ALOPECIA AREATA
Among all hair disorders, none arouse as much interest as alopecia areata. The reason for this is the uniqueness with which the disease presents itself:
1. It can occur at any age, right from infancy up to the 80’s.
2. It can affect any part of the body.
3. It can be extremely rapid leading to complete loss of scalp hair in a time span as short as 15 days or limit itself to just one patch which can remain throughout a person’s life.
4. It has phases of remissions and relapses even whilst the patient is on medication, and in few rare cases is known to relapse even 20 years after the first episode.
5. There is lack of knowledge about its exact cause and mechanism , leading to a lot of odd treatments like application of lime, detergent based washing powder, ginger , scraping with sharp objects like blades etc. Not to mention that these only cause further damage to the scalp. All in all a truly maverick disorder.
The Mechanism
Alopecia areata is an auto immune disorder. It is believed that due to certain external and internal causes, the body’s immune system is so alerted that is falsely interprets hair as a foreign body(like bacteria or virus ) and attacks the hair follicle. The hair follicle thus damaged leads to loss of hair and prevention of any further growth.
Specifically there are certain types of white blood cells which are believed to be the cause.
What are the causes of alopecia areata?
1. Emotional stress: it is believed that stress is the most common cause of alopecia areata. Although the exact mechanism is unknown, scientists believe that emotional stress affects body immunity, which in turn can damage hair follicle.
2. Local scalp infections: Infections by the lichen group of fungus is known to cause intractable cases of alopecia areata.
3. Prior/recurrent infections: Many patients with alopecia areata often give a history of recurrent infections in the past
4. Genetics: alopecia areata is a polygenic disorder. This means that there are a number of genens which determine its development. This is why we can trace a family history in some patients, but not all. Overall genes are not considered to play a significant role in alopecia areata.
Classification of alopecia areata:
Depending on the extent of spread of this condition, it is classified as follows.
1. Alopecia areata: This describes the condition when it is limited to a single or multiple patches on the scalp or anywhere on the body. This is further classified in to
-Non scarred alopecia areata: This type is only due to auto immune reasons and there is no superadded infection on the scalp.
-Scarred alopecia areata: This is mainly due to lichen infection on the scalp which is irreversibly damages the follicles and the skin of the scalp making it look like scar tissue.
2. Alopecia Totalis: This describes the condition when there is complete loss of hair from the entire sclap.
3. Alopecia universalis: This describes the condition when there is a complete loss of hair from the entire body.
Treatment:
a. Non scarred alopecia areata: The prognosis of this condition is very good. Most of the patients recover from the patches to such extent that it becomes difficult to know where it had appeared in the first place. However as explained earlier the maverick nature of this disease means that even during treatment it never disappears at once. The patches tend to fluctuate in size and number before they disappear completely. There have been medically recorded cases where relapses have occurred even years after the initial cure.
b. Scarred alopecia areata: in these cases the prognosis is not very good. The lichen infection tends to destroy the hair follicles and the skin completely in the infected area. In most cases the further spread of the disease is limited through the treatment however unlike non scarred alopecia areata re-growth is seldom possible.
Other rarer types of hair lose are:
a. Telogen effluvium
This condition usually occurs after an episode of sudden, severe stress. There is a noticeable shedding of hair which is delayed to three to four or even five to six months after the event. The event can be a heart attack, severe illness with a high fever, a sudden weight change or a major surgical procedure.
b. Trichoptilosis
It is the longitudinal splitting of hair. Also known as ‘split ends’ this condition develops after the protective cuticle has been stripped away from the end of hair fibres because of over processing. Any chemical or physical trauma which weathers the hair eventually leads to splitting of hair ends. Vigorous brushing too can cause split ends.
c. Trichotelomania
Children or adults sometimes twist or pull their hair, brows or lashes until they come out. This hair pulling is sometimes a coping response to unpleasant stress and occasionally is a sign of a serious problem.
d. Generalised atrichia
The hair loss disease is caused by the ‘hairless’ gene which is a recessive gene. This means that both parents of a child with the disease must have the disease themselves or at least be carriers for the defective gene. Because of this, generalised atrichia is an extremely rare form of hair loss.