Final answer:
Alopecia areata is an autoimmune disorder characterized by the sudden loss of hair in round patches, which may overlap, typically starting on the scalp. This condition can cause a tingling sensation or slight itching, and while it has no cure, treatments are available to manage its appearance.
Step-by-step explanation:
Alopecia areata is a health condition characterized by hair loss, which occurs when the immune system mistakenly attacks hair follicles, leading to the loss of hair on the scalp and possibly on other parts of the body. The distinguishing features of alopecia areata include small, round patches of baldness on the scalp, although the condition can affect any hair-bearing skin. The condition typically manifests as sudden hair loss that starts with one or more circular bald patches that may overlap.
Alopecia areata occurs in the anagen, or active phase of the hair growth cycle, and can affect anyone regardless of age or gender. This hair loss condition also is often associated with other autoimmune disorders, and stress can be a contributing factor. While the exact cause of alopecia areata is not fully understood, it is believed to have a genetic basis.
In addition to the visual signs of hair loss, some individuals with alopecia areata may experience a tingling sensation or a slight itching or burning sensation in the affected areas. There is currently no cure for alopecia areata, but treatments are available that may promote hair regrowth or improve the appearance of baldness.