Fungal foot infection, nail fungus
Fungal foot infection (tinea pedis) is a skin, hair and nail infection caused by a dermatophyte fungus. Dermatophytes are aerobic fungi that can decompose and obtain nutrients from keratinized material and that parasitize in human keratin tissues (hair and nails). The infection is very common: almost 70% of people are infected at one time in their life.
To become infected, a sufficient amount of infectious material must be deposited on skin (e.g. by wearing other people’s shoes, walking barefoot in a public sauna, or shower) and the environment must promote fungal growth. Risk factors are microtraumas, profuse perspiration of feet, skin maceration, closed footwear, warm and humid climate, blood circulation disorders of the feet, diabetes, and immunosuppression.
The symptoms of a fungal foot infection are itching, scaling, unpleasant smell, profuse perspiration of feet, and, when fissures develop, stinging sensation and painfulness. There are three forms of fungal foot infection:
- Interdigital tinea pedis – occurs most often between the fourth and fifth toes with moist, macerated (wrinkled) and pale skin. Fissures develop between and below toes; there is some scaling.
- Hyperkeratotic (moccasin type) tinea pedis – slight redness on the soles and whitish flaky scaling in skin folds. Inflammation spreads up from the heel and extends onto the sides of the foot; the dorsal surface of the foot is typically not affected.
- Vesicular or dyshidrotic tinea pedis – following a long symptom-free period, itchy vesicles that contain cloudy or purulent fluid develop suddenly on the instep or anterior plantar surface of the foot. After rupture of vesicles, erosions, scaling and redness follow. The situation may be complicated by a secondary bacterial infection accompanied by purulent vesicles. If the patient scratches these vesicles too strongly, they may develop bloody contents.
When a nail is infected, the coloration of the nail changes, spots or stripes develop, the nail is deformed and starts to crumble.
To diagnose a fungal infection, we confirm it by using a microscope and by culture, for which material is gathered from skin scales, contents of vesicles, nails, etc., where it is possible to determine the pathogen.
Treatment of fungal infection is either local or systemic. Local treatment (gel, ointment, cream) can be used for the treatment of modestly or moderately developed infection. Systemic treatment (tablets or capsules) is necessary with widespread disease or in severe cases. Systemic treatment can also be necessary for patients with diabetes, limb circulation problems or immunosuppressed patients (due to medication or illness).