Alopecia areata

Definition

Alopecia areata is hair loss of unknown cause, characterized by round patches of complete baldness.

Causes, incidence, and risk factors

The specific cause of alopecia areata is unknown. A family history of alopecia is present in about a fifth of all cases. Alopecia areata is occasionally associated with autoimmune diseases.

Alopecia may also occur as alopecia totalis with complete loss of scalp hair or as alopecia universalis with total loss of all body hair.

Symptoms

The primary symptom of alopecia areata is roundish patches of hair loss on the head, with smooth, hairless scalp in the affected areas. Alopecia totalis involves the complete loss of all scalp hair, and alopecia universalis is characterized by the complete loss of all scalp and body hair.

Hairs that look like exclamation points are sometime seen at the edges of a bald patch.

Signs and tests

On occasion, a scalp biopsy may be performed.

Treatment

No fully effective treatments are available. Typical therapy includes:

• Topical corticosteroids (medium to very high potency)
• Subcutaneous (under the skin surface) steroid injection
• Ultraviolet light therapy

Irritating agents may be applied to hairless areas to promote regrowth

Expectations (prognosis)

Full recovery of hair is common. However, alopecia areata occurring at a young age, prolonged alopecia, or the presence of eczema (atopic dermatitis) often predicts a poorer outcome.

Complications

Permanent hair loss is a possible complication of alopecia areata.

Calling your health care provider

Call for an appointment with your health care provider if you are concerned about hair loss.

Illustrations

Alopecia areata with pustules

Alopecia totalis - back view of the head

Alopecia totalis - front view of the head

Alopecia, under treatment

Page Content:

Alopecia totalis; Alopecia universalis ; alopecia universalis; alopecia areata universalis; alopecia totalis; alopecia areata totalis; alopecia capitis totalis