Autoimmune Diseases
Source: MedlinePlus Health Topics, U.S. National Library of Medicine
What are autoimmune diseases? Your immune system protects you from disease and infection by attacking germs that get into your body, such as viruses and bacteria. Your immune system can tell that the germs aren't part of you, so it destroys them. If you have an autoimmune disease, your immune system attacks the healthy cells of your organs and tissues by mistake. There are more than 80 types of autoimmune diseases. They can affect almost any part of your body. For example, alopecia areata is an autoimmune disease of the skin that causes hair loss. Autoimmune hepatitis affects the liver. In type 1 diabetes , the immune system attacks the pancreas. And in rheumatoid arthritis , the immune system can attack many parts of the body, including the joints, lungs, and eyes. What causes autoimmune diseases? No one is sure why autoimmune diseases happen. But you can't catch them from other people. Autoimmune diseases do tend to run in families, which means that certain genes may make some people more likely to develop a problem. Viruses, certain chemicals, and other things in the environment may trigger an autoimmune disease if you already have the genes for it. Who is at risk for autoimmune diseases? Millions of Americans of all ages have autoimmune diseases. Women develop many types of autoimmune diseases much more often than men. And if you have one autoimmune disease, you are more likely to get another. What are the symptoms of autoimmune diseases? The symptoms of an autoimmune disease depend on the part of your body that's affected. Many types of autoimmune diseases cause redness, swelling, heat, and pain, which are the signs and symptoms of inflammation. But other illnesses can cause the same symptoms. The symptoms of autoimmune diseases can come and go. During a flare-up, your symptoms may get severe for a while. Later on, you may have a remission, which means that your symptoms get better or disappear for a period of time. How are autoimmune diseases diagnosed? Doctor