What is lupus?
Lupus is a chronic, autoimmune disease that can damage any part of the body (skin, joints, and/or organs inside the body). Chronic means that the signs and symptoms tend to last longer than six weeks and often for many years.
In lupus, something goes wrong with your immune system, which is the part of the body that fights off viruses, bacteria, and germs (“foreign invaders,” like the flu). Normally our immune system produces proteins called antibodies that protect the body from these invaders. Autoimmune means your immune system cannot tell the difference between these foreign invaders and your body’s healthy tissues (“auto” means “self”) and creates autoantibodies that attack and destroy healthy tissue. These autoantibodies cause inflammation, pain, and damage in various parts of the body.
Lupus is also a disease of flares (the symptoms worsen and you feel ill) and remissions (the symptoms improve and you feel better).
These are some additional facts about lupus that you should know:
- Lupus is not contagious, not even through sexual contact. You cannot “catch” lupus from someone or “give” lupus to someone.
- Lupus is not like or related to cancer. Cancer is a condition of malignant, abnormal tissues that grow rapidly and spread into surrounding tissues. Lupus is an autoimmune disease, as described above. However, some treatments for lupus may include immunosuppressant drugs that are also used in chemotherapy.
- Lupus is not like or related to HIV (Human Immune Deficiency Virus) or AIDS (Acquired Immune Deficiency Syndrome). In HIV or AIDS the immune system is underactive; in lupus, the immune system is overactive.
- Lupus can range from mild to life-threatening and should always be treated by a doctor. With good medical care, most people with lupus can lead a full life.
- Our research estimates that at least 1.5 million Americans have lupus. The actual number may be higher; however, there have been no large-scale studies to show the actual number of people in the U.S. living with lupus.
- More than 16,000 new cases of lupus are reported annually across the country.
- It is believed that 5 million people throughout the world have a form of lupus.
- Lupus strikes mostly women of childbearing age (15-44). However, men, children, and teenagers develop lupus, too. Most people with lupus develop the disease between the ages of 15-44.
- Women of color are two to three times more likely to develop lupus than Caucasians.
- People of all races and ethnic groups can develop lupus.
The American College of Rheumatology has designated 11 diagnostic criteria for SLE, as follows
- Serositis (pleuritis, pericarditis)
- Oral ulcers (painless)
- Arthritis (nonerosive)
- Photosensitive rash
- Blood dyscrasias
- Renal disorder
- Positive antinuclear antibody (ANA)
- Immunologic disorder
- Neurologic disorder
- Malar rash
- Discoid rash
To establish the diagnosis of SLE, at least four of these criteria must be present, either serially or simultaneously.
Laboratory features of SLE include both hematologic abnormalities and immunologic findings indicative of autoimmunity. Hematologic abnormalities that are commonly manifested include the following:
- Autoimmune hemolytic anemia
The presence of the following autoimmune antibodies indicates autoimmunity:
- Antibody to double-stranded DNA (anti-dsDNA)
- Antibody to Sm protein (anti-Sm)
- Antibody to Ro protein (anti-Ro; also referred to as anti-SSA)
- Antibody to La protein (anti-La; also referred to as anti-SSB)
- Antibody to ribonucleoprotein (anti-RNP)
- Antiphospholipid antibodies
With regard to clinical manifestations of SLE, every system in the body can be affected, including the following:
- Mucocutaneous system
- Musculoskeletal system
- Renal system
- Nervous system
- Cardiovascular system
- Pleura and lungs
- Gastrointestinal (GI) tract and liver
- Ocular system
Resources: Lupus.org and Medscape