Alopecia

特許 権利維持 Alopecia areata (AA), also known as spot baldness, is an autoimmune disease in which hair is lost from some or all areas of the body, usually from the scalp due to the body's failure to recognize "self" and destroys its own tissue as if it were an invader.[1][2] Often it causes bald spots on the scalp, especially in the first stages. In 1–2% of cases, the condition can spread to the entire scalp (alopecia totalis) or to the entire epidermis (alopecia universalis). Conditions resembling AA, and having a similar cause, occur also in other species.