Systemic Lupus Erythematosus
What is Systemic Lupus Erythematosus (SLE)?
Systemic Lupus Erythematosus (SLE) is the name given to a chronic multisystem inflammatory disease. It can also be known as Lupus. SLE can affect many organs, causing a wide variety of symptoms. The severity of symptoms can be mild or severe.
Inflammation is a response of the body to injury or infection. It is driven by the immune system. In SLE proteins called antibodies from the immune system become activated inappropriately and target healthy tissue, SLE is known as an autoimmune disease.
Causes of SLE
In the UK, approximately 20,000 people are estimated to be living with SLE with females being up to 12 times more likely to be affected than males. SLE is more common in individuals of African/Caribbean and Chinese origin. Most cases of SLE are diagnosed before the age of 50.
SLE is thought to result from a number of different factors. These are genetic, hormonal and environmental factors that result in the loss of the normal immune system functioning and results in the immune system targeting healthy tissues. The immune system focuses its attack on dying (or apoptotic) cells. In patients with SLE, dying cells, that are usually considered harmless, start to look dangerous. The immune system responds by making small proteins (called antibodies) that bind to the dying cells leading to them accumulating. Over time, antibodies bound to dying cells form immune complexes that activate other immune cells, leading to inflammation. The immune complexes can form in many organs.
- Inheritance of certain genes related to the immune response makes developing SLE more likely. Siblings are around 30 times more likely to develop SLE than those without an affected sibling.
- The predominance of diagnosis in women of childbearing age suggests an important role of hormones such as oestrogen in increasing the risk of developing SLE.
- Sun exposure (UV light)
- Certain medications
- Infections such as Epstein-Barr virus (EBV)
Symptoms of SLE
Patients may have a few or several of the following symptoms. They may come and go, and can be precipitated by an infection, which causes a flare of disease activity.
Symptoms can include:
- Skin rash
- a butterfly-shaped rash (malar rash) over the cheeks and bridge of the nose is commonly seen as a response to strong sun exposure (photosensitivity).
- Sometimes, the rashes can be itchy or painful. Rashes can occur on non-sun exposed areas too.
- Joint pain and stiffness- especially in small joints of the hands and feet. Patients may also notice swelling if they develop frank arthritis, but SLE doesn’t usually cause permanent damage or deformity to the joints themselves.
- General symptoms
- Weight loss
- Headaches- 1 in 3 people with SLE have migraines, and some may experience anxiety or depression
- Mouth ulcers- these may be recurrent.
- 1 in 8 people with SLE will also have secondary Sjögren’s syndrome.
- Hair loss
- Raynaud’s phenomenon– colour changes of the fingers and toes in the cold
SLE can also affect the following parts of the body:
- Lymph glands- causing swelling
- Heart and lungs- inflammation in the tissue that line the heart and lungs called pericarditis and pleurisy. These cause chest pain and shortness of breath.
- Gut, liver, pancreas or spleen- these are less frequently affected but may cause abdominal pain.
- Eyes- rarely, SLE can causes painful red eyes.
- Kidneys- 1 in 3 people with SLE may develop some form of kidney involvement that may lead to kidney damage. It can be treated successfully if it’s identified early with regular urine, blood pressure and blood tests.
- Other autoimmune diseases including those that involve the thyroid gland.
- Blood and blood vessels
- High blood pressure, especially if there is kidney involvement.
- High cholesterol levels.
- Narrowing of blood vessels, leading to an increased risk of angina, stroke or a heart attack. It is important to monitor and treat high cholesterol and high blood pressure.
- Some people with SLE may have antiphospholipid syndrome, which increases the likelihood of blood clots and miscarriage.
- SLE can affect your mood and memory.
What are the Possible Complications of SLE?
Flares of SLE can occur at any time but particularly following infection. SLE or its treatment can also increase the risk of:
- Infection- both the disease and treatments alter the immune system, leaving the body more prone to infection.
- Pregnancy complications- women with SLE have a higher risk of miscarriage, especially if they have antiphospholipid syndrome too. However, most women should be able to have a baby if they wish. It’s important that the disease is inactive when a patient conceives and any regular medications will not harm the foetus. It is important to discuss plans for a baby in advance with the GP or Rheumatologist, so that treatments can be altered if necessary.
Untreated, SLE may lead to irreversible organ damage, which may be life threatening. However, regular medication and careful monitoring can reduce the risk of this. It is important to consult your doctor if you have noticed worsening or changes in your symptoms.
How do we diagnose SLE?
The doctor will take a detailed history and examine the patient. This will be followed by blood tests and other investigations.
General Blood tests:
- Blood cell counts to look for anaemia and other low blood counts
- Kidney and liver function tests
- ESR/CRP- to look for signs of inflammation.
- Anti-Nuclear antibody test (ANA)
- Anti-dsDNA antibody test
- Anti-Ro antibody test
- Lupus anticoagulant and antiphospholipid antibody test
- Complement level test
The doctor may arrange other tests to check the function of the heart, lungs and liver:
- X-rays, ultrasound scan, CT scan, MRI scan
- urine test for any blood or protein in the urine, which may be a sign of kidney damage
At present, there is no cure for SLE, but many patients can be managed so that organ damage is prevented or minimised, especially if this treatment is initiated in the early stages of the disease.
The outlook for people with SLE has greatly improved due to modern treatments. However, its unpredictable and variable nature can make it difficult to tell how it will affect different individuals. Close monitoring is therefore needed especially during periods of flare.
The aims of treatment are to minimise symptoms, reduce inflammation and prevent organ damage. The drugs may be changed or adjusted as symptoms flare.
The following drugs may be used:
- NSAIDs e.g naproxen, ibuprofen to reduce inflammation and provide pain relief.
- Creams for skin rashes under the supervision of a dermatologist.
- Tablets- e.g. prednisolone to reduce inflammation in flare
- Joint injections
- IV drips in severe flares
- Biological therapies
- Medications to manage high blood pressure, high cholesterol
- Maintaining a healthy lifestyle reduces the risk of complecations. Use our section on advice to improve your general health.
Disease activity of SLE is monitored using symptoms and blood tests. The most common way to monitor this is using a score such as the SLE disease activity index (SLEDAI).
Versus Arthritis: http://www.versusarthritis.org
Lupus UK: http://www.lupusuk.org.uk