What is autoimmune disease (AD)?
Your immune system protects you by defending the body from disease and infection. When your immune system detects a threat (such as a toxin, bacteria, or virus), it mounts an immune response and produces antibodies and white blood cells to fight the invader.
When you have an autoimmune disease, however, your immune system activates in an inappropriate or abnormal manner. Unable to distinguish between self and non-self proteins, a dysfunctional immune system mistakes the body’s own cells for harmful invaders. It produces cells and antibodies that target, attack, and damage healthy cells, tissues, and organs. This results in a wide spectrum of possible symptoms and severity.
There are 80-100 known autoimmune diseases, and many more conditions are autoimmune-related or include suspected autoimmune components. Many autoimmune diseases overlap, or exhibit comorbidities and coexisting symptoms. If you have three or more autoimmune diseases, this is known as Multiple Autoimmune Syndrome (MAS).
Some autoimmune diseases are organ-specific as they affect certain areas of the body, such as the joints, gastrointestinal tract, skin, or as in type 1 diabetes, the insulin-producing cells of the pancreas. Others are systemic, meaning that immune attack occurs in different tissues of the body. Examples of systemic autoimmune diseases are Sjögren’s syndrome, systemic lupus erythematosus, scleroderma, and rheumatoid arthritis.