Alopecia areata

Author: Honorary Associate Profesor Amanda Oakley, Dermatologist, Hamilton, New Zealand, 1997. Updated December 2015.

What is alopecia areata?

The term alopecia means hair loss. In alopecia areata, one or more round bald patches appear suddenly, most often on the scalp. Alopecia areata is also called autoimmune alopecia.

Who gets alopecia areata?

Alopecia areata can affect males and females at any age. It starts in childhood in about 50%, and before the age of 40 years in 80%. Lifetime risk is 1–2% and is independent of ethnicity.

What causes alopecia areata?

Alopecia areata is classified as an autoimmune disorder. It is histologically characterised by T lymphocytes around the hair follicles. These CD8(+)NK group 2D-positive (NKG2D(+)) T cells release pro-inflammatory cytokines and chemokines that reject the hair. The exact mechanism is not yet understood.

The onset or recurrence of hair loss is sometimes triggered by:

What are the clinical features of alopecia areata?

Several clinical patterns are described. More severe disease is associated with young age, concurrent atopic eczema, and chromosomal abnormalities.

Most patients have no symptoms, and a bald patch or thinning hair is noted incidentally, often discovered by a hairdresser. Other patients describe a burning, prickly discomfort in the affected areas—this is known as trichodynia.

Patchy alopecia areata

Patch alopecia areata can affect any hair-bearing area, most often the scalp, eyebrows, eyelashes and beard.

Patchy alopecia areata has three stages.

  1. Sudden loss of hair
  2. Enlargement of bald patch or patches
  3. Regrowth of hair

The bald areas may have a smooth surface, completely devoid of hair or with scattered “exclamation mark” hairs.

More images of alopecia areata ...

Alopecia totalis

Alopecia universalis

Ophiasis

Diffuse alopecia areata

Alopecia areata of the nails

Complications of alopecia areata

Alopecia areata patients are at risk for psychosocial consequences of their disease, such as depression and anxiety.

They should be assessed for atopy, vitiligo, thyroid disease, and other autoimmune conditions.

How is alopecia areata diagnosed?

Alopecia areata is diagnosed clinically. Although usually straightforward, additional tests are sometimes needed to confirm the diagnosis.

What is the treatment for alopecia areata?

There is not yet any reliable cure for alopecia areata and other forms of autoimmune hair loss. Because spontaneous regrowth is common in alopecia areata, and research has often been of poor quality, the effectiveness of reported treatments is mostly unknown.

Topical treatments

Several topical treatments used for alopecia areata are reported to result in temporary improvement in some people. The hair falls out when they are stopped. These include:

Intralesional corticosteroid injections

Injections of triamcinolone acetonide 2.5–10 mg/ml into patchy scalp, beard or eyebrow alopecia areata may speed up regrowth of hair. Its effect is temporary. If bald patches reappear, they can be reinjected.

Systemic corticosteroids

Oral and pulse intravenous steroids in high dose can lead to temporary regrowth of hair. Most physicians agree that long-term systemic steroid treatment is not justified because of potential and actual adverse effects.

Immunotherapy

The sensitizing agents diphenylcyclopropenone (diphencyprone) and dinitrochlorobenzene provoke contact allergic dermatitis in treated areas. These sensitisers can be reapplied once weekly to bald areas on the scalp. The resultant dermatitis is irritating and may be unsightly. It is often accompanied by a swollen lymph gland.

Other treatments

A combination of the lipid lowering agents simvastatin and ezetimibe (which have immunomodulating effects) has been reported to be effective.

There is no convincing data to support the use of methotrexate, sulfasalazine, azathioprine, ciclosporin or phototherapy.

JAK inhibitors

Several patients with severe alopecia areata have had improvement when treated with oral tofacitinib or oral ruxolitinib, which are Janus kinase (JAK) inhibitors. It is thought they may act by blocking interleukin (IL)-15 signalling. Watch out for the results of clinical trials of these biologic medicines.

What else should be considered for alopecia areata?

Counselling

Some people with alopecia areata seek and benefit from professional counselling to come to terms with the disorder and regain self-confidence.

Camouflaging hair loss

Scalp

A hairpiece is often the best solution to disguise the presence of hair loss. These cover the whole scalp or only a portion of the scalp, using human or synthetic fibres tied or woven to a fabric base.

Styling products include gels, mousses and sprays to keep hair in place and add volume. They are reapplied after washing or styling the hair.

Eyelashes

Artificial eyelashes come as singlets, demilashes and complete sets. They can be trimmed if necessary. The lashes can irritate the eye and eyelids. They are stuck on with methacrylate glue, which can also irritate and sometimes causes contact allergic dermatitis.

Eyeliner tattooing is permanent and should be undertaken by a professional cosmetic tattooist. The colour eventually fades and may move slightly from the original site. It is extremely difficult to remove the pigment, should the result turn out to be unsatisfactory.

Eyebrows

Artificial eyebrows are manufactured from synthetic or natural human hair on a net that is glued in place.

Eyebrow pencil can be obtained in a variety of colours made from inorganic pigments.

Tattooing can also be undertaken to disguise the loss of eyebrows, but tends to look rather unnatural because of the shine of hairless skin.

How can alopecia areata be prevented?

We do not yet know how to prevent the onset of alopecia areata.

What is the outlook for alopecia areata?

In 80% of patients with a single bald patch, spontaneous regrowth occurs within a year. Even in the most severe cases of alopecia totalis and alopecia universalis, recovery may occur at some future date.

Poor prognostic factors include:

New monoclonal antibody biologic agents targeting cytokine pathways offer promise for future treatment of alopecia areata.

Related information

Make a donation

Donate Today!