Lupus is a chronic, inflammatory autoimmune disease that can affect any part of the body. Autoimmune diseases develop when a person's immune system becomes overactive and is unable to differentiate between foreign invaders and healthy tissue. Instead of targeting only invaders like viruses and bacteria, the immune systems also attacks and destroys healthy tissue and organs. Lupus can affect many different body systems, including skin, joints, blood, kidneys, heart and lungs.
The Lupus Foundation of America estimates that at least 1.5 million people in the U.S. and 5 million people worldwide have lupus. Although lupus is found mostly in women of childbearing age, it can strike men, women and children of all ages.
The cause of lupus is unknown, however, scientists think that some people may have a genetic predisposition to lupus that can be triggered by some type of environmental contact like medication or a virus.
Types of Lupus
There are four types of lupus:
Systemic Lupus Erythematosus – This type of lupus can affect just about any part of the body, although the most common areas are the skin, joints, lungs, kidneys and blood. The effects of systemic lupus can range from mild to severe. Systemic lupus is by far the most common and also the most serious form of the disease. If someone says they have lupus, they are most likely referring to systemic lupus.
Discoid Lupus Erythematosus – This form of lupus is also called cutaneous lupus and only affects the skin. People who have discoid lupus develop a circular rash on the face, neck and scalp. They may also have sores in the mouth, nose, or vagina. Approximately 10% of people with discoid lupus will go on to develop systemic lupus. There is a good chance that these people actually had systemic lupus all along, but early on the skin rash was their main symptom.
Drug-induced Lupus Erythematosus – This type of lupus may be more accurately described as a lupus-like disease that is caused by certain prescription medications. The symptoms of drug-induced lupus are much like those of systemic lupus, although it is rare for major organs to be affected. When the offending medication is stopped, the symptoms will usually disappear within six months.
Neonatal Lupus – This is a rare form of lupus that affects newborn babies. It is caused when antibodies from the mother act upon the infant in the womb. The newborn may have a skin rash, liver problems and/or low blood cell counts. Fortunately, these symptoms usually disappear after several months. In the most serious cases, the baby can have a heart defect.
Symptoms of Lupus
Due to the fact that lupus can affect just about any part of the body, there is a wide range of possible symptoms. According to the Lupus Foundation of America, the most common symptoms of lupus are:
- Extreme fatigue (tiredness)
- Painful or swollen joints
- Anemia (low numbers of red blood cells or hemoglobin, or low total blood volume)
- Swelling (edema) in feet, legs, hands, and/or around eyes
- Pain in chest on deep breathing (pleurisy)
- Butterfly-shaped rash across cheeks and nose
- Sun- or light-sensitivity (photosensitivity)
- Hair loss
- Abnormal blood clotting
- Fingers turning white and/or blue when cold (Raynaud’s phenomenon)
- Mouth or nose ulcers
Lupus symptoms may vary from one person to another; and even in the same person, symptoms can change over time. Most people with lupus experience fluctuations in disease activity – sometimes symptoms may be severe and other times almost unnoticeable.
Diagnosing lupus can be a difficult task. In addition to symptom fluctuations, many lupus symptoms are very similar to other disorders, making it even harder to pin down what is actually causing the symptom. Another factor that can make a lupus diagnosis challenging is the fact that laboratory tests may also vary, giving a positive result one time and a negative result another time.
Ultimately, a lupus diagnosis is usually based on a combination of factors, including: