Although alopecia areata is an inflammatory, autoimmune type of hair loss, it is characterized as a nonscarring type; the hair grows back in all but extremely long-standing cases. Any area of the body may be affected, including the beard area (A). The typical lesion is a circumscribed patch of hair loss in which tapered hairs are seen; these sometimes seem to float above the scalp (B). Anagen growth has been disrupted; a hair-pluck analysis may reveal hairs that resemble pencil points.
The scalp does not show scaling or redness in the areas of hair loss. Rarely, alopecia areata can have a diffuse presentation, in which the patient experiences sudden and rapid hair loss similar to that of anagen effluvium. In such cases, a skin biopsy is very valuable. In alopecia areata, a lymphocytic infiltrate around the hair bulb will be observed, unlike the picture of an anagen effluvium caused by reaction to medication.