SLE: Systemic Lupus Erythematosus
General Information
Systemic lupus erythematosus (SLE) is a chronic (long-term) inflammatory disease. It can affect any part of the body - including the skin, muscles, joints, internal organs, nervous system, blood and blood vessels - causing inflammation and tissue damage. Anyone can develop SLE, however it is nine times more common in women than it is in men. It can develop at any age, however it usually develops between the ages of 15 and 45 years. SLE is more prevalent in Maori, Pacific Island and Asian races than in Caucasians. SLE should not be confused with discoid lupus erythematosus. This is a similar condition to SLE, however it only affects the skin. The condition is characterised by a raised, coin-shaped red rash on the skin, which may become thickened and scaly. A small percentage of people with discoid lupus erythematosus will go on to develop SLE.Causes
SLE is described as an autoimmune disease, where the body's immune system attacks and damages the body's own healthy tissues. A healthy immune system produces proteins called antibodies to fight and destroy infectious agents such as bacteria and viruses. However in SLE the immune system produces antibodies that attack the body's own healthy tissues. These antibodies are called autoantibodies. It is not known why autoantibodies form but they cause much of the tissue damage and inflammation associated with SLE. The causes of SLE are unknown. It is thought however that a combination of factors may work together to trigger the development of the condition. Factors thought to contribute to the development of SLE include:Genetic (inherited) factors:
Although uncommon, the tendency to develop the condition may run in families giving rise to the theory that genetic factors influence its development.Infectious agents:
Some research has indicated that SLE is triggered by the abnormal response by the body’s immune system to a viral infection.Hormonal factors:
Because substantially more women than men suffer from SLE, female hormones are thought to play a role in the development of the disease. It is known that some medications, such as those used for treating epilepsy, high blood pressure and heart conditions, can lead to the development of SLE symptoms. When this occurs it is referred to as drug induced lupus. This is a rare occurrence however and symptoms disappear when the medications are stopped.Signs and Symptoms
There is great individual variation as to the nature and severity of SLE symptoms experienced. SLE can vary from a mild condition that affects only one area of the body, to a rapidly progressive disease that can affect many areas of the body at once. Fortunately it is usually a mild disease which most commonly only affects the skin, muscles and joints. Approximately only 5% of people with SLE will experience severe symptoms. SLE is characterised by periods of remission (absence of symptoms) and "flares" (when symptoms are problematic). Flares can be triggered by factors such as sunlight, increased stress and some medications. The first symptoms of SLE may be vague. There may be a feeling of being generally unwell or of having a continuous dose of the flu. Muscle and joint aches, and fever may also be present.Subsequent symptoms may include:
- Fatigue
- Weakness
- Weight loss
- Skin rashes - most commonly a characteristic rash across the nose and cheeks known as the "butterfly" or "malar" rash
- Hair loss
- Mouth ulcers
- Red sore dry eyes
