It is one of the most common skin infections to affect both children and adults with about 7 in 10 people experiencing athlete’s foot at some point in their life. Athlete’s foot can be difficult to treat in some cases. However, these skin fungi can be completely eradicated in time.
What is athlete’s foot?
Athlete’s foot is a fungal infection of the skin on the feet. It can affect one or both feet. This is also known as a ringworm infection because the fungus causes a characteristic red ring-like lesion. However, it is important to note that the a fungus is not a worm. Therefore the term ringworm can be misleading. Furthermore the term athlete’s foot is also incorrect because this skin conditions does not only affect athletes. The medical term for athlete’s foot is tinea pedis with tinea referring to a fungal skin infection and pedis referring to the feet.
Causes of Athlete’s Foot
Fungi are present everywhere and contact with fungi cannot be avoided. However, fungal infections like athlete’s foot are caused by a only a few fungal species. Furthermore the skin is a very effective barrier and fungal infections are more likely to arise under certain conditions. These skin infections are limited to the outermost layers of skin. In other words it is a superficial and does not pose any serious threat.
The fungi that causes athlete’s foot has enzymes that can digest human skin. These enzymes, known as keratinase, are able to digest the hard protein that makes up the outermost skin layers. This protein is known as keratin. Therefore the fungus is able to sustain itself by consuming keratin in human skin but does not extend into deeper tissue. This type of keratin-digesting fungi are known as dermatophytes.
The most common dermatophyte to cause athlete’s foot is Trichophyton rubrum. Two other fungi known as Trichophyton mentagrophytes and Epidermophyton floccosum are other fairly common fungal species to cause athlete’s foot. Since dermatophytes prefer areas of the skin that are warm and moist, the feet is one of the ideal environments for a fungal infection to occur. Some people may be genetically predisposed to fungal skin infections.
Other fungi known as yeasts can also infect the skin on the feet. However, yeast infections of the skin on the feet are not as common as dermatophyte infections. The main yeast to cause these skin infections is Candida albicans and sometimes the other Candida species of yeasts. Therefore these infections are referred to as cutaneous candidiasis. Sometimes a rare type of yeast can also infect the skin on the feet and cause black patches on the soles. This yeast infection is known as tinea nigra.
Read more on tinea nigra.
Signs and Symptoms
Athlete’s foot may affect one foot or both feet. This fungal infection of the skin may also occur at other sites on the body like on the hands and even the groin. The infection may have started on the foot but with touching and scratching the infected area, the fungus can be then spread to other parts of the body.
In athlete’s foot, the infection can occur anywhere on the foot. It is less common on the soles although another fungal infection known as tinea nigra targets the soles specifically. The area between the toes (web of the toes) is a commonly affected site. Sometimes the fungal infection may also affect the toenails.
The typical rash of athlete’s foot is often described as a round-shaped rash with a red border and dry to scaly skin in the center. Sometimes the skin at the center can look like normal skin but the fungus is still present at the area. The red ring border is the reason why athlete’s foot is also called foot ringworm.
However, the skin rash may not always appear as typical. The rash may be any shape and the red border may not always be as clearly demarcated or symmetrical as a ring. Sometimes the entire rash may be red and scaly with broken skin and open sores (ulcers).
Tiny blisters on the rash are another common symptom. Sometimes the skin appears normal with a bit of dryness and many blisters. There is no typical rash of scaling or peeling skin. When these blisters burst, it oozes a clear sticky fluid. This often occurs with scratching the area. However, when the rash becomes infected with bacteria then there may be small abscesses. The discharge from the boils or blisters may be a yellow color.
Itching is another common symptoms of athlete’s foot. The area may itch intensely and vigorous scratching often does more damage to the skin than the fungus itself. Sometimes scratching the area may also cause a clear fluid to discharge from the area. The skin may also slough off with scratching and tiny specks may be seen. These specks may vary from a white to brown color. Itching may intensify when the area becomes warm and moist.
Read more on itchy feet.
Pain and Burning
Pain at the site of the infection is not common unless the skin is broken. It may be seen with ulcers which are open sores. Vigorous scratching and a secondary bacterial infection of the affected skin may also lead to pain. Burning is another symptom that may sometimes be experienced when the skin is broke or there are open sores (ulcers). Pressure on the affected are may worsen the pain and burning.
Treatment of Athlete’s Foot
The focus of athlete’s foot treatment is to eradicate the fungus. Gradually the skin will heal and symptoms resolve. Eradicating the fungus may involve topical (surface) or oral (internal) medication. The latter is reserved only for severe cases that is not responding topical applications like ointments, creams and gels. It can take 1 to 2 months to eradicate the fungus.
The substances within the topical and/or oral antifungal agents include terbinafine, ketoconazole and miconazole. Some topical antifungal applications are available over-the-counter without a prescription. If these applications do not eradicate the fungus then stronger topical applications and even oral medication may be prescribed. Antibacterial ointments may also be used if there is a bacterial infection at the site.