Autoimmune Diseases – What Are They and How Are They Diagnosed?

How familiar are you with autoimmune diseases? 

Your body’s immune system naturally helps fight against harmful bacteria and other foreign substances. This natural response revolves around antibodies and specific immune cells. Autoimmune diseases occur when your body’s immune system fights against normal constituents, instead of harmful bacteria and other foreign substances. It has everything to do with your immune system failing to discern between “self” vs. “non-self” constituents.  This failure to discern may produce immune cells or antibodies (or auto-antibodies) that target the body’s own cells, tissues, and/or organs.  These attacks cause inflammation and tissue damage that result in autoimmune disorders. 

Over 80 diseases have been classified as resulting from autoimmune responses, and there is evidence to suggest that there are 40+ other diseases that may have an autoimmune basis.

According to the National Institutes of Health, nearly 24 million people in the US suffer from autoimmune disease. While the majority of these diseases are, in fact, rare, the number of people suffering from them continues to rise. These diseases affect women on a larger scale than men. In the case of Lupus, women are ten times more likely to be affected.

Medical professionals are unaware of what causes most autoimmune diseases, save for the fact that genetic predisposition seems to play its part. There are some autoimmune diseases, like rheumatic fever, where a virus or bacterial infection is what leads to the confused immune response. T-cells are antibodies and immune cells that attack good cells.  The T-cells misidentify the good cells as the microbes that are infecting the body.

There are two main types of autoimmune diseases, systemic and localized. The systemic autoimmune diseases are disorders that lead to multi-organ damage. In contrast, the localized autoimmune disorders lead to direct damage to a single organ or tissue. The lines can be blurred between the two types; however, as medical professionals point out that the damage caused by localized autoimmune disorders often indirectly impacts other organs and systems in the body.

There are also instances where certain autoimmune diseases do not cause antibodies to attack a particular organ or tissue but rather a certain type of cell. One example involves anti-phospholipid antibodies and how they attack regular platelet phospholipids. This happens inside blood vessels, and the event can lead to improper blood clot formation and thrombosis.

Autoimmune diseases aren’t always easily recognizable either, especially systemic disorders. Multiple symptoms that frequently change in severity can leave doctors searching for a diagnosis for an extended period of time. Any vague and slow to develop signs and symptoms, although present, can also serve to be misleading to medical professionals. There are a variety of symptoms that stem from the various autoimmune diseases, including joint pain, fever, and fatigue. Many people also report a feeling of generally being unwell.

Which lab tests are used to detect autoimmune disorders depends on which disease a medical professional suspects to be the culprit. Blood tests are commonly used for diagnosis because doctors need to know what autoantibodies are in attack mode. Two inflammation tests, CRP (or C-reactive protein) and ESR (or erythrocyte sedimentation rate), are also commonly used in diagnosis. Sometimes a person may have more than a single autoimmune disease.  As examples, individuals who suffer from Addison disease often are type 1 diabetics, and people with sclerosing cholangitis often suffer from ulcerative colitis.

Below is a list of several of the more well-known autoimmune diseases. You can also find out additional information from the AARDA (American Autoimmune Related Diseases Association) about these diseases and more.

  • Addison Disease
  • Antiphospholipid Syndrome
  • Autoimmune Hepatitis
  • Graves’ Disease
  • Guillain-Barre Syndrome
  • Multiple Sclerosis
  • Myasthenia Gravis
  • Pernicious Anemia
  • Primary Biliary Cirrhosis
  • Sclerosing Cholangitis (see Autoimmune-associated Liver Diseases)
  • Reactive Arthritis
  • Rheumatoid Arthritis
  • Juvenile Rheumatoid Arthritis
  • Sarcoidosis
  • Scleroderma
  • Sjögren Syndrome
  • Lupus (Systemic Lupus Erythematosus or SLE)
  • Type 1 Diabetes
  • Vasculitis