No two cases of lupus are exactly alike. Signs and symptoms may come on suddenly or develop slowly, may be mild or severe, and may be temporary or permanent. Most people with lupus have mild disease characterized by episodes — called flares — when signs and symptoms get worse for a while, then improve or even disappear completely for a time.

The signs and symptoms of lupus that you experience will depend on which body systems are affected by the disease. The most common signs and symptoms include:

• Fatigue
• Fever
• Joint pain, stiffness and swelling
• Butterfly-shaped rash on the face that covers the cheeks and bridge of the nose or rashes elsewhere on the body
• Skin lesions that appear or worsen with sun exposure (photosensitivity)
• Fingers and toes that turn white or blue when exposed to cold or during stressful periods (Raynaud's phenomenon)
• Shortness of breath
• Chest pain
• Dry eyes
• Headaches, confusion and memory loss

Lupus occurs when your immune system attacks healthy tissue in your body (autoimmune disease). It's likely that lupus results from a combination of your genetics and your environment.

It appears that people with an inherited predisposition for lupus may develop the disease when they come into contact with something in the environment that can trigger lupus. The cause of lupus in most cases, however, is unknown. Some potential triggers include:

• Sunlight. Exposure to the sun may bring on lupus skin lesions or trigger an internal response in susceptible people.
• Infections. Having an infection can initiate lupus or cause a relapse in some people.
• Medications. Lupus can be triggered by certain types of blood pressure medications, anti-seizure medications and antibiotics. People who have drug-induced lupus usually get better when they stop taking the medication. Rarely, symptoms may persist even after the drug is stopped.

Factors that may increase your risk of lupus include:

• Your sex. Lupus is more common in women.
• Age. Although lupus affects people of all ages, it's most often diagnosed between the ages of 15 and 45.
• Race. Lupus is more common in African-Americans, Hispanics and Asian-Americans.

Inflammation caused by lupus can affect many areas of your body, including your:

• Kidneys. Lupus can cause serious kidney damage, and kidney failure is one of the leading causes of death among people with lupus.
• Brain and central nervous system. If your brain is affected by lupus, you may experience headaches, dizziness, behavior changes, vision problems, and even strokes or seizures. Many people with lupus experience memory problems and may have difficulty expressing their thoughts.
• Blood and blood vessels. Lupus may lead to blood problems, including anemia and increased risk of bleeding or blood clotting. It can also cause inflammation of the blood vessels (vasculitis).
• Lungs. Having lupus increases your chances of developing an inflammation of the chest cavity lining (pleurisy), which can make breathing painful. Bleeding into lungs and pneumonia also are possible.
• Heart. Lupus can cause inflammation of your heart muscle, your arteries or heart membrane (pericarditis). The risk of cardiovascular disease and heart attacks increases greatly as well.

Other types of complications

Having lupus also increases your risk of:

• Infection. People with lupus are more vulnerable to infection because both the disease and its treatments can weaken the immune system.
• Cancer. Having lupus appears to increase your risk of cancer; however the risk is small.
• Bone tissue death (avascular necrosis). This occurs when the blood supply to a bone diminishes, often leading to tiny breaks in the bone and eventually to the bone's collapse.
• Pregnancy complications. Women with lupus have an increased risk of miscarriage. Lupus increases the risk of high blood pressure during pregnancy (preeclampsia) and preterm birth. To reduce the risk of these complications, doctors often recommend delaying pregnancy until your disease has been under control for at least six months.