Alopecia areata - Overview
Alopecia areata is an autoimmune condition that often results in hair loss in small, circular patches of the scalp.
However, it can occasionally cause generalised baldness as well. Skin patches affected by alopecia hair loss typically occur on the scalp and beard, however, they can affect any hair on the body.
Alopecia areata affects about 0.2% of the population. It is a more common cause of sudden hair loss than androgenetic Alopecia or telogen effluvium. Both genders (women and men) are equally affected by alopecia areata.
The most prevalent type of Alopecia in kids is alopecia areata. About 15% of cases of the disease are familial, although how the disorder manifests itself varies depending on the family member.
Alopecia areata patients can lose all of their scalp hair (alopecia areata totalis) in 5% of cases, and 1% can develop alopecia areata Universalis (loss of total body hair).
Types of Alopecia areata
Alopecia areata can come in three different forms.
- Patchy alopecia areata - This type of Alopecia is the most prevalent form, which is characterised by one or more patches of hair loss in the size of coins on the scalp or in other areas of the body.
- Alopecia totalis - Baldness-affected individuals can completely or almost completely lose their scalp hair.
- Alopecia Universalis - There is a complete or nearly complete loss of hair on the scalp, face and the rest of the body with this uncommon type of Alopecia.
Causes of Alopecia areata
Inflammation
Inflammation damages the hair, which causes hair loss. The cause of the inflammation remains unknown. The most common reason is the immune system, the body's natural defence against infections and diseases. The immune system can attack or damage the hair follicles and prevent them from growing.
Autoimmune diseases
Other autoimmune problems like thyroid disease, Diabetes, lupus and vitiligo (white patches on the skin) are more likely to occur in people with alopecia areata and vice versa. A blood test might be advised by a physician for diagnosis.
There is no known link between alopecia areata and nutrient or vitamin deficiency. Alopecia areata occasionally seems to be triggered by stress, but given that many affected people experience little or no stress, it's possible that this association is only coincidental.
What does Alopecia areata look like?
Alopecia areata begins as one or more smooth, bald patches on the scalp that are neither scaly nor inflammatory. Older persons may still have some white hair in the bald area because it usually affects pigmented hair.
Sometimes there are dispersed areas of hair loss rather than clearly defined patches. The edge of the bald patch may have short, tapering hairs called exclamation mark hairs, which are a usual occurrence with alopecia areata.
At the centre of the bald patch, hair regrowth typically begins with fine, white hair that grows over time and typically takes on a new colour. Some patients of alopecia areata experience the development of tiny pits on their nails that resemble the dimples on a thimble.
Symptoms of Alopecia areata
Nail changes
Some persons have ridges and pits in their nails, especially those with more significant hair loss.
Hair changes
When alopecia areata first manifests, round or oval patches of hair on the scalp suddenly fall out. However, any portion of the body, including the beard area in men, the eyebrows, and the eyelashes, may also be affected.
Short, broken hairs or exclamation point hairs with a base that is narrower than a tip is frequently seen along the boundaries of the patch. On the exposed portions, there typically is no indication of a rash, redness or scarring.
Some claim to experience tingling, burning or itching on certain skin spots just before hair loss. The hair usually grows back, but there may be more hair loss episodes.
Risk factors of Alopecia areata
Alopecia areata affects people of various ages as well as skin and hair colours. The second and third decades of life have the highest incidence of this disease, and most individuals begin to show symptoms before the fourth decade. There is no sex or ethnicity predominance associated with Alopecia areata.
Alopecia areata risk factors include the following.
- Family history of Alopecia areata
- Chromosomal conditions like Down syndrome
- Polyglandular autoimmune syndrome type 1
- Thyroid disease and other autoimmune disorders like vitiligo
- Certain genes
How to diagnose Alopecia areata?
Alopecia areata is primarily diagnosed based on clinical symptoms.
Hair pull test
Hair pull test results are usually positive in alopecia areata and can help confirm hair loss.
Involves providing light traction while holding 40–60 tightly bunched hairs.
Positive if more than 10% of the hairs can be pulled with ease.
Trichoscopy
Using a dermatoscope, the hair follicle, hair shaft, and scalp are examined.
Exclamation point hairs, broken or dystrophic hairs, and yellow and black dots are signs of active disease.
Skin biopsy
- A skin biopsy may be necessary when the diagnosis is unclear.
- Histopathology helps diagnose acute alopecia areata, which is seen as a bee-swarm pattern of lymphocytic infiltrates encircling anagen hair follicles.
- As the condition progresses, there is a decrease in anagen follicle size and an increase in catagen and telogen follicle size.
Treating Alopecia areata
Topical creams
- Corticosteroids - Topical medications for alopecia areata are available in the form of ointments, creams or liquids with high levels of corticosteroids. When used in combination with occlusive dressings, they are beneficial.
- Minoxidil works best when administered with other treatments. This is available without a prescription. Some people may find relief when applied to bald spots, however, the hair is often thin and not very useful.
- Dithranol - Dithranol leaves a purple-brown stain on the skin and hair, which is most noticeable in those with blonde hair and a fair complexion. Since brown stains appear on the skin and hair, fair-haired people should only use them in moderation.
When applied to bald regions, hydroxyanthrone cream, often used to treat psoriasis, irritates the skin and occasionally stimulates hair regrowth. Although there exists little evidence to support it, doctors may recommend it as it is safe to use.
Steroid injections
Steroid injections are one of the best treatment options for minor bald patches and can be applied to the scalp and brows. Once regrowth is seen, injections can be paused and repeated every four to six weeks.
Although this goes away after a few months, a tiny indentation could appear at the injection sites.
When injecting the brows, extra caution is taken around the eyes because too much injection could result in glaucoma (raised pressure inside the eyeball).
Topical immunotherapy
Applying chemicals like diphenylcyclopropenone to the afflicted areas might cause allergic contact dermatitis, stimulating hair regrowth.
Potential side effects include severe dermatitis, urticaria, lymphadenopathy and depigmentation.
Contact sensitisation treatment
Contact sensitisation treatment involves making the patient allergic to a substance (often a chemical called diphencyprone) and then applying extremely small concentrations of this chemical to the bald spots, typically once every week, to sustain a minor irritation.
Itchy skin, blistering, and swollen neck glands are possible side effects. Large-scale eczema can affect some people. Patients with dark skin should be cautious since depigmentation or loss of skin colour could result.
Ultraviolet light treatment
The procedure involves taking a pill or using a cream to make the skin more sensitive to light, which is followed by exposing the bald spots to UV radiation twice or three times a week for a specific period of time. When the medication is withdrawn, relapses of the condition are frequent. Additionally, skin cancer may be a long-term risk.
Immunosuppressant tablets
Immunosuppressant tablets include ciclosporin, azathioprine, methotrexate, and sulfasalazine. These tablets work by suppressing the immune system and are sometimes used to treat severe cases of alopecia areata that have not responded to conventional treatments.
There is little evidence that these medications can help people with alopecia areata regrow hair, and they can have negative side effects that could be life-threatening.
Conclusion
Alopecia areata is a condition that results in hair loss when the immune system destroys hair follicles. The majority of patients have no other symptoms and are in good health.
Each individual's case of alopecia areata develops differently. Some people have on-and-off hair loss throughout their lifetimes, while others only experience it once. Also, recovery is unpredictable. Some people's hair will fully regrow, while others won't.
Alopecia areata cannot be cured. However, some treatments can hasten the growth of new hair. Resources are also available to assist people in coping with hair loss.
FAQs
Can hair loss be stopped?
There are medications that can be injected or applied topically, as well as phototherapy, which may hasten the reduction of this disease's side effects.
