Alopecia areata
Alopecia areata
What is alopecia areata?
Alopecia is a general term for hair loss. Alopecia areata is a common cause of non-scarring (does not cause scarring to the scalp) hair loss that can occur at any age. It usually causes small, coin-sized, round patches of baldness on the scalp, although hair elsewhere such as the beard, eyebrows, eyelashes, body, and limbs can be affected. In some people larger areas are affected and occasionally it can involve the whole scalp (alopecia totalis) or even the entire body and scalp (alopecia universalis).
It is not possible to predict how much hair will be lost. Regrowth of hair in typical alopecia areata is usual over a period of months or sometimes years but cannot be guaranteed. The chances of the hair regrowing are better if less hair is lost at the beginning. Most people, with only a few small patches get full regrowth within a year. If more than half the hair is lost, then the chances of a full recovery are not good. The hair sometimes regrows white, at least in the first instance. Most people get further attacks of alopecia areata. In alopecia totalis and alopecia universalis, the likelihood of total regrowth is less.
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What causes alopecia areata?
Hair is lost because it is affected by inflammation. The cause of this inflammation is unknown; it is thought that the immune system, the natural defence which normally protects the body from infections and other diseases, may attack the growing hair. Why this might happen is not fully understood, nor is it known why only localised areas are affected and why the hair usually regrows again.
Someone with alopecia areata is slightly more likely than a person without it to develop other autoimmune conditions such as thyroid disease, diabetes, lupus, and vitiligo (white patches on the skin), although the risk of getting these disorders is still very low. If you have other symptoms, then discuss these with your doctor. Your doctor may suggest a blood test.
Alopecia areata is not catching and no connection has been made with food or vitamin deficiencies. Stress occasionally appears to be a trigger for alopecia areata, but it is possible that this link may be coincidental as many of those affected have no significant stress.
Is alopecia areata hereditary?
There is a genetic predisposition to alopecia areata. About 20% of people with alopecia areata have a family history.
What are the symptoms?
There may be a tingling sensation in the scalp. It can be a very upsetting condition, especially if the bald area cannot be disguised by hairstyle.
If alopecia areata affects the eyelashes, then the eyes may become sore due to dust, particularly in dry and windy conditions.
What does alopecia areata look like?
Typically, it starts as one or more bald, smooth patches on the scalp, which are not inflamed or scaly. It tends to affect the pigmented hair so there may be some white hairs left within the bald area in older people. Sometimes, the hair loss is diffused rather than well-circumscribed patches. Short, tapered hairs, known as exclamation mark hairs that are characteristic of alopecia areata, may be seen at the edge of the bald patch. Regrowth usually starts at the centre of the bald patch with fine white hair that thickens with time and usually regains its colour. Some people with alopecia areata develop small pits on their nails, similar to the dimples seen on a thimble.
Animation by Stacy Bias, based on real-life interviews conducted by Goldsmiths anthropologist, Emma Tarlo. For further understanding of the social dimensions of hair, see her book, Entanglement: The Secret Lives of Hair.
Can it be cured?
No, alopecia areata cannot be cured. Depending on the extent of hair loss there is a good chance that, for 4 out of 5 affected people, complete regrowth will occur within 1 year without treatment. There may, however, be further episodes of hair loss in the future. If there is very extensive hair loss from the start, the chances of it regrowing are not as good. Those with more than half the hair lost at the beginning or with complete hair loss at any stage have only about a 1 in 10 chance of full recovery. The chances of regrowth are not so good in young children and those with the condition affecting the hairline at the front, side or back.
How can alopecia areata be treated?
People with mild early alopecia areata may need no treatment, as their hair is likely to come back anyway without it. Some treatments can induce hair growth, though none is able to alter the overall course of the disease. Any treatments that carry serious risks should be avoided, as alopecia areata itself has no adverse effect on physical health.
Steroid creams and scalp applications
Corticosteroid creams and scalp applications. These are applied to the bald patches, usually twice a day, for a limited time.
Local steroid injections
Local steroid injections. These can be used on the scalp and brows and are the most effective approach for small patches of hair loss. Injections can be repeated every four to six weeks and are stopped once regrowth is achieved. A small dimple may develop at the injection sites, but this usually recovers after a few months. Special care is taken around the eyes, when injecting the brows, as injecting too much may cause glaucoma (raised pressure inside the eyeball).
Corticosteroid tablets.
Large doses of steroid tablets may result in regrowth of the hair, but when the treatment stops the alopecia often recurs. Taking steroids by mouth over a period of time can cause many side effects including raised blood pressure, diabetes, stomach ulcers, cataracts, and osteoporosis as well as weight gain.
Dithranol cream
This cream, which is usually used to treat a skin condition called psoriasis, causes irritation of the skin, and occasionally this appears to stimulate the hair to regrow when applied to the bald areas. There is only weak evidence for this, but it is safe to use so doctors may offer it. Dithranol stains the skin and hair a purple-brown colour, which is particularly prominent in blond and fair-headed people.
Contact sensitisation treatment
This involves making the patient allergic to a substance (usually a chemical called diphencyprone) and then applying very weak strengths of this chemical to the bald patches, usually once a week to maintain a mild inflammation. Side effects of possible itching, blistering and enlarged glands in the neck can be troublesome. Some people can get widespread eczema. Loss of skin colour (depigmentation) may develop, so it is used with caution in those with dark skin. This treatment is only available in specialised centres.
Ultraviolet light treatment (PUVA)
Ultraviolet light treatment (PUVA). This involves taking a tablet or applying a cream that makes the skin sensitive to light, and then exposing the bald patches to ultraviolet light, two or three times a week for a number of months. Relapse of alopecia is common when the treatment is stopped. There is also a possible long-term risk of skin cancers.
Minoxidil lotion
This is available over the counter. Applied to bald patches it may help some people, but the hair is often fine and not of much use.
Immunosuppressant tablets
These tablets include sulfasalazine, methotrexate, ciclosporin, and azathioprine. They suppress the immune system and are occasionally used to treat severe alopecia areata which have not responded to other treatments. The evidence that they can cause hair regrowth in alopecia areata is limited and these tablets can have potentially serious side effects.
Prostaglandin analogs
This includes eye drops, Latanoprost and Bimatoprost which may cause hair growth on eyelids however, further studies are needed to confirm its effect on scalp alopecia.
Tofacitinib and ruloxitinib
Tofacitinib, ruxolitinib and baricitinib are potentially new immunosuppressive tablets for alopecia areata. Treatments are not yet available as further studies are needed to confirm their beneficial effects for alopecia areata. Furthermore, topical formulations of these medicines are also being studied for their effectiveness in treating alopecia areata.
What if I need a wig?
Some individuals with alopecia areata will prefer to wear a wig while they wait for recovery. These can either be bought privately or obtained through the NHS on a consultant’s prescription (a financial contribution is usually required in England). Your local hospital orthotic (surgical appliances) department will be able to advise you on the range of hairpieces available on the NHS and can recommend local suppliers who are sensitive to the needs of individuals with alopecia areata.
What can I do?
- You may find that joining a patient support group (see below) and meeting other people with alopecia areata will make it easier for you to adjust to your condition.
- Some men and a few women with extensive alopecia find that shaving off the remainder of the hair provides a good solution.
- Remember that an important function of hair is to protect the scalp from sunlight. You should cover your bald patches with a sun block or a hat to prevent sunburn and also to reduce the chances of developing long-term sun damage.
- The hair also acts as an early warning to prevent scraping the scalp on low doors, cupboards, or trees. Be particularly careful to avoid hurting yourself in these situations.
- If you find that the regrowing hair is slow to recolour, it can be dyed after discussing with a good hairdressing salon.
- A few people with longer hair find hair extensions to help camouflage the problem. Some hairdressers become experts at this. It is important to avoid too much tension on any hair when this is done because this could cause hair loss, called traction alopecia.
- Artificial eyelashes, eyebrow pencils and eyebrow tattoos can help some people with problems in these areas.
Images DermNetNZ.