What is lupus?

Lupus is an inflammatory disease that can involve many parts of the body, including the joints, skin, kidneys, blood vessels, heart, lungs and brain. Most types of lupus are chronic and last the rest of a person's life. It is an autoimmune disorder, meaning the patient's immune system mistakenly attacks the body's own tissues.

How is the immune system involved?

The immune system helps protect your body by making antibodies, which are cells that attack foreign substances such as viruses and bacteria. Sometimes, however, this system malfunctions and creates abnormal autoantibodies that attack the body's healthy tissues. This causes inflammation, vasculitis (damage to blood vessels) and organ damage due to a buildup of immune system cells.

What are the types of lupus?

The most common, and generally the most serious, is called systemic lupus erythematosus (SLE). It generally involves multiple systems in a person's body.

Drug-induced lupus, brought on by certain medications, often ends when the person stops taking that drug.

Other forms of lupus include discoid lupus erythematosus, which mainly affects the skin; subacute cutaneous lupus erythematosus, which causes sores on skin exposed to the sun; and neonatal lupus, a rare disease that affects newborns.

What causes lupus?

Certain medications are linked to drug-induced lupus, but the cause of most cases of lupus is unknown. Heredity and the influence of hormones may predispose a person to lupus. The disease may be set off by environmental triggers such as viruses, bacteria, stress or exposure to light.