Picture of Lupus
Lupus is an autoimmune condition in which the immune system attacks certain tissues in the body. Lupus may affect the heart, lungs, skin, joints, kidneys, or nervous system. Lupus that affects just the skin is known as discoid lupus. When the internal organs are affected the condition is called systemic lupus erythematosus (SLE). Approximately 10% of people who have lupus have SLE. Lupus affects 8 times as many women as men. The exact cause of SLE is unknown but a combination of viruses, hereditary factors, ultraviolet light, and medications are believed to play a role.
There is no one test to diagnose lupus. A diagnosis is made on the basis of signs, symptoms, and a variety of test results. These include:
- Butterfly rash across the cheeks and bridge of the nose (malar rash)
- Patchy discoid skin rash that may result in scarring
- Sensitivity to sunlight (photosensitivity)
- Inflammation in the lining of the heart (pericarditis) or the lining of the lungs (pleuritis)
- Ulcers on the inside of the mouth, throat, or nose
- Arthritis and tenderness in 2 or more joints of the extremities
- Brain inflammation manifesting as either psychosis or seizures
- Low white cell count, low red cell count, low platelets, or other blood count abnormalities
- Positive antinuclear (ANA) antibody test
- Immune system disorder manifested as either a false positive blood test for syphilis or the presence of lupus anticoagulant, positive LE prep test, anti-DNA antibodies, anti-Sm antibodies, or anticardiolipin antibodies
- Presence of cellular elements or protein in the urine
Text Reference: National Institute of Arthritis and Musculoskeletal and Skin Diseases: "What Is Lupus?"