A disease in which the immune system mistakenly attacks the body’s own cells, tissues, or organs.
Normally, the immune system distinguishes the body’s own structures from foreign substances and infectious agents. In an autoimmune disease, this self-tolerance becomes disrupted, allowing immune responses to target normal body tissues.
Autoimmune diseases can affect one organ or many parts of the body. Examples include type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis.
QUICK FACT
Autoimmune disease does not mean the immune system is simply “too strong.” The problem involves an inappropriate immune response against the body’s own tissues.
COMMONLY CONFUSED WITH
Immunodeficiency: Autoimmune disease involves inappropriate immune activity against self, whereas immunodeficiency involves inadequate or impaired immune defense.
SEE ALSO