Pathogenic autoantibodies are the primary cause of tissue damage in patients with lupus. Systemic lupus erythematosus is a systemic autoimmune disease that can affect any part of the body. The immune system is a complex system within the body that is designed to fight infectious agents, such as bacteria and other foreign microbes. Lupus can be difficult to diagnose because its signs and symptoms often mimic those of other ailments.
Lupus is more common in women than men, and for reasons that are not precisely understood, its peak incidence is after puberty. Lupus is characterized by periods of illness, called flares, and periods of wellness, or remission. Symptoms of lupus vary widely depending on the individual case and the form of lupus present.