Alopecia areata is hair loss of unknown cause, characterized by round patches of complete baldness.
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.
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
- Contact sensitization treatment
- Irritating agents may be applied
- hairless areas to promote regrowth
- making the patient allergic to a substance
- chemical called diphencyprone
- applying this chemical to the bald patches
- once a week to maintain a mild inflammation
- Side effects itching, blistering and enlarged glands in the neck
- Some people can get widespread eczema
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.
On occasion, a scalp biopsy may be performed.
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.
Permanent hair loss is a possible complication of alopecia areata.