Systemic lupus erythematosus (SLE), also known as lupus, is a chronic autoimmune disease caused by random or inherited mutations in various genes of the immune system. It affects the skin, joints, kidneys, brain, and almost every other organ. People suffering from SLE experience inflammation in the connective tissues that provide strength and flexibility to structures throughout the body. This causes joint pain and weakness, along with other symptoms, such as a red “butterfly rash” on the face, hair loss, extreme fatigue, fever, and weight loss. The symptoms of SLE often flare unpredictably, although symptoms generally worsen over time, resulting in life-threatening damage to major organs.