What condition is characterized by sudden hair loss in round patches?

Alopecia Areata is characterized by sudden hair loss that occurs in round patches on the scalp or other areas of the body. This autoimmune condition leads to the immune system mistakenly attacking hair follicles, resulting in hair falling out in these distinct circular patches. The exact cause of Alopecia Areata is not fully understood, but it is believed to involve genetic and environmental factors that trigger the immune response.

In contrast, the other conditions listed do not present with the same sudden and localized hair loss. Telogen Effluvium involves diffuse thinning of hair due to a disturbance in the hair growth cycle, typically following stress, hormonal changes, or other triggers. Androgenic Alopecia is a hereditary pattern of hair thinning and balding, often associated with aging, which usually progresses gradually rather than causing sudden patches of hair loss. Traction Alopecia results from excessive tension or pulling on the hair, often due to certain hairstyles, leading to gradual hair loss along the hairline or areas subjected to strain but not in round patches. Thus, Alopecia Areata stands out as the condition that specifically features the distinct round patches of hair loss.