(See also Alopecia Alopecia Alopecia is defined as loss of hair from the body. Hair loss is often a cause of great concern to the patient for cosmetic and psychologic reasons, but it can also be an important sign of systemic... read more .)
The scalp and beard are most frequently affected, but any hairy area may be involved. Hair loss may affect most or all of the body (alopecia universalis). Alopecia areata is thought to be an autoimmune disorder affecting genetically susceptible people exposed to unclear environmental triggers. It occasionally coexists with autoimmune vitiligo Vitiligo Vitiligo is a loss of skin melanocytes that causes areas of skin depigmentation of varying sizes. Cause is unknown, but genetic and autoimmune factors are likely. Diagnosis is usually clear... read more or thyroiditis Hashimoto Thyroiditis Hashimoto thyroiditis is chronic autoimmune inflammation of the thyroid with lymphocytic infiltration. Findings include painless thyroid enlargement and symptoms of hypothyroidism. Diagnosis... read more .
Diagnosis of Alopecia Areata
Diagnosis of alopecia areata is by inspection. Alopecia areata typically manifests as discrete circular patches of hair loss characterized by short broken hairs at the margins, which resemble exclamation points. Nails are sometimes pitted, display longitudinal ridging, or display trachyonychia, a roughness of the nail also seen in lichen planus Lichen Planus Lichen planus is a recurrent, pruritic, inflammatory eruption characterized by small, discrete, polygonal, flat-topped, violaceous papules that may coalesce into rough scaly plaques, often accompanied... read more . Red lunula may also be seen.
Differential diagnosis includes tinea capitis Tinea Capitis (Scalp Ringworm) Tinea capitis is a dermatophyte infection of the scalp. Diagnosis is by clinical appearance and by examination of plucked hairs or hairs and scale on potassium hydroxide wet mount. Treatment... read more , trichotillomania Trichotillomania Trichotillomania is characterized by recurrent pulling out of one's hair resulting in hair loss. Patients with trichotillomania repeatedly pull or pluck out their hair for noncosmetic reasons... read more , traction alopecia, lupus Systemic Lupus Erythematosus (SLE) Systemic lupus erythematosus is a chronic, multisystem, inflammatory disorder of autoimmune etiology, occurring predominantly in young women. Common manifestations may include arthralgias and... read more , and secondary syphilis Secondary syphilis Syphilis is caused by the spirochete Treponema pallidum and is characterized by 3 sequential clinical, symptomatic stages separated by periods of asymptomatic latent infection. Common manifestations... read more . If findings are equivocal, further testing can be pursued with potassium hydroxide preparation, fungal culture, screening for syphilis, or biopsy. Patients with clinical findings suggesting associated autoimmune diseases (particularly thyroid disease) are tested for those diseases.
Treatment of Alopecia Areata
Sometimes topical anthralin, minoxidil, or both
Sometimes topical immunotherapy
Rarely photochemotherapy or psoralen plus ultraviolet A (PUVA)
Use of hairpieces and camouflage techniques
If therapy is considered, intralesional corticosteroid injection is the treatment of choice in adults. Triamcinolone acetonide suspension (typically in doses of 0.1 to 3 mL of 2.5 to 5 mg/mL concentration every 4 to 8 weeks) can be injected intradermally if the lesions are small. Potent topical corticosteroids (eg, clobetasol propionate 0.05% foam, gel, or ointment 2 times a day for about 4 weeks) can be used; however, they often do not penetrate to the depth of the hair bulb where the inflammatory process is located. Oral corticosteroids are effective, but hair loss often recurs after cessation of therapy and adverse effects limit use.
Topical anthralin cream (0.5 to 1% applied for 10 to 20 minutes daily then washed off; contact time titrated as tolerated up to 1 hour/day) may be used to stimulate a mild irritant reaction. Minoxidil 5% solution may be helpful as an adjuvant to corticosteroid or anthralin treatment.
Induction of allergic contact dermatitis using diphenylcyclopropenone or squaric acid dibutylester (topical immunotherapy) leads to hair growth due to unknown mechanisms, but this treatment is best reserved for patients with diffuse involvement who have not responded to other therapies.
Oral methotrexate has been successfully used for the treatment of alopecia totalis and alopecia universalis in both adult and pediatric populations. Doses range from 15 to 25 mg weekly. Methotrexate can also be used in combination with oral corticosteroids. Its use is typically reserved for refractory alopecia areata in patients who fail standard therapy (1 Treatment references Alopecia areata is typically sudden patchy nonscarring hair loss in people with no obvious skin or systemic disorder. (See also Alopecia.) This photo shows patchy loss of scalp hair in alopecia... read more ).
Systemic and topical PUVA have been used with limited success in patients who fail conventional therapy. However, this is a less favored treatment option because of high relapse rates, lack of randomized controlled trials, and increased risk of cancer with PUVA.
Alopecia areata may spontaneously regress, become chronic, or spread diffusely. Risk factors for chronicity include extensive involvement, onset before adolescence, atopy, and involvement of the peripheral temporal and occipital scalp (ophiasis).
Janus kinase (JAK) inhibitors are a new class of immunomodulator drugs (tofacitinib, ruxolitinib, baricitinib) that in small studies have shown benefit and show promise for treating alopecia areata (2 Treatment references Alopecia areata is typically sudden patchy nonscarring hair loss in people with no obvious skin or systemic disorder. (See also Alopecia.) This photo shows patchy loss of scalp hair in alopecia... read more , 3 Treatment references Alopecia areata is typically sudden patchy nonscarring hair loss in people with no obvious skin or systemic disorder. (See also Alopecia.) This photo shows patchy loss of scalp hair in alopecia... read more ).
Hairpieces and camouflage techniques can be used to mask the effects of hair loss.
1. Strazzulla LC, Wang EHC, Avila L, et al: Alopecia areata: An appraisal of new treatment approaches and overview of current therapies. J Am Acad Dermatol 78(1):15-24, 2018. doi: 10.1016/j.jaad.2017.04.1142
2. Damsky W, King BA: JAK inhibitors in dermatology: The promise of a new drug class. J Am Acad Dermatol 76(4):736-744, 2017. doi: 10.1016/j.jaad.2016.12.005
3. Bavart CB, DeNiro KL, Brichta L, et al: Topical Janus kinase inhibitors for the treatment of pediatric alopecia areata. J Am Acad Dermatol 77(1):167-170, 2017. doi: 10.1016/j.jaad.2017.03.024