Lupus is a chronic autoimmune disease which causes inflammation of various parts of the body, especially the skin, joints, blood and kidneys. The body's immune system normally makes proteins called antibodies to protect the body against viruses, bacteria and other foreign materials. These foreign materials are called antigens. In an autoimmune disorder such as lupus, the immune system loses its ability to tell the difference between foreign substances (antigens) and its own cells and tissues.

The immune system then makes antibodies directed against its own tissues and cells, i.e. against "self". These antibodies, called "auto-antibodies," react with the "self" antigens to form immune complexes. Immune complexes can build up in the tissues and cause inflammation and injury.

There are three types of lupus. Cutaneous lupus (also known as discoid lupus) is limited to the skin and is identified by a rash that may appear on the face, neck, or scalp. The rash may be more apparent on areas of the skin exposed to ultraviolet light (e.g. sunlight, fluorescent light). Although there are many types of lupus rash, the most common is raised, scaly and red, but not itchy.

Systemic lupus erythematosus (SLE) is usually more severe than discoid lupus. This type of lupus can cause inflammation in a number of organs. For some people this may be limited to skin and joint involvement. In others, the joints, lungs, kidneys, blood or other organs/or tissues may be affected. SLE may include periods in which few, if any, symptoms are evident ("remission") and other times in which the disease becomes active ("flare").

Certain prescribed drugs can create a lupus-like syndrome (called drug-induced lupus) which is similar to SLE. This type of lupus very rarely affects either the kidneys or the nervous system. The drugs most commonly connected with drug-induced lupus are hydralazine (used to treat hypertension) and procainamide (used to treat irregular heart rhythms). Not everyone who takes these drugs will develop drug-induced lupus. When the medications are discontinued, the symptoms of lupus usually fade.

Although the cause of lupus remains unknown, both genetic and environmental factors may play a role in its development. While an individual's genetic structure may increase the chance of developing lupus, it probably takes some kind of environmental factor to trigger the illness. Two known factors are ultraviolet rays (which can cause sunburns) and certain drugs. Infections and surgery may also trigger the symptoms of lupus.

Since lupus occurs 10-15 times more frequently in women than in men, researchers believe that hormonal factors may also influence the development of the disease.

Currently, there is no cure for lupus. However, early diagnosis and proper medical treatment can significantly help control the disease. Symptoms often vary from one individual to another and treatment is based on specific indications in each person.

The outlook for lupus patients has significantly improved over the last two decades. Better diagnostic techniques, evaluation methods and a more cautious use of medications have given physicians the tools to more effectively manage lupus symptoms and complications.

Twenty years ago only 40% of the people with lupus were expected to live more than three years following diagnosis. Today, with early diagnosis and current methods of therapy, 80-90% of people with lupus can look forward to a normal lifespan.