- Systemic lupus erythematosus (SLE) is an inflammatory auto-immune disorder that can attack a single part of the body, or the whole body (systemic).
- It develops when the immune system attacks the nuclei of the body’s cells, instead of protecting the body.
- Women are eight times more likely to be diagnosed with SLE than men are, and black and Asian women are generally more vulnerable than white women.
- SLE is difficult to diagnose, and diagnosis takes place over an extended period of time.
- SLE is incurable, but the symptoms can be treated and patients can live a fairly normal life between outbreaks of the condition.
What is systemic lupus erythematosus (SLE)?
Systemic lupus erythematosus (SLE) is a chronic, inflammatory auto-immune disorder (in which the body's defence system attacks its own tissues), which may affect one or many organs, including the skin, joints and internal organs. The following are common manifestations of SLE. One or all of these may occur, depending on the severity of the case:
Skin: about 50 percent of SLE sufferers experience a malar “butterfly” rash over the cheeks and the bridge of the nose. This rash may also appear on other parts of the body that are exposed to sun, and is made worse by sun exposure. Other kinds of skin lesions or nodules may also occur.
Musculoskeletal: characterised by joint pain, usually in the fingers, hands, knees and wrists. Bone tissue death in the bones of the shoulders and hips can also cause extreme pain.
Kidney: roughly half of people with SLE have lupus nephritis (persistent inflammation of the kidney), while most have protein deposits in some of the cells of the kidney. Those with full lupus nephritis may suffer renal failure, and require dialysis or kidney transplantation to survive.
Nervous system: up to 25 percent of SLE sufferers are affected by neurological disorders, particularly mild mental dysfunction. Any area of the brain, spinal cord, or nervous system can be negatively affected. Symptoms may include headaches, seizures, psychosis and organic brain syndrome (brain function loss).
Blood disorders: these affect up to 85 percent of patients with SLE. Arterial blood clots may form, and are associated with strokes and pulmonary embolism (blockage of an artery in the lungs). The number of platelets (particles in the blood important for the clotting process) may also decrease, or antibodies (proteins normally produced by the immune system to defend against harmful invasive substances) form that prevent blood clotting. This results in lupus anticoagulant.
Heart disorders: inflammation of the heart may occur, causing chest pain and pounding of the heart.
Lung disorders: chest pain and shortness of breath are often the result of SLE-related disorders such as pleurisy (inflammation of the lung), and pleural effusions (fluid collection between the lung and its lining).
What causes SLE?
The immune system usually controls the production and use of antibodies, which are the body’s defence against infections. However, when you have SLE or another auto-immune disease, the body’s defences are turned against itself and the antibodies attack your own blood cells, organs, tissues and so on, causing chronic (long-term) SLE disease.
The root cause or mechanism of SLE is not known – there is no proof that it is contagious, or directly related to diet or living conditions. However, there is some evidence that genetic inheritance plays a role in causing SLE.
Who gets SLE, and who is at risk?
- The incidence of SLE may be as high as one case per 2 500 people in certain populations.
- The disease most commonly develops in adult females between the ages of 15 and 40.
- There are eight to 10 cases in women for every one case in men.
- The disease is more common in black American and Asian women than in white women.
However, these statistics have their exceptions, with certain communities exhibiting high prevalence rates despite international or general tendencies. For example, there is a high prevalence of lupus in the Western Cape of South Africa amongst people of mixed ancestry (so-called “coloured” people). But for some reason lupus is rare among black people in rural areas of South Africa.
Symptoms and signs of SLE
More common symptoms of SLE may include:
- Malaise (general discomfort or ill-feeling).
- Weight loss.
- Skin rashes, such as the malar “butterfly” rash.
- Skin photosensitivity.
- Joint pain and swelling (oedema).
- Swollen glands.
- Muscle ache.
- Nausea and vomiting.
- Pleuritic chest pain – pain on breathing.
The condition will vary in activity over time, with a tendency for flaring of disease where people may develop increase in rashes, mouth ulcers, hair loss or internal organ involvement, in particular – kidney, lung and nervous system disease and joint pain. In addition, related problems, especially infections, can occur. The infections can mimic disease activity and as a result management is very difficult. In fact, treatment of SLE is an art gained by experience. Many doctors fear SLE as it is so unpredictable.
Because there are so many possible symptoms of SLE, no one test or symptom is enough to reliably diagnose the disease. Instead, your doctor will spend some time – from months to years – assessing whether symptoms, as well as the results of various tests, point to a diagnosis of SLE. Initial diagnosis usually requires that at least four of the main characteristics of SLE are present.
Tests carried out include:
- A nuclear antibody panel (ANA) test. This identifies the presence of antibodies, which are destroying the patient’s own cells by attacking the nucleus (or “command centre”) of those cells. While most people with lupus have positive ANA test results, a positive result might be caused by certain drugs, or by other infections. For this reason, other antibody tests are carried out to find out exactly which kinds of antibodies are in your system. A positive ANA test is not sufficient proof of SLE.
- Urinalysis to check for blood, protein or other unusual substances in the urine.
- Full blood count to detect a reduced lymphocyte count.
- Complement levels test, to assess how much of the blood protein complement that boosts immunity of the blood is present.
- Syphilis test – known to be falsely positive in people with lupus.
- Skin or kidney biopsy (tissue sample for analysis), if needed.
- Chest X-rays, to check for lung damage.
How is SLE treated?
Each person with SLE has a different set of symptoms, so treatment varies accordingly. In all cases, adequate rest and freedom from both physical and mental stress is essential.
In addition, the following types of medication may be administered:
- Anti-inflammatory medication to suppress swelling and arthritic pain.
- Cortisone, or corticosteroid, to combat more resistant inflammations. Cortisone is used in particular where there is organ involvement. It can be life saving in SLE.
- Anti-malarial drugs, which help to combat the inflammation, as well as rashes, light sensitivity and fatigue. They are especially useful for skin and joint disease.
- Immunosuppressive drugs, especially when the kidneys are affected. These include cyclophosphamide given as pills or infusions, and azathioprine.
- Intravenous gamma globulin, a blood protein that increases immunity and helps fight infection.
Outcome of treatment
All treatments for SLE will have some effect, but none will completely eradicate or cure the condition. Also, many treatments are toxic, with unpleasant potential side-effects. For example:
- Anti-malarials may cause stomach upsets, vomitting or a potential effect on the retina of the eye. The eye risk is very low and rheumatologists recommend a yearly eye test to check for vision changes that would not be noted by the patient. Retinal change is a dose related concern that can arise after many years of therapy rather than short-term exposure.
- Cortisone may sometimes cause increased appetite, weight gain and emotional "see-saws", and has to be tapered when stopping its use. Long-term use of cortisone can result in stretch marks on the skin, high blood pressure, extra hair growth, damaged or weak bones and arteries, high blood sugar, infections and cataracts. But with high doses, administered intravenously over a short period of time, the risks are reduced.
When to call the doctor
Consult a doctor as soon as you experience any of the symptoms of SLE, but do not assume that you have SLE. Although some commonly used treatments for lupus are available over-the-counter, SLE is a chronic and life-threatening illness, and all medication should be monitored by your GP or by a specialist.
You need to remain in close contact and communication with your doctor so that he or she can monitor the effectiveness of treatment, and adjust medication and other treatments accordingly to prevent costly and painful flare-ups of SLE.
The doctor will require to see you for regular checkups including urine analysis to check for kidney disease. Intermittent blood tests are also likely to be required to check disease activity.