Alopecia areata means loss of hair or baldness, it is a condition in which hair is lost from some or all areas of the body, usually from the scalp. Alopecia areata is most common in people younger than 20, but children and adults of any age may be affected. Women and men are affected equally.
Commonly, alopecia areata involves hair loss in one or more round spots on the scalp.
- Hair may also be lost more diffusely over the whole scalp, in which case the condition is called diffuse alopecia areata.
- Alopecia areata monolocularis describes baldness in only one spot. It may occur anywhere on the head.
- Alopecia areata multilocularis refers to multiple areas of hair loss.
- Ophiasis refers to hair loss in the shape of a wave at the circumference of the head.
- The disease may be limited only to the beard, in which case it is called alopecia areata barbae.
- If the patient loses all the hair on the scalp, the disease is then called alopecia totalis.
- If all body hair, including pubic hair, is lost, the diagnosis then becomes alopecia universalis.
- Alopecia areata totalis and universalis are rare.