The word “auto” is the Greek word for self. If a person has an autoimmune disease, the immune system mistakenly attacks itself, targeting the cells, tissues, and organs of a person’s own body.
There are many different autoimmune diseases, and they can each affect the body in different ways. Pemphigus vulgaris, the most common of the pemphigus diseases, affects the skin and mucous membranes. In multiple sclerosis the auotimmune reaction is directed against the brain. In Lupus, one person may have affected skin and joins whereas another may have affected skin, kidney, and lungs.
How Does the Immune System Work?
The immune system defends the body from cells seen as “foreign”. At the heart of the system is the ability to recognize and respond to substances called antigens whether they are infectious agents or part of the body itself. Most immune system cells are white blood cells.
What causes autoimmunity?
The immune system normally can distinguish “self” from “non-self.” Some lymphocytes are capable of reacting against self, resulting in an autoimmune reaction. Ordinarily these lymphocytes are suppressed. Autoimmunity occurs naturally in everyone to some degree; and in most people, it does not result in diseases. Autoimmune diseases occur when there is some interruption of the usual control process, allowing lymphocytes to avoid suppression, or when there is an alteration in some body tissue so that it is no longer recognized as “self” and is thus attacked. The exact mechanisms causing these changes are not completely understood.
How Are Autoimmune Diseases Diagnosed?
The diagnosis of an autoimmune disease is based on an individual’s sysmpoms, findings from a physical examination, and results from laboratory tests. Autoimmune disease can be difficult to diagnose, particularly early in the course of the disease. Symptoms of many autoimmune diseases – such as fatigue – are nonspecific.
Patients should be monitored closely by their doctors so environmental factors or triggers that may worsen the disease can be discussed and avoided and new medical therapy can be started as soon as possible. Frequent visits to the doctor are important in order to the physician to manage complex treatment regimens and watch for medication side effects.
Are autoimmune diseases inherited?
The genes people inherit contribute to their susceptibility for developing an autoimmune disease. Certain diseases can occur among several members of the same family. The ability to develop an autoimmune disease is determined by a dominant genetic trait that is very common (20 percent of the population). This suggests that a specific gene or set of genes predisposes a family member. The genetic predisposition alone does not cause the development of autoimmune diseases. It seems that other factors need to be present as well in order to initiate the disease process. In addition, individual family members with autoimmune diseases may inherit and share a set of abnormal genes, although they may develop diferent autoimmune diseases. For example, one first cousin may have lupus, another pemphigus, another Sjorgen’s syndrome.
Are they Contagious?
No autoimmune disease has ever been shown to be contagious or “catching.” Autoimmune diseases do not spread to other people like infections. They are not related to AIDS.