What is athlete's foot?
Athlete's foot is the term used for a common disorder affecting the skin between the toes. The cleft between the fourth and fifth toes is the most frequently affected, with moist soft skin that peels off easily. Often the skin splits uncomfortably (a fissure). It may smell unpleasant. It is generally mild; very inflamed athlete's foot is generally due to secondary bacterial infection.
What causes athlete's foot?
Athlete's foot can be due to one factor or a combination of factors.
- Bacterial infection (erythrasma, pseudomonas, staphylococci and streptococci).
- Mould infection.
- Soft corn (build-up of thick skin because the toes are pressing against each other).
- Injury e.g. over-vigorous removal of peeling skin.
- Skin conditions such as psoriasis, eczema or keratolysis exfoliativa.
- Fungal infection (tinea pedis).
Athlete's foot is more common in those who participate in sports because:
- They may wear occlusive footwear.
- They sweat heavily.
- They may fail to dry their feet carefully after showering.
- They are exposed to fungal spores on the surfaces of communal areas.
How is athlete's foot diagnosed?
The diagnosis is usually clinical, as athlete's foot has a characteristic appearance. If resistant to treatment, investigations are undertaken to identify a specific infection (if present):
- Wood's light (ultraviolet) examination looking for coral-red fluorescence, characteristic of erythrasma.
- Swabs for bacterial microscopy and culture.
- Scrapings for fungal microscopy and culture.
If there is no infection, or treatment of infection does not control the symptoms, an underlying skin condition could be responsible. Look for signs of psoriasis (scaly patches in scalp, on elbows and knees or rashes in body folds) or dermatitis (itchy areas of dry skin).
Was is the treatment of athlete's foot?
Treatment for athlete's foot should begin with general measures.
- Dry carefully between the toes.
- Keep toes apart using a cotton or foam wedge.
- Wear shoes that are loose around the toes or go bare foot.
- Apply a topical antifungal agent. These may also control many of the bacteria responsible for athlete's foot.
Whitfield's ointment is particularly useful as it removes the surface layer of moist peeling skin (i.e. it is keratolytic) and eliminates bacteria and fungi.
Make sure that other sites of fungal infection are also treated effectively. Prevent relapse by using antifungal foot powder.