Lupus, also known as Systemic lupus erythematosus (SLE) is an autoimmune disease in which cells of the immune system attack healthy cells, tissues and organs. Inflammation caused by lupus can affect many different body systems — including joints, skin, kidneys, blood cells, brain, heart and lungs. Symptoms include muscle and joint pain, fever, rashes, chest pain, hair loss, sun or light sensitivity, kidney problems, mouth sores. Lupus diagnosis is confirmed with a positive Anti-dsDNA Antibody test.