Alopecia Areata

Alopecia areata (AA) is a common, idiopathic disorder characterized by well-circumscribed round or oval areas of nonscarring hair loss that presents with varying degrees of severity.
Alopecia totalis refers to a loss of all or almost all scalp hair and eyebrows and alopecia universalis refers to a total loss of all scalp and body hair.
AA most commonly affects young adults and children. Occasionally, a family history of AA exists.
Often, onset is attributed to recent emotional or physiologic stress.

AA is generally considered an autoimmune condition.
Biopsy findings demonstrate T-cell infiltrates surrounding the hair follicles.
AA is sometimes associated with other autoimmune disorders, such as vitiligo, thyroid disease (Hashimoto thyroiditis), pernicious anemia, and celiac disease.

AA most commonly presents as oval, round, or geometric patches of alopecia (Fig. 19.4).
Lesions are most often found on the scalp, eyebrows, eyelashes, and areas of the face that bear hair, such as the beard (Fig. 19.5) or mustache on men.
On occasion, a hand lens may reveal tiny “exclamation mark” hairs at the periphery of lesions.
Increased friction or “stickiness” (not the expected smoothness) is felt on palpation of lesional skin because of the loss of vellus hairs (Fig. 19.6).
Rarely, the entire scalp is involved (alopecia totalis), or even the entire body including pubic, axillary, and nasal hair is affected (alopecia universalis) (Fig. 19.7A,B).
Infrequently, nails may demonstrate a characteristic pitting (“railroad tracks”).
Early on there is usually asymptomatic shedding of hair, which is often discovered by the patient's hairdresser or a family member.
Frequently, hair spontaneously regrows; however, a recurrence of hair loss may be seen in 30% of patients who had experienced regrowth. Regrowing hair is initially thin and sometimes white (vitiliginous) (Fig. 19.8).
Extensive scalp involvement, an atopic history and chronicity have a poorer prognosis. Also AA that occurs as bands along the hairline margins termed the “ophiasis pattern” is more difficult to treat (Fig. 19.9).

The diagnosis of AA is generally based on its clinical appearance; however, a scalp biopsy may be performed if the diagnosis is in doubt.

Differential Diagnosis

Tinea Capitis (Discussed in Chapter 9: Hair and Nail Disorders)

Seen most frequently in African-American children and uncommonly in African-American adults.
The scalp is often scaly, itchy, and inflamed and black dots, representing broken hairs may be seen within the alopecic patches.
The diagnosis is confirmed when the KOH examination is positive for hyphae and/or spores or when a fungus grows on Sabouraud medium.

Telogen Effluvium (see below)

Trichotillomania (Compulsive Hair Pulling)

Secondary Syphilis

Secondary syphilis should always be considered in cases of unexplained patchy hair loss.
The hair loss is referred to as appearing “moth-eaten.”

Also consider:

Traction Alopecia and Hot-Comb Alopecia (Discussed below)

Management

Because mild cases of AA often show spontaneous regrowth, therapy is often unnecessary.
Both alopecia universalis and alopecia totalis are generally refractory to therapy and usually last a lifetime; spontaneous regrowth is rare.
The daily application of a potent or superpotent topical steroid, such as Lidex (fluocinonide 0.05% ointment) or clobetasol 0.05%, ointment may speed hair regrowth. To increase drug penetration, the topical steroid may be applied followed by occlusion with a plastic shower cap, and left on overnight.
If necessary, intralesional injections with triamcinolone acetonide (5 mg/cc) administered into the alopecic patches every 4 to 6 weeks is a very effective treatment option.

Further Treatment Modalities

The numerous and varied treatment modalities used for severe extensive AA reflect the fact that few are very effective. The success rates associated with the following measures have ranged from no response to varying degrees of partial success:
- Irritant therapy involves using a topical anthralin (a coal tar derivative) preparation to the alopecic areas in order to induce an inflammatory response which may drive away the perifollicular T cells.
- Immunotherapy works similarly using chemical compounds such as squaric acid or diphenylcyclopropenone (DPCP) to induce a contact dermatitis.
- The following modalities have been utilized with varying degrees of success. Topical minoxidil in a 2% to 5% concentration, scalp massage, heat, aloe vera, vitamins, hypnotherapy, oral psoralens combined with exposure to ultraviolet light in the A range (PUVA), narrow band UVB, Excimer laser, and oral immunosuppressants including cyclosporine, methotrexate, and prednisone.

Helpful Hints

Alopecia totalis and universalis, the most severe forms of AA, generally spark great emotional problems in patients and their families.
The most important part of widespread AA management is providing emotional support to the patient.
The National Alopecia Areata Foundation is an excellent resource for information and can direct patients to AA support groups and information about wigs, for example. It can be reached at: National Alopecia Areata Foundation, 14 Mitchell Boulevard, San Rafael, CA 94903; phone number: 415.472.3780; web site: http://www.naaf.org/default2.asp.

Point to Remember

Consider workup for other autoimmune diseases (e.g., thyroid disease) especially if there is an associated family history or if suggested by the review of systems or the physical examination.

SEE PATIENT HANDOUT “Alopecia Areata” IN THE COMPANION eBOOK EDITION.