Alopecia Areata

Alopecia areata (AA) is an autoimmune disease that affects infants, women, and men and causes hair loss. Hair loss in AA manifests itself as tiny, round smooth patches that can fade on their own or persist for years. Some people with AA (about 5% of the population) may lose all of their scalp hair (alopecia totals) or all of their scalp and body hair (alopecia totalis) (alopecia universalist). The self-immune system targets the hair root for unexplained reasons, resulting in hair loss.