The immune system is the body's defense against foreign substances, such as bacteria or viruses, that may be harmful. An autoimmune disease is an abnormal condition that occurs when a person's immune system attacks its own tissues as though they were foreign substances.
Why the body attacks its own cells is not known. Autoimmune diseases include lupus, rheumatoid arthritis, scleroderma, and Sjögren's syndrome. Certain types of diabetes and thyroid disease are related to autoimmune reactions. People who have autoimmune diseases are at an increased risk for infections.
To learn more about Healthwise, visit Healthwise.org.
© 1995-2020 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Donations to UW Health are managed by the University of Wisconsin Foundation, a publicly supported charitable organization under 501(c)(3) of the Internal Revenue Code.