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Alopecia areata

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Alopecia areata (AA) is a medical condition in which hair is lost from some or all areas of the body, usually from the scalp. Because it causes bald spots on the scalp, especially in the first stages, it is sometimes called spot baldness. In 1–2% of cases, the condition can spread to the entire scalp (Alopecia totalis) or to the entire epidermis (Alopecia universalis). Conditions resembling AA, and having a similar cause, occur also in other species.

Classification: Commonly, alopecia areata involves hair loss in one or more round spots on the scalp.

• Hair may also be lost more diffusely over the whole scalp, in which case the condition is called diffuse alopecia areata.

• Alopecia areata monolocularis describes baldness in only one spot. It may occur anywhere on the head.

• Alopecia areata multilocularis refers to multiple areas of hair loss.

• The disease may be limited only to the beard, in which case it is called Alopecia areata barbae.

• If the patient loses all the hair on the scalp, the disease is then called Alopecia totalis.

• If all body hair, including pubic hair, is lost, the diagnosis then becomes Alopecia universalis.

Alopecia areata totalis and universalis are rare.

Signs and symptoms: Typical first symptoms of alopecia areata are small bald patches. The underlying skin is unscarred and looks superficially normal. These patches can take many shapes, but are most usually round or oval. Alopecia areata most often affects the scalp and beard, but may occur on any hair-bearing part of the body. Different skin areas can exhibit hair loss and regrowth at the same time. The disease may also go into remission for a time, or permanently. Common in children.

The area of hair loss may tingle or be painful. The hair tends to fall out over a short period of time, with the loss commonly occurring more on one side of the scalp than the other. Exclamation point hairs are often present. Exclamation point hairs are hairs that become narrower along the length of the strand closer to the base, producing a characteristic "exclamation point" appearance.

In the case of healthy hair, if you were to try to pull some out, at most a few should come out, and ripped hair should not be distributed evenly across the tugged portion of the scalp. In cases of alopecia areata hair will tend to pull out more easily along the edge of the patch where the follicles are already being attacked by the body's immune system than away from the patch where they are still healthy.. Nails may have pitting or trachyonychia.

Diagnosis: Alopecia areata is usually diagnosed based on clinical features. Trichoscopy may aid differential diagnosis. In alopecia areata trichoscopy shows regularly distributed "yellow dots" (hyperkeratotic plugs), micro-exclamation mark hairs, and "black dots" (destroyed hairs in the hair follicle opening).

A biopsy is rarely needed in alopecia areata. Histologic findings include peribulbar lymphocytic infiltrate ("swarm of bees"). Occasionally, in inactive alopecia areata, no inflammatory infiltrates are found. Other helpful findings include pigment incontinence in the hair bulb and follicular stelae and a shift in the anagen-to-telogen ratio towards telogen.

Causes: Alopecia areata is not contagious. It occurs more frequently in people who have affected family members, suggesting that heredity may be a factor. Strong evidence that genes may increase risk for alopecia areata was found by studying families with two or more affected members. This study identified at least four regions in the genome that are likely to contain alopecia areata genes. In addition, it is slightly more likely to occur in people who have relatives with autoimmune diseases.

The condition is thought to be an autoimmune disorder in which the body attacks its own hair follicles and suppresses or stops hair growth. For example, T cell lymphocytes cluster around affected follicles, causing inflammation and subsequent hair loss. There are a few recorded cases of babies being born with congenital alopecia areata; however, these are not cases of autoimmune disease because an infant is born without a fully developed immune system.

There is some evidence that alopecia affects the part of the hair follicle that is associated with hair color. Hair that has turned gray may not be affected.

Treatment: If the affected region is small, it is reasonable to observe the progression of the illness as the problem often spontaneously regresses and the hair may grow back.For more information on hair loss treatment please check hair loss treatment.

The cause remains unknown. In cases where there is severe hair loss, there has been limited success treating alopecia areata with the corticosteroids clobetasol or fluocinonide, corticosteroid injections, or cream. Steroid injections are commonly used in sites where there are small areas of hair loss on the head or especially where eyebrow hair has been lost. Whether they are effective is uncertain. Some other medications used are minoxidil, elocon ointment (steroid cream) irritants (anthralin or topical coal tar), and topical immunotherapy cyclosporine, sometimes in different combinations.

Oral corticosteroids decrease the hair loss, but only for the period during which they are taken, and these drugs have serious adverse side effects. For small patches on the beard or head it is possible to suppress with topical tacrolimus ointments like Protopic. Symptoms may remain suppressed until aggravated by stress or other factors. Initial stages may be kept from increasing by applying topical corticosteroids. However, topical corticosteroids frequently fail to enter the skin deeply enough to affect the hair bulbs, which are the treatment target. And small lesions typically also regrow spontaneously.

In one small study without a control group, Diphenylcyclopropenone has shown a significant hair regrowth in 40% of patients with alopecia areata at 6 months, being sustained in two thirds of these after a 12-month-follow up-period. Whether this is significant remains doubtful: there is considerable spontaneous recovery as well. In terms of adapting to the disease rather than treating in an effort to cure, there are also many options available. Wigs are often used by those with Alopecia, particularly Alopecia Totalis, in which hair is entirely lost from the scalp. Wigs are available at many levels of development and technology, including wigs with suction mechanisms to keep them firmly attached to the scalp.

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