Lupus (systemic lupus erythematosus, or SLE) is a chronic autoimmune disease in which the immune system mistakenly attacks the body’s own tissues, causing inflammation and damage to multiple organs. It can affect the skin, joints, kidneys, heart, lungs, blood cells, and brain.

Common symptoms include fatigue, joint pain, skin rashes (especially a butterfly-shaped rash across the cheeks and nose), photosensitivity, and fevers. Symptoms often flare and remit unpredictably.

Lupus is more common in women, especially those of childbearing age, and tends to be more severe in African American, Hispanic, and Asian populations. Diagnosis is based on a combination of clinical features and laboratory tests, such as ANA (antinuclear antibody), anti-dsDNA, and low complement levels.

Treatment depends on severity and organs involved, and may include NSAIDs, corticosteroids, hydroxychloroquine, or immunosuppressants like mycophenolate or biologics (e.g., belimumab).