Athlete’s Foot, or tinea pedis, is the most common dermatologic (skin)
problem to affect the human foot. It is a fungal infection that affects the epidermal
(outer most) layer of the skin…most commonly within the interdigital (between
the toes) spaces. However, it can also affect the plantar (bottom) surface of
the foot. The most common pathologic fungus that causes tinea pedis is referred
to as a dermatophyte. The most common dermatophytes that cause athlete’s
foot are Microsporum, Epidermophyton, and Trichophyton. These strains of fungus
are many times components of normal body flora.
Athlete’s foot is common in adolescents and adults. It rarely occurs
in infants or geriatric patients. Dermatophytes thrive in warm, moist environments,
and commonly occur in people who don’t dry properly between their toes,
wear socks which are not clean, or have perspiration problems with their feet….a
condition referred to hyperhidrosis. For more information regarding this condition,
visit Dr. Tompkins’ Common Foot Problems section titled Sweaty Feet.
pedis is just one of the many types of fungal infections to occur in various
parts of the body. ‘Jock-itch’, or tinea cruris is a fungal
infection affecting the groin area of men; ‘Ringworm’, or tinea versicolor
is a fungal infection of the upper body, or torso; and ‘fungal nails’,
or onychomycosis, is a fungal infection that occurs under the nail plate (please
add a link to my page on onychomycosis). There are many other fungal infections
that affect the human body. Click for more information.
most common symptoms associated with athlete’s foot are an itching
(and sometimes burning) sensation associated with an erythematous (red and inflamed)
rash. This rash develops, again most commonly, between the toes and on the bottom
of the foot. If left untreated, the rash may spread and sometimes leads to small
blisters (vesicles) that become filled with a ‘fungal fluid’. This
type of athlete’s foot is referred to as vesicular tinea pedis. If the
rash occurs on the bottom of the foot, it many times affects the entire plantar
aspect of the foot, leading to a rash distribution referred to as ‘mocassin-type’ tinea
Tinea pedis can
only be specifically diagnosed with an appropriate fungal culture taken from
a specimen of the inflamed tissue. The most common test used in the definitive
diagnosis of tinea pedis, is called a KOH fungal culture. This can be performed
in the office setting by a qualified medical specialist. Scrapings from the inflamed
tissue are removed from the affected site, and mixed with a KOH (potassium hydroxide)
solution, and then visualized under a microscope. Characteristic fungal hyphae
will appear if there is a fungal component to the specimen. There are other fungal
cultures which can be used in the diagnosis of tinea pedis, but the KOH fungal-hyphae
test is the most common.
tinea pedis is so prevalent in the general population (approximately 5% of the
general population), the majority of people with mild cases of athlete’s
foot diagnose themselves. Most people who experience itching, burning, and/or
a rash associated with their feet, use one of the multiple OTC antifungal medications
available at local pharmacies, such as Tinactinâ, Micatinâ, or Lotriminâ,
etc. Advertising associated with these medications has lead to an explosion of
their use over the past few years as competitors enter(ed) the market….remember
John Madden’s “Take Action, and use Tinactin®”commercials!?If
the rash is truly caused by a fungus, and it is a relatively mild case of tinea
pedis, the itching normally subsides and the rash disappears within a week of
BID (twice a day) application of an OTC antifungal medication. With the exception
of Lamisil® topically, the remainder of the OTC antifungal
medications must be used for up to four weeks for complete resolution of athlete’s
more moderate to severe cases of athlete’s foot often require
prescription anti-fungal medications that can only be prescribed by a doctor.
There are a number of prescription- strength antifungal medications available
for doctors to use in the treatment of athlete’s foot. Occasionally, an
oral medication is necessary to treat more resistant and severe cases of athlete’s
foot. One of the most common oral medications used is called Griseofulvinâ.Due
to the widespread usage of these OTC medications, there have become an increasing
number of resistant strains of fungus that cause athlete’s foot.
This has required more patient visits to doctor’s offices for successful
treatment. In many cases of what appears to be a mild, typical case of athlete’s
foot, it is necessary to seek treatment from a qualified medical specialist for
The biggest complication in the treatment of tinea pedis is reoccurrence.
Successful treatment is dependent upon appropriate diagnosis, and sustained,
foot, like many fungal infections, has a heredity component. Many people are
just more susceptible to fungal infections and may recur on multiple occasions.
If simple application of one of the OTC antifungal medications twice a day, for
one-to-four weeks (depending upon the directions for each medication-which is
listed on the container), does not clear the rash and itching/burning, treatment
by a medical specialist is recommended.
left untreated, simple athlete’s foot can develop into more serious
bacterial infections that may spread and lead to the need for oral and sometimes
intravenous antibiotics. which occasionally may require hospitalization.