Sarcoidosis is a disease that is produced by abnormal actions of the immune system. No definite trigger is known, as of 2011, but scientists think that the cause of sarcoidosis may be related to the way individual people react to unknown substances in the environment. Genetics, or abnormally strong allergic reactions, may be the cause, but this is not yet proven. In addition, sarcoidosis tends to occur within families, which strongly points to genetic factors.
A healthy human immune system uses a combination of cell types and molecules to defend against infection. Sometimes the components of the immune system go haywire and actually cause disease, and this is the basis of sarcoidosis. The known physical cause of sarcoidosis problems is that the cells of the immune system stick together abnormally, and form lumps in essential organs like lungs or skin. These lumps are associated with inflammation, and over time, can damage the organs and prevent them from working properly.
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One possible cause of sarcoidosis is that the patient is experiencing an over-the-top response to an infection by a pathogen. Alternatively, the condition may be part of an allergic reaction to something in the environment. In both these cases, the immune system is to blame, as it is not reacting to an immune challenge in a proportionate manner.
As sarcoidosis tends to run in families, scientists think that genetic make-up is closely associated with the cause of sarcoidosis. Each individual person gets genes from his or her mother, and his or her father, so people who are related tend to share a high proportion of genes. In addition to running in families, sarcoidosis is most common in people whose ancestors came from the north of Europe, or people with African ancestry, which further points to a genetic factor in the development of the disease.
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Age is also an important factor in sarcoidosis, as the illness is generally first seen in people between the ages of 20 and 40. Women also suffer more from the disease than men, which may be due to the difference in genes from sex chromosomes, or to the difference in biology in general. These are the major risk factors for sarcoidosis, and no specific environmental or lifestyle factors have been noted as of 2011.
Many people with sarcoidosis see their illness improve over the span of years, and the death rate from the condition is relatively low. A typical treatment for a person with sarcoidosis involves reducing the inflammation and other problems caused by the immune overreaction with corticosteroids. Often, patients do not require medical treatment at all to get better.