Autoinflammatory diseases are a relatively new category of conditions that differ from autoimmune diseases. Although both kinds of illnesses happen when the immune system attacks the body’s own tissues, they occur by different processes. Systemic autoinflammatory diseases are a group of disorders characterized by seemingly unprovoked inflammation. These diseases are notable for their relative lack of evidence of autoimmune reactivity such as high-titer autoantibodies.
The immune system in the body defends against infection. It has two parts: the acquired and the innate immune systems. The acquired (or adaptive) component develops over time. It produces antibodies that “remember” invaders and can fight them if they return. In autoimmune disease, antibodies and adaptive immune cells target the body’s own healthy tissues by mistake. The more primitive innate (or inborn) immune system causes the heat, redness, and swelling that we associate with acute inflammation. In autoinflammatory diseases, the innate immune system reacts uncontrollably and for unknown reasons.