Alopecia Areata is thought to be an auto-immune disease of the hair, initially appearing as a rounded bare patch about an inch across. Alopecia Areata affects both men and women equally and is often experienced first in childhood. According to a survey taken in America one person in every hundred is likely to experience Alopecia Areata at sometime in their life. Many people affected with Alopecia Areata will only have one experience of hair loss with regrowth occurring afterwards, however it is estimated that in approximately 20% of cases in the UK hair loss recurs or becomes permanent.
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.
Often appeared in young and middle-aged men, Seborrheic Alopecia is a common skin disease and is one of the most common hair loss issues in men. It has demonstrated oily scalp secretion and causes hair to be shiny. Seborrheic alopecia is excessive sebum that occurs in the basis of the hair. The scalp of patients with symptoms of excessive overflow of fat, are often accompanied by an increase in antidandruff, oily scalp and itchy sensations.
Androgenetic Alopecia - Male Pattern Baldness / Female Pattern Baldness
Androgenetic Alopecia accounts for 95% of all 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 however the pattern of loss usually starts with a receding hairline which then advances to thin the top of the head.
Causes of Androgenetic Alopecia
In 400 BC Hippocrates observed that eunuchs did not become bald. Later Aristotle noticed this also. In the 1940s Dr James Hamilton concluded that genetic predisposition in the present of the male hormone androgen were the factors that caused the development of Androgenetic Alopecia.
However it is now known that it is more specifically the male hormone dihydrotestosterone (DHT) which is converted from the enzyme testosterone by the enzymes 5 alpha reductase 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. The enzyme 5 alpha reductase is thought to be the major cause of this. Under the action of the enzyme the male hormone testosterone become dihydrotestosterone. This causes the hair shafts to narrow producing progressively finer hairs with each new growth cycle until eventually the hairs become transparent and stop emerging. 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.
Anagen Effluvium - Cancer Treatment Hair Loss
Effluvium is the sudden hair loss which occurs as a result of chemicals
or radiation, such as the hair loss that results during certain types
of Chemotherapy or Radiation 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 expose to the chemicals or radiation has occurred. Cancer treatments such as 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.
is used in the treatment of cancer to destroy the cancer cells which
divide rapidly within the body. One side effect of this cancer
treatment however 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% was already in the resting
phase before the treatment was started. Some hair follicles do not shed
the hair but produce a narrower weaker hair which breaks off easily.
Anagen Effluvium caused by Chemotherapy is only a temporary condition and in most cases hair growth will return to normal once treatment is finished. Many people even claim that their hair grows back healthier and thicker than before. 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.
Self Induced Hair loss
Some damage to the hair is self inflicted sometimes consciously or unconsciously the two main types of self induced hair loss are Trichotillomania and Traction Alopecia.
Trichotillomania is self induced hair loss which results from the continuous pulling or plucking of the hair. It occurs most commonly among young children, adolescents and women and effects twice as many females as males. The hair is often pulled out in distinct patches on the scalp however some individuals also pull out eyebrows and eyelashes.
The treatment for Trichotillomania often involves counseling or psychiatric help, however in some cases an antidepressant may be prescribed.
Traction Alopecia is usually caused by continuous and excessive pulling on the hair due to various types of hairstyling. Ponytails, buns, braiding and cornrows often result in a continuous pulling on the hair. This traction gradually results in hair loss. If this type of traction and hair loss continues for an excessively long period of time then the hair loss may become permanent. Generally however a change in hairstyle that reduces the traction on the hair and hair follicle is all that is required in the treatment of Traction Alopecia.
Sudden stress relate hairs loss which appears as thinning throughout the whole scalp.
Telogen Effluvium occurs when sudden or severe stress causes an increase in the shedding of the hair. In Telogen effluvium a sudden or stressful event can cause the hair follicles to prematurely stop growing and enter into a resting phase. The hair will then stay in the resting phase for about 3 months after which time a large amount of hair will be shed. Often the person involved will have recovered from the event before the hair loss occurs. In most cases the hair loss is temporary and the hair soon recovers. However in some cases the hair loss continues until the underlying cause is fixed.
Prescribed Drugs that
can cause hair loss
Some drugs have been reported as causing hair loss in some individuals. While not everyone will experience hair loss some drugs are more likely to cause hair loss than others.
The following is list of some drugs that have been reported to have a side effect of hair loss:
- Alloppurinol ( for the treatment of Gout)
- Heparin ( blood thinner)
- Coumarin (blood thinner)
- Clofibrate (Cholesterol lowering drug)
- Gemfibrozil (Cholesterol lowering drug)
The above drugs are only a few of the drugs that have been reported as contributing towards hair loss. If you suspect that prescription drugs that you are taking are causing hair loss you should discuss this with your doctor.
Hair loss caused by severe emotional stress
Some people experience Telogen Effluvium or sudden diffuse hair loss after a traumatic event such as the death of a family member or someone close, an accident, abuse or any other severely traumatic event.
The above types to sudden hair loss are usually temporary an in most cases hair will grow back normally soon after it has fallen out. However in some cases where diffuse and sudden hair loss occurs the hair loss may continue until the underlying cause is treated. Types of sudden diffuse hair loss that continues until the cause is treated are as follows:
- Thyroid Gland Malfunction
Hair loss that is cause by the above underlying causes will usually continue until the underlying cause is treated.
Generally the first test a doctor or specialist is likely to carry out on a patient who is experiencing hair loss is a thyroid function test, as a thyroid problem may result in hair loss, Two types of thyroid problems can occur and either of these problems can result in hair loss. These conditions are Hypothyroidism and Hyperthyroidism
--- Underproduction of Thyroxin
Hypothyroidism occurs when the thyroid gland produces too little thyroid hormone (thyroxin) to meet the bodies needs.
--- Overproduction of Thyroxin
Hyperthyroidism – Overproduction of Thyroxin Hyperthyroidism occurs when the thyroid gland produces too much Thyroxin hormone to meet the bodies needs. People with other auto-immune disease are especially vulnerable to hyperthyroidism. Hair loss may occur from either hypothyroidism or hyper thyroidism. In some cases hair loss is minimal, however some individuals experience severe hair loss. Fortunately hair loss is usually reversible with proper treatment. If you suspect that you have a problem with your thyroid function then you should visit your doctor.
Diabetes occurs when the body is unable to metabolize carbohydrates correctly. Untreated diabetes can result in hair loss.
This condition is an auto-immune disease which causes inflammation of multiple organ systems. The main signs of the disease are fever skin eruptions on the face and neck area, hands and arms. About half of the people with lupus will have hair loss. Systemic Lupus Eerythematosus mainly affects women between the ages of 20 and 50. It is thought that genetic makeup plays a major role in the development of the disease.
When inflammation of the hair follicles occurs due to infection it can lead to Scarring Alopecia. It is easy to identify a case of severe Scarring Alopecia because there will be rough patches on the surface of the scalp made up of small blood vessels and connective tissue. Scarring Alopecia can have many causes some of these causes and different types of Scarring Alopecia are discussed below.
Alopecia caused by Discoid Lupus Erythematosus
Discoid Lupus Erythematosus is a diffuse connective tissue disease which can result in hair loss on the scalp. In Discoid Lupus Erythematosis lesions occur a round scaling papules 5 to 10 mm across with follicular plugging. There may or may not be scaling. Eventually the skin becomes smooth atrophic and scarred. Lupus is a photosensitive disease therefore exposure to sunlight should be minimized. Topical corticosteroid ointments such as Triamcinolone Acetonide may be helpful in the treatment of small lesions. Also anti malarial drugs such as hydroxychloroquine are useful in the management of Discoid Lupus Erythematosis.
Lichen Planus is a rather uncommon skin disease that affects about 1% of the population. Lichen Planus is a inflammatory disease that strikes primarily the skin and mucous membranes. It usually starts as an itchy patch on the front of the wrists and forearms. the sides of the legs and ankles and lower back. In rare cases, when Lichen Planus can affect the scalp and other hairy areas this is called Lichen Planopilaris. It appears on the scalp as raised reddish-purple areas that look like lichen on a rock, or as an area of Alopecia with follicle plugging which usually clears up. Steroid lotions are used to relieve itchiness, antimalarial drugs may reduce inflammation.
Pseudopelade of Brocq is a rare Scarring Alopecia which has no potential for regrowth. It usually affects middle aged people.
Aplasia Cutis 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.
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 which are easy to cover.
Other types of Hair loss
This section discusses a few different other types of hair loss that have not been discussed in other sections.
Syphilitic Alopecia is usually a manifestation or secondary syphilis. The hair loss that occurs is patchy and often described as moth eaten. Diagnosis is made by either blood test or microscopic examination and penicillin is often used to treat the condition.
Sclerodema is a disease that causes fibrosis (hardening and tightening) of the skin. The hardening is caused by excessive collagen production, which causes hardening of the skin and when it appears on the scalp interferes with the normal functioning of the hair follicles and growth of the hair. The manifestation of Scleroderma can range from mild localized Scleroderma where just a few patches may appear on the skin or it can be severe and affect the internal organs as well. This type of Scleroderma is known as Systematic Scleroderma. Sclerodema is much more common in women with the onset usually occurring between the ages of 40-60.
Tinea Capitis is another name for ringworm, which appears on the scalp. Tinea Capitis is highly contagious and may spread throughout an entire family, school or kindergarten. It can also be passed from animals to humans as well as between people. The main symptoms or signs of Tinea Capitis is scaling and redness in a round or uneven area of hair loss. This is where the Tinea is digesting the keratin of the hair. These patches of hair loss slowly expand as the Tinea spreads. The most commonly used treatment for ringworm is an anti fungal agent which is taken once a day for a period of between four and twelve weeks. Nizoral Shampoo (Ketaconazole 2%) may occasionally be prescribed in addition to oral treatment to reduce the surface.