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Athlete's foot (also known as ringworm of the foot, tinea pedum,〔Braun-Falco, Otto et al. 2000. ''Dermatology.'' Berlin: Springer, p. 323.〕 and moccasin foot〔) is a common and contagious skin disease that causes itching, scaling, flaking, and sometimes blistering of the affected areas. Its medical name is tinea pedis,〔 a member of the group of diseases or conditions known as tinea, most of which are dermatophytoses (fungal infections of the skin, hair, or nails).〔 Globally, athlete's foot affects about 15% of the population. Tinea pedis is caused by the mold known as ''Epidermophyton floccosum'' or molds of the ''Trichophyton'' genus of fungi, including ''T. rubrum'', ''T. mentagrophytes'', and ''T. tonsurans'' (more common in children).〔 These parasitic fungi are typically transmitted in moist communal areas where people go barefoot, such as around swimming pools or in locker rooms, and require a warm moist environment like the inside of a shoe to incubate. Fungal infection of the foot may be acquired in many ways, such as by walking in an infected locker room, by using an infested bathtub, by sharing a towel used by someone with the disease, by touching the feet with infected fingers (such as after scratching another infected area of the body), or by wearing fungi-contaminated socks or shoes. The fungi may spread to other areas of the body, such as by scratching. The fungi tend to infect areas of skin that are kept warm and moist, such as with insulation (clothes), body heat, and sweat. However, the spread of the infection is not limited to skin. Toe nails become infected with fungi in the same way as the rest of the foot, typically by being trapped with fungi in the warm, dark, moist inside of a shoe. Infection can often be prevented by keeping the feet dry by limiting the use of footwear that enclose the feet, or by remaining barefoot. To treat athlete's foot, it is necessary to prevent its spreading back to the feet by treating the entire infection, wherever it is on the body, until the fungi are dead and the skin has fully healed. There is a wide array of over the counter and prescription topical medications in the form of liquids, sprays, powders, ointments, and creams for killing fungi that have infected the feet or the body in general. For persistent conditions, oral medications are available by prescription. == Signs and symptoms == Athlete's foot is divided into four categories or presentations: chronic interdigital athlete's foot, plantar (chronic scaly) athlete's foot (aka "moccasin foot"), acute ulcerative tinea pedis,〔 and vesiculobullous athlete's foot.〔〔(【引用サイトリンク】 title=Athlete's Foot )〕 "Interdigital" means between the toes. "Plantar" here refers to the sole of the foot. The ulcerative condition includes macerated lesions with scaly borders.〔 Maceration is the softening and breaking down of skin due to extensive exposure to moisture. A vesiculobullous disease is a type of mucocutaneous disease characterized by vesicles and bullae (i.e. blisters). Both vesicles and bullae are fluid-filled lesions, and they are distinguished by size (vesicles being less than 5–10 mm and bulla being larger than 5–10 mm, depending upon what definition is used). Athlete's foot occurs most often between the toes (interdigital), with the space between the fourth and fifth digits most commonly afflicted. Cases of interdigital athlete's foot caused by ''Trichophyton rubrum'' may be symptomless, it may itch, or the skin between the toes may appear red or ulcerative (scaly, flaky, with soft and white if skin has been kept wet), with or without itching. An acute ulcerative variant of interdigital athlete's foot caused by ''T. mentagrophytes'' is characterized by pain, maceration of the skin, erosions and fissuring of the skin, crusting, and an odor due to bacterial infection of the skin.〔 Plantar athlete's foot (moccasin foot) is also caused by ''T. rubrum'' which typically causes asymptomatic, slightly erythematous plaques (areas of redness of the skin) to form on the plantar surface (sole) of the foot that are often covered by fine, powdery hyperkeratotic scales.〔〔 The vesiculobullous type of athlete's foot is less common and is usually caused by ''T. mentagrophytes'' and is characterized by a sudden outbreak of itchy blisters and vesicles on an erythematous base,〔 usually appearing on the sole of the foot. This subtype of athlete's foot is often complicated by secondary bacterial infection by ''Streptococcus pyogenes'' or ''Staphylococcus aureus''.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Athlete's foot」の詳細全文を読む スポンサード リンク
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