What is an autoimmune disease?

An autoimmune disease is a condition arising from an abnormal immune response to a normal body part, it releases "autoantibodies" that attacks and destroys healthy body organs, tissues or cells by mistake. Autoimmune diseases are the third most common category of disease in the United States after cancer and heart disease, they affect approximately 5%–8% of the population or 14–22 million persons. There are over 100 types of autoimmune diseases that affect human’s life.

The characteristics of autoimmune disease are as following:

1. There are high titer autoantibodies or sensitized lymphocytes can be detected in the patient blood.
2. Autoantibodies or the sensitized lymphocytes interact with target antigens in the tissues and cells, resulting pathological damage and dysfunction in the corresponding tissues and organs.
3. A similar model can be replicated in animal experiments.
4. The disease and autoimmune response intensity is closely related.
5. Most unexplained autoimmune diseases are often recurrent and chronic persistent. There is a genetic predisposition.

Common autoimmune diseases

1. Type 1 diabetes: The pancreas produces the hormone insulin, which helps regulate blood sugar levels. In type 1 diabetes, the immune system attacks and destroys insulin-producing cells in the pancreas. High blood sugar can damage blood vessels, as well as organs like the heart, kidneys, eyes, and nerves.
2. Rheumatoid arthritis (RA): In rheumatoid arthritis (RA), the immune system attacks the joints. This attack causes redness, warmth, soreness, and stiffness in the joints.
3. Psoriasis/psoriatic arthritis: Skin cells normally grow and then shed when they’re no longer needed. Psoriasis causes skin cells to multiply too quickly. The extra cells build up and form red, scaly patches called scales or plaques on the skin. About 30 percent of people with psoriasis also develop swelling, stiffness, and pain in their joints. This form of the disease is called psoriatic arthritis.
4. Multiple sclerosis: Multiple sclerosis (MS) damages the myelin sheath — the protective coating that surrounds nerve cells. Damage to the myelin sheath affects the transmission of messages between your brain and body. This damage can lead to symptoms like numbness, weakness, balance issues, and trouble walking. The disease comes in several forms, which progress at different rates. About 50 percent of people with MS need help walking within 15 years after getting the disease.
5. Systemic lupus erythematosus (lupus): Although doctors in the 1800s first described lupus as a skin disease because of the rash it produces, it actually affects many organs, including the joints, kidneys, brain, and heart. Joint pain, fatigue, and rashes are among the most common symptoms.Diagnosis

Autoimmune disease is a common multiple disease, because of its clinical symptoms of occult difficult to diagnose. And early diagnosis and treatment is very important. There are types of Autoimmune Elisa Kits for detection of autoantibodies. The antinuclear antibody test is often the first test that doctors use when symptoms suggest an autoimmune disease. A positive test means you likely have one of these diseases. Other tests look for specific autoantibodies produced in certain autoimmune diseases.