
anywhere. the cat has rubbed. They often develop into a ring. This
kind of tinea usually clears up with appropriate creams. If due to
a cat, even if the cat has no signs of a skin problem it will need
treatment too.
Trichophyton verrucosum is a cattle ringworm and infects
farmers. It arises on exposed skin as an inflamed red patch
studded with pustules.
Tinea capitis (scalp ringworm)
Tinea capitis usually occurs mostly in children and results in
scaling and patchy hair loss. It is epidemic in many
african-american communities. The scalp can look quite moth-eaten
but with the right treatment the hair will grow back normally and
will not result in permanent hair loss.
An exception may be a kerion; this is a very inflammatory tinea
of the scalp and looks like a boil or abscess. It is hard to
immediately confirm that the symptoms are due to tinea infection
and to establish the identity of the infecting organism. This is
treated with prednisone to prevent permanent hair loss.
Treatment
Tinea infections can be treated by a variety of different
medications. For tinea Pedis, Cruis and Corporis creams such as
Lamisil-AT and Micatin AF. can be bought over the counter at a
pharmacy. Prescription creams are stronger, faster and require
less applications. Sometimes oral medications are necessary. These
are very effective, and include Griseofulvin (Grispeg, Fulvicin),
Lamisil (Terbinafine), Sporonox (Itraconazole), and Diflucan (Fluconazole).
Tinea Capitis, Tinea unguium and chronic tinea pedis are difficult
to eradicate completely and require oral treatment.
Prevention
People with tinea pedis should discourage further growth of the
fungus by keeping their feet as dry as possible. Wear open-toed
sandals whenever possible, avoid boots, dry carefully after
washing, and use a antifungal foot powder (Zeasorb-AF) daily. See
"recurrent fungal infections"
TINEA VERSICOLOR
Tinea versicolor is cause by a different type of skin fungus.
In this infection, overgrowth of a yeast like germ present on
normal skin is the cause. If the skin is oily enough, warm enough
and moist enough, it starts to grow into small
"colonies" on the surface of the skin. In these colonies
the yeast grows like crazy and leaks out an acidic bleach. This
changes the skin color. The patches are lightly reddish brown on
very pale skin but they don't tan. Because of lack of any tanning,
they look like white spots on darker or tanned skin. This is most
often seen on the neck, upper chest, upper arms and back. There
may be a fine, dry scale on it.
Usually the infection produces few symptoms, but some people
get itching, especially when sweating. The warmer the weather, the
worse this condition gets. Tanning booths are warm places, so
avoid them. The reasons why some get this problem and others do
not are not known.
This infection can easily be recognized by a dermatologist, but
occasionally it can be mistaken for vitiligo, pityriasis or other
skin conditions. If there is any doubt, a "KOH prep", a
test done quickly in the office will confirm the diagnosis.
The infection is treated with either topical or oral
medications. In very mild cases, non-prescription antifungal
creams (Lotrimin-AF, Micatin) will work. Prescription antifungal
lotions and sprays (Oxistat lotion, Lamisil spray) may work
better. The most economical effective treatment is to apply
antifungal shampoo (Nizoral, Excel) to the body as if it were
soap, but leave it on for some minutes before washing.
For severe, extensive or recurrent cases, a few tablets of
Nizoral pills will clear things up. A newer pill, Sporonox, may
replace Nizoral for this problem. These will all eliminate the
fungus and relive any itch and scale. The uneven color of the skin
will remain several months, perhaps until you get a tan again in
the next summer.
Remember, since we all have some of this fungus, so no
treatment can prevent you from picking it up again forever. In
many people, the rash reappears for the next few years. To prevent
recurrence, preventative re-treatment with the same medication may
be advised. We don't often see this condition beyond mid-life, so
rest assured it won't keep coming back forever.