Athlete's foot, known medically as tinea pedis, is a common skin infection of the feet caused by fungus. Signs and symptoms often include itching, scaling, cracking and redness. In rare cases the skin may blister. Athlete's foot fungus may infect any part of the foot, but most often grows between the toes. The next most common area is the bottom of the foot. The same fungus may also affect the nails or the hands. It is a member of the group of diseases known as tinea.
The fungi (molds) that cause athlete's foot require warmth and moisture to survive and grow. There is an increased risk of infection with exposure to warm, moist environments (e.g., occlusive footwear—shoes or boots that enclose the feet) and in shared humid environments such as communal showers, shared pools, and treatment tubs. Chlorine bleach is a disinfectant and common household cleaner that kills mold. Cleaning surfaces with a chlorine bleach solution prevents the disease from spreading from subsequent contact. Cleaning bathtubs, showers, bathroom floors, sinks, and counters with bleach helps prevent the spread of the disease, including reinfection.
Athlete's foot was first medically described in 1908. Globally, athlete's foot affects about 15% of the population. Males are more often affected than females. It occurs most frequently in older children or younger adults. Historically it is believed to have been a rare condition, that became more frequent in the 1900s due to the greater use of shoes, health clubs, war, and travel.
^ Jump up to: a b American Academy of Dermatology (February 2013), "Five Things Physicians and Patients Should Question", Choosing Wisely: an initiative of the ABIM Foundation, American Academy of Dermatology, retrieved 5 December 2013. Which cites:*Roberts DT, Taylor WD, Boyle J (2003). "Guidelines for treatment of onychomycosis" (PDF). The British Journal of Dermatology. 148 (3): 402–410. doi:10.1046/j.1365-2133.2003.05242.x. PMID 12653730.
Starts at the base of the nail and raises the nail up: This is called "proximal subungual onychomycosis." This is the least common type of fungal nail. It is similar to the distal type, but it starts at the cuticle (base of the nail) and slowly spreads toward the nail tip. This type almost always occurs in people with a damaged immune system. It is rare to see debris under the tip of the nail with this condition, unlike distal subungual onychomycosis. The most common cause is T. rubrum and non-dermatophyte molds.
The most reliable way to diagnose athlete’s foot is to correctly identify its cause. Fungal athlete's foot is relatively straightforward to diagnose and treat. Visualization of the fungus in skin scrapings removed from the affected areas of the feet is a painless and cost-effective method for diagnosis. Rarely, it is necessary to identify fungi in portions of skin removed during a biopsy. If no fungus is found, other causes of athlete's foot must be investigated.
If you have diabetes, you may have reduced blood circulation and nerve supply in your feet. You're also at greater risk of a bacterial skin infection (cellulitis). So any relatively minor injury to your feet — including a nail fungal infection — can lead to a more serious complication. See your doctor if you have diabetes and think you're developing nail fungus.