You've probably seen people with hair loss located in well defined areas. They may be suffering from alopecia areata, a condition characterized by loss of hair or by round or oval areas of the scalp or other body parts.
Alopecia areata is 1% to 2% of the population. It affects both genders, all racial groups and can occur at any age, although in 60% of cases their patients are under 20 years.
Hair loss is asymptomatic, but some patients complain of itching or burning preceding the appearance of plaques. Generally, the areas in which the hair falls are very limited and scattered by the scalp (alopecia areata), but may become confluent and progress to total fall of hair and body hair (alopecia totalis). Changes in the surface of the nails occur in 10-50% of cases.
Although the diagnosis can be made by simple appearance of bald areas circumscribed in certain cases there is a need for biopsies of skin affected to eliminate causes of alopecia.
There is a simple test that helps identify cases of alopecia areata and distinguish them from other types of hair loss, is to simply pull gently a tuft of about 60 hairs situated on the banks of the naked area. The test is considered positive when at least six wires are uprooted.
In 10% to 42% of cases, there are other people in the family with the same problem. Several genes have been implicated in susceptibility to alopecia areata, they probably interact with environmental factors such as stress or the presence of microorganisms to trigger an abnormal immune response that damages the hair follicle.
20% to 30% of cases alopecia is associated with other diseases of immunological nature, thyroiditis, diabetes, lupus, vitiligo, etc.. Rhinitis and other allergic conditions are found in more than 40% of patients.
The natural history of disease is extremely variable. During life, there may be several episodes of the fall, followed by partial or complete recovery of the lost hair. There may be a drop site and growth in other, but the loss can also be irreversible.
When the hair grows back, it's usually fine white to color and consistency after achieving normal. With or without treatment, partial or complete growth is to be expected within a year, in the case of alopecia plates.
7% to 10% of patients develop chronic severe forms of alopecia. When alopecia areata settles before two years of age, 55% of children to develop later alopecia totalis.
Treatment is not mandatory as it does not prevent relapses, since the condition is benign and tends to regress spontaneously, but is usually indicated because the alopecia can cause major psychological disorders.
In adults with less than 50% involvement of the scalp, the first line of treatment is the injection of local cortisone derivatives. In patients who respond well, the growth can be noticed 4-8 weeks. Injections are repeated every 4 to 6 weeks. Where the hair loss was rapid, long lasting and the results are poor. If after six months there is no response, treatment can be stopped.
The topical application of corticosteroid creams containing an option is less efficient than injection, but rather used, especially in children, to prevent the pain that cause local injections.
Solutions of minoxidil - a substance that stimulates DNA synthesis in the hair follicle, applied twice a day - demonstrate efficacy by 20% to 45% of cases.
Local treatment with anthralin cream, a substance with antiproliferative properties, has been used with varying results.
Contact sensitizers such as DNCB and SADBE, which can cause immune reactions when placed in contact with the skin of the affected areas, are especially indicated when more than 50% of the scalp is affected. One study showed 60% response in these cases, with cosmetically acceptable results from the sixth month of treatment.
For treatment baldness or hair loss today exists modern medicines, as example Propecia (Finasteride). In this drugs directory you can find full description of Propecia drug, it side effects and precautions.