Alopecia Areata

What is alopecia areata?
Alopecia areata is a disease of unknown cause characterized by an overactive immune system (the system of the body responsible for attacking outside invaders, such as bacteria or viruses or destroying cancer cells). Since the immune system of patients with alopecia areata is not working properly, it attacks their own hair. As a result of such an attack, hair falls out and stops growing. Alopecia areata is not contagious.

The course of this condition is unpredictable. Less initial involvement (one or two patches) is usually a good sign. Severe involvement from the start, or presence of ophiasis pattern (see below) is not a good indicator for future treatment success. The disorder most commonly presents with round patches of hair loss on scalp. Other patterns of involvement include ophiasis (hair loss on back and sides of the scalp), diffuse pattern (decreased hair density throughout scalp), alopecia totalis (total loss of scalp hair), and alopecia universalis (total loss of scalp and body hair). Nail changes (small indentations, longitudinal striations, sandpaper appearance) can also be seen in patients with alopecia areata.

Usually patients with alopecia areata experience multiple recurrences throughout their lifetime. Majority of patients have mild forms of the disease and recover completely within 1 year without treatment. Only a small minority of patients develops severe form of alopecia areata and loose a lot, or most of their hair. Additional tests are not usually required to diagnose alopecia areata. Physical exam by a dermatologist is all that is needed. In case of difficulty in establishing the diagnosis, a skin biopsy (tiny piece of skin removed from scalp and sent to the lab) may be needed.

Since the destruction of hair follicles by inflammatory cells occurs deep within the skin, topical creams or ointments are usually not effective. Minoxidil 5% solution or foam may be used in addition to other treatments, but is not usually of benefit alone.

The most common therapy for alopecia areata is skin injections of dilute corticosteroid solution. These treatments are effective in inducing hair growth within 4 to 8 weeks. Multiple injections may be needed for adequate response. Injections are best used for limited disease (one to several patches). If more severe involvement is observed, other treatments should be tried.

Sensitization therapy with squaric acid dibutyl or diphenylcyclopropenone is an option when scalp involvement is more severe. In this method, patient is made allergic to the above mentioned chemicals. Thereafter, weekly applications of squaric acid dibutyl or diphenylcyclopropenone produce redness and scaling. This “good” inflammation caused by outside chemicals is supposed to fight “bad” inflammation caused by patient’s own immune system. Similar principle is used in prescribing topical arthralin creams. These creams are irritating. They are used to induce a certain degree of inflammation which may be helpful in reversing alopecia areata.

Cyclosporine capsules may be used when everything else fails. Cyclosporin has toxic effects on kidneys, and therefore is a treatment of last resort.

Norris D. Alopecia areata: current state of knowledge. Journal of the American Academy of Dermatology. 51:S16-7, 2004 Jul.

External links

Alexander Doctoroff, D.O., F.A.O.C.D.
Assistant Chief of Dermatology,
Veterans Administration Medical Center
East Orange, New Jersey

Assistant Clinical Professor of Medicine,
University of Medicine and Dentistry of New Jersey