Alopecia Areata
By Madiha ZaidI

September is Alopecia Awareness Month.

Alopecia Areata is a common condition which presents with hair loss in the form of round bald patches. The most common site is the scalp, although it can affect any hair-bearing area of the skin. The extent of hair loss can vary, ranging from localized alopecia (coin-sized to being diffuse (involving the entire scalp and/or other areas of the body). Alopecia Areata equally affects both males and females at any age; 40-50% of individuals are seen with its onset before 21 years of age, while 20% develop it after 40 years of age. Although both males and females have the same probability of acquiring this condition, certain individuals are deemed to be at a higher risk. Patients who have a family history of alopecia aerate or another autoimmune disease are more likely to be affected. Similarly, those who have chromosomal disorders such as Down syndrome, Turner Syndrome, or Patau Syndrome are more likely as well.

Alopecia Areata has been classified as an autoimmune disorder in which the T-cells surrounding the hair follicles release cytokines, which ultimately cause rejection of the hair. The condition can be brought upon by many factors such as trauma to the site, hormonal changes, viral infections, as well as emotional stress.

This condition can be further classified into several subtypes:
Patchy Alopecia Areata can affect any hair-bearing part of the skin. It comprises of three distinct stages: sudden loss of hair, bald patches continue to enlarge, and regrowth of hair. Particularly on the scalp, the bald patches have a smooth surface seen with a pathognomonic ‘exclamation mark’ hairs. The exclamation mark hairs are approximately 2-3 mm in length and can be broken or tapered, with a distinct ‘club-shaped’ root. During the third stage when the hair starts to regrow, it can initially be wither white or grey as well as curly. The regrowth of the hair can vary from patient to patient, although it can take anywhere between several months to a couple of years.
Alopecia Totalis affects approximately 5% of individuals and is seen with the complete loss of hair on the scalp.
Alopecia Universalis affects less than 1% of individuals and is commonly seen with the loss of hair on the entire body.
Ophiasis is a type of alopecia areata which primarily affects the occipital and lateral aspects of the scalp.
Diffuse Alopecia Areata which is also referred to as ‘alopecia areata incognita’ is seen with a sudden complete loss of hair.
Alopecia Areata of the nails can affect up to 10-15% of individuals, which is often seen with pitting and ridges on the nails.

Alopecia Areata is diagnosed clinically, although in chronic cases the need to do a fungal culture or a scalp biopsy may be necessary. Past medical history which is specifically seen with the appearance of bald patches is highly indicative of alopecia areata.

The treatment of alopecia areata can vary from patient to patient because, in approximately 50% of patients, the hair will spontaneously grow back within a year and will therefore not require any form of treatment. It is highly recommended that patients take precautions when going outdoors, such as protecting the exposed scalp skin with a hat, from sun damage.

Currently, the first-line treatments for alopecia areata are intra-lesional corticosteroids and topical immunotherapy. The intra-lesional corticosteroids are usually administered every 2-6 weeks and stimulate the regrowth of hair. Side effects associated with this are pain, atrophy as well as depigmentation of the skin. Topical corticosteroids are useful in some patients, although there hasn’t been a significant difference recorded between the administration of a placebo and a topical corticosteroid in the regrowth of hair.

The psychological effects exerted by alopecia areata are drastically underestimated. Professional counseling can be of great help to these patients and provide them with the tools to regain their self-confidence.

References:
1. https://dermnetnz.org/topics/alopecia-areata/

2. Harries MJ, Sun J, Paus R, King LE Jr. Management of alopecia areata. BMJ. 2010;341:c3671. Published 2010 Jul 23. doi:10.1136/bmj.c3671