- Alopecia areata
What is alopecia areata?
Alopecia areata (AA) is a condition where hair loss usually occurs in bald patches on the scalp, which can progress to total scalp hair loss (alopecia totalis) and can further progress to total body hair loss (alopecia universalis). The areas of hair loss are usually random and can involve hairs in any part of the body including eyebrows, eyelashes and body hair. AA can affect men, women and children of any age.
What causes alopecia areata?
AA is an autoimmune condition, which happens when the body's own immune system gets a bit "confused" and attacks its own cells instead of foreign cells like bacteria and viruses. In AA, the immune system attacks hair follicles, causing them to turn off and shed hairs. Examples of other autoimmune conditions include thyroid problems and diabetes.
It is not known how AA develops but a genetic predisposition plays a role. Many cases of AA resolve spontaneously and most that do not can be treated effectively.
What happens to hair in alopecia areata?
It is important to understand how the hair cycle works and how the immune system comes to play in AA to explain this.
In normal circumstances, each hair follicle on the scalp produces a number of hairs throughout life. Hair grows from the base of the follicle at the rate of about 1cm a month for about 3 years. This growth phase is called anagen. After anagen, the hair dies and no longer grows and simply sits dormant in the follicle for a 3-month phase called telogen. After telogen, the next anagen phase starts and hair grows out of the follicle. As it grows, it pushed the old telogen hair out. This is a cycle that continues throughout life.
In alopecia areata, the body's immune system attacks the hair bulb whilst in the anagen phase. This misdirected immune attack prevents the growth of healthy anagen hairs and pushes the affected hair follicles into a dormant telogen state. As the hair follicles are "turned off", but the ahir bulb is not destroyed, there is always a chance for recovery or regrowth. This is much in the same way that daffodils that can grow each spring providing a bulb remains in the ground.
What is the course of progression of alopecia areata?
AA may recover by itself without any treatment. Without treatment, up to a third of people affected by AA will have completely regrown their hair within 6 months and half the people within one year. However, there would be people with treatment resistant AA that persists for many years and do not respond to any treatment.
Is there a cure for alopecia areata?
No, but there are very effective treatments available for AA. The aim of treatment is to stimulate hair regrowth in the bald patches but this would not alter your genetic susceptibility to develop new bald patches in the future.
What treatments are available for alopecia areata?
In most cases, AA is treated with cortisone (steroids), which may suppress abnormal as well as normal immune responses. Steroid injections to bald patches is usually helpful, but extensive and rapidly progressive AA usually requires steroid tablets. Steroid treatment is often successful but it does not suit everyone and hair loss may reoccur when treatment is stopped.
Alternatives to steroids include topical irritant or immunotherapy applied directly to the scalp. Commonly used irritants include dithranol and salicylic acid, and commonly used immunotherapy agents include diphenylcyclopropenone (DCP). These agents function to divert the immune attacks toward the skin surface and away from the hair bulb, allowing hair to regrow. There may be mild to severe reactions to these treatments and your doctor needs to monitor you for these reactions. These treatments would need to be used for several months to achieve regrowth and are not suitable for everyone.
Another treatment alternative is PUVA therapy, which requires visits to the doctor's surgery 3 times per week for treatment with ultraviolet light.
Where can I seek help for alopecia areata?
Your first stop would be to see your general practitioner (GP) who can then refer you to a dermatologist if further advice is needed in regards to further management of AA.
Be careful of the information and advice for treatments of AA that you obtain especially from the internet. There are many bogus treatments that cost a lot of money and do not work. Always get expert medical advice before you decide on a certain treatment.
Alopecia areata support groups are usually very useful and provide excellent support for people affected by AA. They also conduct seminars and meetings for people affected by AA and their families. You can find their contact details usually on the internet.
Many thanks to the alopecia areata patient information sheet produced by the Australasian Hair and Wool Research Society.