Most hair follicles on the scalp do not produce hair continuously. The follicles may be in either of the three stages of the hair cycle : Anagen (growing), Catagen ( falling) and Telogen (resting) phase. There may be a temporary or permanent loss depending on various multiple conditions & diagnoses. They are listed under different names like scarring alopecia, alopecia areata, anagen effluvium, telogen effluvium, etc. The various types of hair loss are being listed below to know the real root cause.
Alopecia Areata is thought to be an auto-immune disease of the hair, initially appearing as a rounded bare patch about an inch across. It affects both men and women equally and may be experienced first in childhood. Many people affected with Alopecia Areata will only have one experience of loss with re growth occurring afterwards. There are three types of Alopecia Areata which are named according to their severity. • Alopecia Areata is mild patchy hair loss on the scalp • Alopecia Totalis is the loss of all scalp hair • Alopecia Universalis is the loss of scalp and all body hair Researchers believe that Alopecia Areata is an auto-immune disease; this means that the body’s immune system acts as if the hair follicles are foreign and attacks them. White blood cells called T-lymphocytes attack the hair follicle which causes the hair to stop growing and enter into the telogen (resting) phase, then about 3 months later, when the resting phase is over the hair will then fall out. Only when T-lymphocytes stop attacking the hair follicle, will new hair grow.
Male and female pattern baldness (androgenetic alopecia) is the most common forms of hair loss. It can affect both men and women although men experience a much greater degree of loss. In women, Androgenetic Alopecia appears as diffuse hair loss occurring over most of the scalp. In men, the pattern of loss usually starts with a receding hairline which then advances to thin the top of the head. After a lot of research, it is now known that it is more specifically the male hormone dihydrotestosterone (DHT) – ( produced by the action of enzyme 5 alpha reductase on testosterone) which contributes to Androgenetic Alopecia in those who are genetically predisposed. It is interesting to note that individuals with a deficiency in 5 alpha reductase do not develop Androgenetic Alopecia. This is because the body is unable to convert testosterone into dihydrotestosterone. When Androgenetic Alopecia occurs large active hair follicles in specific areas begin to change to smaller less active ones that shrink slightly with each new growth cycle. If an individual has androgenetic alopecia the overall levels of testosterone may be normal however the activity of 5 alpha reductase is greater than normal which results in increased amounts of dihydrotestosterone in the hair follicle.
Telogen Effluvium occurs when sudden or severe stress causes an increase in the shedding of the hair. Doctors seem to agree that telogen effluvium is probably the second most form of hair loss seen by dermatologists. In Telogen effluvium, a sudden or stressful event can cause the hair follicles to prematurely stop growing and enter into a resting phase. This occurs when there is a change in the number of hair follicles growing hair. If the number of hair follicles producing hair drops drastically for any reason during the resting, or telogen phase, there is a significant corresponding increase in dormant, telogen stage hair follicles. Accordingly the result is shedding, or effluvium hair loss. This will then appear as diffuse thinning of hair on the scalp, which may not be even all over. This can be more severe in certain areas of the scalp more than others. Interestingly, most hair on top of the scalp thins a lot more than it does at the back and sides of the scalp. There is generally no hair line recession, except in a few chronic cases that are rare.
When inflammation of the hair follicles occurs due to infection it can lead to Scarring Alopecia. While many forms of scarring alopecia exist, a common theme is a potentially permanent and irreversible destruction of hair follicles and their replacement with scar tissue. Most forms of scarring alopecia occur first as small patches of hair loss that may expand with time. In some cases hair loss is gradual, without noticeable symptoms, and can go unnoticed for a long time. In other instances, hair loss is associated with severe itching, burning, and pain, and progresses at a rapid pace. The early stages of scarring alopecia can have inflammatory cells around the hair follicles, which may induce destruction of the hair follicles and development of scar tissue. Visual indicators may help with diagnosis, but to diagnose a scarring alopecia, a skin biopsy is confirmatory. It will not only help to diagnose scarring alopecia but also any other cause as well. A small piece of 2 to 4 mm diameter is taken and examined carefully under a microscope.
Dermatologists describe this as a condition of no hair growth. This condition is wholly unlike alopecia which describes hair loss where formerly there was hair growth; hypotrichosis describes a situation where there wasn’t any hair growth in the first place. Hypotrichoses are conditions affecting individual’s right from birth and usually stay with them throughout their lives. They mostly occur as a result of genetic aberrations or defects of embryonic development. There are usually hundreds of types of genetic hypotrichoses. Often, individuals affected have other physical or mental problems that are way beyond just a lack of hair.
Congenita is a rare disorder that often results as a small blistered atrophied area usually in the midline of the scalp and present from birth. In most cases, the problem heals itself. However, in larger areas it may be associated with underlying developmental disorders. Babies may be born with a patch of skin like an open wound or an ulcer. This defect often occurs at the back of the scalp, at the center of hair growth. If the defect is small, the skin will scab over and the baby is left with a scar. This sometimes happens in the womb and all seen at birth is scalp patch where there are no hair follicles. This is often done with some urgency, since the open wound is a site of potential hemorrhage and infection. The quicker the defect heals, the better.
Triangular alopecia is similar to congenital aplasia. It is apparent from birth and tends to affect a triangular patch of skin and hair above temples. For largely unknown reasons, the skin essentially does not grow hair follicles in this area in a few people. Affected areas can be surgically removed or implanted with hair follicles taken from elsewhere on the scalp.
Congenital atrichia is another condition in hair loss patterns. This was the first human hair loss disease researchers determined that was caused by a single gene defect. Generally regarded as a hypotrichosis, this is not strictly so. Congenital Atrichia occurs when a baby is born without hair follicles in certain areas. This can be quite common and usually only occurs in a few spots. In early childhood they lose all their hair, and it never re-grows.
For the hair, ringworm scalp usually begins as a small pimple to progressively expand in size, leaving scaly patches of temporary baldness. The fungus gets into hair shafts. This is the typical way that ringworm operates. In the affected area, hair become brittle and break off easily leaving only a bald patch of skin. Affected areas are often itchy, red and inflamed, scaly patches may blister and ooze. The patches are usually redder around the outside with a more normal skin tone in the center. This may eventually create the appearance of a ring, hence the name, ringworm. Ringworm is believed to be contagious. It can be passed from one person to the next by direct skin-to-skin contact. You can also catch ringworm through contact with contaminated items such as combs, unwashed clothing, and shower or pool surfaces.
Folliculitis refers to focal inflammation of hair follicles. It generally looks like acne with little rings of inflammation to surround opening of a hair follicle. The whole thing works in stages. In the early stages, the hair shaft may still be present in the middle of folliculitis, but as it progresses hair falls out often. When it is severe, the inflammation is generally intense enough to permanently destroy hair follicles, leaving small bald patches. Variations of folliculitis exist which are non-infectious like those caused by oils and greases applied to the skin that clog up hair follicles, but is usually due to a bacterial infection.
Anagen Effluvium – Cancer Treatment Hair Loss:
Anagen Effluvium is the sudden hair loss which occurs as a result of Chemotherapy or Radiation Treatment given for Cancer treatment. In Anagen Effluvium the hair does not enter a resting stage as is does with Telogen Effluvium. The hair loss is usually sudden occurring 1 to 3 weeks after exposure to the chemicals or radiation has occurred. Cancer treatments in the form of Chemotherapy and Radiation Treatments are the most common causes of Anagen Effluvium. However, exposure to toxic chemicals such as Thallium and Arsenic may also produce a sudden loss of hair. One of the side effects of this cancer chemotherapy is that it can also stop the growth of the hair and may cause the shedding of hair. In some cases up to 90% of the hair may be affected and often the remaining 10% may also go into the resting phase. Some hair follicles do not shed the hair but produce a narrower weaker hair which breaks off easily. Sometimes when the hair grows back the texture can be different. Some people who have had curly hair have claimed that their hair has grown back straight and sometimes even the color can become different. The important thing to remember is that this hair loss is not permanent and once treatment is stopped the hair follicles will recover and the hair will grow back.