Alopecia areata - an autoimmune condition

Alopecia areata affects about 2 % of the world's population.  Most people with alopecia areata develop a small circular area of hair loss such as the individual in the left photo. In such patients, the hair often grows back spontaneously.  The hair growth can be helped by use of cortisone or cortisone injections. Individuals with many circular areas of hair loss or with extensive scalp hair loss (such as alopecia totalis and alopecia universalis) are less likely to experience spontaneous growth and treatment may be considered if any regrowth is to  occur.

Alopecia areata is an autoimmune disease.  The word "auto" means "self" and the word immune refers to the  "immune system". Alopecia areata is a condition whereby the individual's own immune system reacts to its own hair.

Normally, our immue system is designed to attack bacteria and viruses as our main line of defence from the outside world.  Our immune system also kills some types of cancer cells.  The immune system is complex and has dozens of other roles too. However, when a patient has an autoimmune disease, the immune system also targets a specific part of the patient's own body. 

In the case of alopecia areata, the immune system is targetting the patient's hair follicles. Inflammation develops around the hairs and this causes the hair to fall out. The photo on the right shows that the inflammation develops at the very bottom of the hair follicle - around a region called the 'bulb.'  Cortisone medications and cortisone injections help to"chase away" the inflammation around the bulb and help to get the hairs back in a growing mode.

If you have questions about alopecia areata, visit our Frequently Asked Questions section.

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