Autoimmune diseases arise from an overactive immune response of the body against substances and tissues normally present in the body. The causes of autoimmune diseases are still obscure: some are thought to be either examples of, or precipitated by, diseases of affluence. For example, arthritis and obesity are acknowledged to be related, and the World Health Organisation states that arthritis is most common in developed countries. Most autoimmune diseases are probably the result of multiple circumstances: for example, a genetic predisposition triggered by an infection.
Women tend to be affected more often by autoimmune disorders, nearly 79% of autoimmune disease patients in the USA are women  (http://www.acs.ohio-state.edu/units/research/archive/autoimmu.htm). It is not known why this is the case, although hormone levels have been shown to affect the severity of some autoimmune diseases such as multiple sclerosis  (http://www.sciencemag.org/feature/data/983519.shl).
See also : Immune system.
Below is a listing of some actual and suspected autoimmune disorders, with brief descriptions and pointers to full articles.
Disorders believed to be autoimmune diseases
- Guillain-Barré syndrome (GBS), is an acquired immune-mediated inflammatory disorder of the Lupus erythematosus is an is a chronic (long-lasting) autoimmune disease where the immune system, for unknown reasons, becomes hyperactive and attacks normal tissue. This attack results in inflammation and brings about symptoms. This is a "Non-organ specific" type autoimmune disease.
- Psoriasis is a skin disorder in which rapidly multiplying skin cells produce itchy, scaly inflamed patches on the skin.
- Hashimoto's disease is a very common form of hypothyroidism, characterised by initial inflammation of the thyroid and later dysfunction. There are several characteristic antibodies (e.g. anti-thyreoglobulin).
- Reiter's syndrome seems to be an autoimmune attack on various body systems in response to a bacterial infection and the body's confusion over the HLA_B27 marker
- Primary biliary cirrhosis appears to be an autoimmune disease that affects the biliary epithelial cells (BECs) of the small bile duct in the liver. The cause is yet to be determined but most of the patients (<90%) seem to have auto-mitochondrial antibodies (AMAs) against pyruvate dehydrogenase complex (PDC), an enzyme that is found in the mitochondria.
- Antiphospholipid antibody syndrome APS affects the blood clotting process. It causes blood clots to form in veins and/or arteries. Blood clots can occur anywhere in your body. Deep vein thrombosis,blood clots in arteries, miscarriage, heart attacks etc. may be the result of this disease.Doctor Hughes, an English Doctor, credited with discovering APS, compared the sticky blood "to an engine getting too rich a mix of gas and sputtering along." We do not know what causes APS. No cure is available yet. However, treatment is available to minimize the life threatening aspect of the illness.
- Temporal arteritis (also known as giant cell arteritis) is an inflammation of blood vessels, most commonly the large and medium arteries of the head. Untreated, the disorder can lead to significant vision loss.
- Goodpasture's syndrome is a disease characterised by rapid destruction of the kidneys and haemorrhaging of the lungs through autoimmune reaction against an antigen found in both organs.
Diseases that might be autoimmune related
- Interstitial cystitis is a urinary bladder disease characterised by pelvic pain, urinary frequency (as often as every 30 minutes), pain with sexual intercourse, but no pain with urination.
- Neuromyotonia is spontaneous muscular activity resulting from repetitive motor unit action potentials of peripheral origin. It develops as a result of both acquired or hereditary diseases. The acquired form is more frequent and is usually caused by antibodies against neuromuscular junction.
- Scleroderma is a chronic disease characterized by excessive deposits of collagen. Progressive systemic scleroderma, the serious type of the disease, can be fatal. The local type of the disease is not serious.
- Vitiligo is the spontaneous loss of pigment from areas of skin. The pigment-free areas have few or no melanocytes. Researchers have detected anti-melanocyte antibodies in some cases of vitiligo, so it seems likely that at least some instances of this condition are the result of autoimmune problems.
- Vulvodynia is used to describe pain in the vulva, often severe, of unknown cause. "Vulvar vestibulitis" is a related term.
- Autoimmune disease research (http://www.immunetolerance.org/research/autoimmune/index.html) at the Immune Tolerance Network