Autoimmune diseases

Autoimmune diseases arise from an overactive immune response of the body against substances and tissues normally present in the body. In other words, the body attacks its own cells. Today there are more than 40 human diseases classified as either definite or probable autoimmune diseases and they affect 5-7% of the population. Almost all autoimmune diseases appear without warning or apparent cause and most patients suffer from fatigue.

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 [1]. Also they tend to appear during or shortly after puberty. 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 [2]. Other causes may include the presence of fetal cells in the maternal bloodstream. [3]

Autoimmune diseases

Accepted

Diseases with a complete or partial autoimmune etiology:

• Crohn's disease is a form of inflammatory bowel disease characterized by chronic inflammation of the intestinal tract. Major symptoms include abdominal pain and diarrhea.
• Guillain-Barré syndrome (GBS), is an acquired immune-mediated inflammatory disorder of the peripheral nervous system (e.g. not the brain and spinal column). It is also called acute inflammatory demyelinating polyneuropathy, acute idiopathic polyradiculoneuritis, acute idiopathic polyneuritis and Landry's ascending paralysis.
• Lupus erythematosus 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.
• Multiple sclerosis is a disorder of the central nervous system (brain and spinal cord), which is characterised by decreased nerve function due to myelin loss and secondary axonal damage.
• Myasthenia gravis is a disorder of neuromuscular transmission leading to fluctuating weakness and fatigue. Weakness is caused by circulating antibodies that block acetylcholine receptors at the neuromuscular junction.
• Optic neuritis is an inflammation of the optic nerve that may cause a complete or partial loss of vision.
• Psoriasis is a skin disorder in which rapidly multiplying skin cells produce itchy, scaly inflamed patches on the skin.
• Rheumatoid arthritis is an autoimmune disorder that causes the body's immune system to attack the bone joints.
• Graves' disease is the commonest form of hyperthyroidism, and is caused by anti-thyroid antibodies that have the effect of stimulating the thyroid into overproduction of thyroid hormone.
• Hashimoto's disease is a common form of hypothyroidism, characterised by initial inflammation of the thyroid and later dysfunction and goiter. There are several characteristic antibodies (e.g. anti-thyroglobulin).
• Ord's thyroiditis is a thyroiditis similar to Hashimoto's disease, except the fact that the thyroid is reduced in size. In Europe, this form of thyroid inflammation is more common than Hashimoto's disease.
• Diabetes mellitus (type 1) is the result of an autoimmune attack on the islet cells of the pancreas.
• Aplastic anemia is often caused by an autoimmune attack on the bone marrow.
• 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
• Autoimmune hepatitis is when the liver is the target of the body's own autoimmune system.
• 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.
• Opsoclonus myoclonus syndrome (OMS) is a neurological disorder which appears to the result of an autoimmune attack on the nervous system. Symptoms include opsoclonus, myoclonus, ataxia, intention tremor, dysphasia, dysarthria, mutism, hypotonia, lethargy, irritability or malaise. About half of all OMS cases occur in association with neuroblastoma.
• 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.
• Acute disseminated encephalomyelitis (ADEM) is a form of encephalitis caused by an autoimmune reaction and typically occurring a few days or weeks after a viral infection or an immunization.
• 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.
• Wegener's granulomatosis is a form of vasculitis that affects the lungs, kidneys and other organs.
• Coeliac disease is a disease characterised by chronic inflammation of the proximal portion of the small intestine caused by exposure to certain dietary gluten proteins.
• Pemphigus is an autoimmune disorder that causes blistering and raw sores on skin and mucous membranes.

Suspected

Diseases suspected to be linked to autoimmunity are:

• 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.
• Chagas' disease in the chronic phase is beleaved to result from homology of a T. cruzi antigen to body tissue, resulting in a delayed autoimmune reaction leading to Chagasic cardiopathy (cardiomegaly), volvulus or constipation, and ultimately death.
• Sarcoidosis is a disease where granulomas can form anywhere in the body but particularly in the lungs.
• Chronic fatigue syndrome is a disorder whose primary symptom is usually intense fatigue. Though the syndrome likely has multiple causes, some maintain that autoimmune damage to the brain stem is the principal mechanism in a significant subset of cases.
• Dysautonomia is a malfunction of the autonomic nervous system, including such disorders as postural orthostatic tachycardia syndrome (POTS). Though dysautonomia appears to have multiple causes, post-viral autoimmune damage appears to be a frequent cause.

Reference

• Aaseng, Nathan; Franklin Watts Library Edition: Autoimmune Diseases ISBN 0-531-12553-x

External links

• Autoimmune disease research at the Immune Tolerance Network