Tinea pedis (athlete’s foot)

Tinea pedis, colloquially known as athlete’s foot, is the most common fungal infection in humans. It affects around one in three adults in the course of their lives. The disease is caused by filamentous fungi, so-called dermatophytes, with Trichophyton rubrum being the most common pathogen.

Causes

Transmission occurs through direct contact with infected skin flakes in public places such as swimming pools, saunas, changing rooms or hotel floors. Sharing towels or shoes can also lead to infection. Various factors increase the risk: increased sweating on the feet, tight-fitting, non-breathable footwear, lack of foot hygiene, weakened immune system, circulatory disorders, especially in diabetes mellitus and foot malpositions. Men are more frequently affected than women.

A distinction is made between different forms: The interdigital form is the most common at 80 percent and affects the spaces between the toes, particularly between the fourth and fifth toes.

Symptoms

The skin appears white, softened, scaly and may show cracks with severe itching and often an unpleasant odor. The squamous-hyperkeratotic form shows dry, thickened skin with pronounced scaling on the sole and edges of the foot. The vesicular-dyshidrotic form is less common and is characterized by itchy blisters on the arch of the foot. If left untreated, athlete’s foot can spread to the toenails and cause nail fungus.

Bacterial superinfections are also possible.

Diagnosis

The diagnosis can often be made clinically. To confirm the diagnosis, skin flakes are removed and examined microscopically or cultivated in a fungal culture.

Treatment

In mild to moderate cases, topical treatment with antifungal creams, sprays or powders is sufficient. The active ingredients are clotrimazole, miconazole or terbinafine. Treatment should be continued consistently for two to four weeks. Oral antimycotics are necessary for extensive infestations. As a preventative measure, feet should be washed daily and dried thoroughly, bathing shoes should be worn in public areas, breathable shoes should be preferred and socks should be changed daily.