Systemic lupus erythematosus (lupus) is a disease of the immune system. Normally, the immune system protects the body from infection. However, in lupus, the immune system inappropriately attacks tissues in various parts of the body. This abnormal activity of the immune system leads to tissue damage and illness.
Lupus can be difficult to diagnose because its signs and symptoms often mimic those of other ailments. The most distinctive sign of lupus - a facial rash that resembles the wings of a butterfly unfolding across both cheeks - occurs in many but not all cases of lupus.
Some people are born with a tendency toward developing lupus, which may be triggered by infections, certain drugs or even sunlight. While there's no cure for lupus, treatments can help control symptoms.
What are the causes of lupus?
The cause of lupus is unknown. Finding the cause is the object of major research efforts. Factors that may contribute to the cause of lupus include viruses, environmental chemicals, and the person's genetic make-up. Female hormones are believed to play a role in the development of lupus because women are affected more commonly than men. This is especially true of women during their reproductive years, a time when hormone levels are highest.
No two cases of lupus are exactly alike. Signs and symptoms may come on suddenly or develop slowly, may be mild or severe, and may be temporary or permanent. Most people with lupus have mild disease characterized by episodes, called flares, when signs and symptoms get worse for a while, then improve or even disappear completely for a time.
The signs and symptoms of lupus that you experience will depend on which body systems are affected by the disease. The most common signs and symptoms include:
Diagnosis of lupus
- Fatigue and fever
- Joint pain, stiffness and swelling
- Butterfly-shaped rash on the face that covers the cheeks and bridge of the nose
- Skin lesions that appear or worsen with sun exposure (photosensitivity)
- Fingers and toes that turn white or blue when exposed to cold or during stressful periods (Reynaud’s phenomenon)
- Shortness of breath
- Chest pain
- Dry eyes
- Headaches, confusion and memory loss
is difficult because signs and symptoms vary considerably from person to person. Signs and symptoms of lupus may vary over time and overlap with those of many other disorders. No one test can diagnose lupus. The combination of blood and urine tests, signs and symptoms, and physical examination findings leads to the diagnosis.
Laboratory and imaging tests
- Complete blood count: This test measures the number of red blood cells, white blood cells and platelets as well as the amount of haemoglobin, a protein in red blood cells. Results may indicate you have anaemia, which commonly occurs in lupus. A low white blood cell or platelet count may occur in lupus as well.
- Erythrocyte sedimentation rate: This blood test determines the rate at which red blood cells settle to the bottom of a tube in an hour. A faster than normal rate may indicate a systemic disease, such as lupus. The sedimentation rate isn't specific for any one disease. It may be elevated if you have lupus, another inflammatory condition, cancer or an infection.
- Kidney and liver assessment: Blood tests can assess how well your kidneys and liver are functioning. Lupus can affect these organs.
- Urinalysis: An examination of a sample of your urine may show an increased protein level or red blood cells in the urine, which may occur if lupus has affected your kidneys.
- Antinuclear antibody (ANA) test: A positive test for the presence of these antibodies - produced by your immune system - indicates a stimulated immune system. While most people with lupus have a positive ANA test, most people with a positive ANA do not have lupus. If you test positive for ANA, your doctor may advise more-specific antibody testing.
- Chest X-ray: An image of your chest may reveal abnormal shadows that suggest fluid or inflammation in your lungs.
- Echocardiogram: This test uses sound waves to produce real-time images of your beating heart. It can check for problems with your valves and other portions of your heart.
The type of treatment prescribed will depend on several factors, including the person's age, type of medications he or she is taking, overall health, medical history and location and severity of disease. Determining whether your signs and symptoms should be treated and what medications to use requires a careful discussion of the benefits and risks with your doctor. As your signs and symptoms flare and subside, you and your doctor may find that you'll need to change medications or dosages. The medications most commonly used to control lupus include:
- Non-steroidal anti-inflammatory drugs (NSAIDs): Over-the-counter NSAIDs, such as naproxen sodium (Aleve) and ibuprofen (Advil, Motrin IB, others), may be used to treat pain, swelling and fever associated with lupus. Stronger NSAIDs are available by prescription. Side effects of NSAIDs include stomach bleeding, kidney problems and an increased risk of heart problems.
- Antimalarial drugs: Medications commonly used to treat malaria, such as hydroxychloroquine (Plaquenil), also can help control lupus. Side effects can include stomach upset and, very rarely, damage to the retina of the eye.
- Corticosteroids: Prednisone and other types of corticosteroids can counter the inflammation of lupus but often produce long-term side effects - including weight gain, easy bruising, thinning bones (osteoporosis), high blood pressure, diabetes and increased risk of infection. The risk of side effects increases with higher doses and longer term therapy.
- Immunosuppressant: Drugs that suppress the immune system may be helpful in serious cases of lupus. Examples include azathioprine (Imuran, Azasan), mycophenolate (CellCept), leflunomide (Arava) and methotrexate (Trexall).