Lupus erythematosus Diagnosis

  • Diagnosis

    Lupus is an autoimmune disorder that can affect many different parts of the body. Normally the immune system protects the body by fighting off bacteria, viruses, and other foreign invaders. However, if you have an autoimmune disease like lupus, the immune system starts attacking your own healthy tissue. This in turn, causes inflammation, which damages the tissues. Doctors do not completely understand why autoimmunity occurs, but they suspect that it involves some combination of genetics and triggering by environmental factors, such as viruses.

    There are three major types of lupus; the most common is systemic lupus erythematosus (SLE).

    • Systemic lupus erythematosus (SLE). Systemic lupus erythematosus (SLE) is the type of lupus with which most people are familiar. It is a systemic disorder, meaning that it can attack different parts of the body, including the joints (90%), skin (50%), kidney (50%), and nervous system (25%).
    • Discoid lupus erythematosus. Lupus that is limited to the skin is called discoid lupus erythematosus. About 5% to 10% of people with discoid lupus later develop SLE.
    • Drug-induced lupus. Drug-induced lupus is triggered by taking a medication. It usually goes away a few weeks or months after the patient stops taking the drug. Drug-induced lupus usually does not cause kidney or central nervous system problems like the other forms of lupus do.

    Nine times more women than men have lupus. While the disease usually strikes women during their childbearing years, men, children, and older adults also can develop lupus. As many as two million people in the US may have lupus, according to the Lupus Foundation of America.

    Systemic lupus erythematosis (SLE) is a chronic disorder punctuated by flares and remissions. The symptoms of lupus, such as fevers, swollen joints, and fatigue, can vary from day to day. Flares (exacerbations) are unpredictable in their character, frequency, and severity. Also, each person’s illness has its own personality and pattern of flares and characteristics. These flares alternate with periods of few or no symptoms (remissions). Some patients may be free of symptoms for a long period of time, even years. About 20% of patients may experience a remission, during which they do not require treatment. It is difficult to predict what course the disease will take, as manifestations range from mild to severe. If you suffer from lupus, you may experience reactions to light (photosensitivity), hair loss, or more severe troubles, such as problems with your kidney and heart.

    There is no cure for lupus, but with good medical care, most patients can live a long time. Drugs and lifestyle changes, such as avoidance of the sun, quitting smoking, abstaining from alcohol, and maintaining a balanced diet, help patients control the disease. The 10-year survival rate is 90%. Kidney problems related to lupus pose one of the greatest risks to health, and should be managed by a specialist.

    The cause of SLE is unknown. It is believed that several factors contribute to the appearance of lupus.

    • As autoimmune diseases tend to run in families, a genetic component most likely exists; however, experts believe that many more genes are involved.
    • The disease can be triggered by infections, stress, sunlight, or ultraviolet light.
    • Sex hormones may contribute.
    • Flares are sometimes associated with pregnancy, reproductive cycles, birth control pills, and hormone replacement therapy.
    • Different elements may trigger the disease in different people.

    Certain medications cause drug-induced lupus. Some drugs have been implicated in causing drug-induced lupus, such as:

    • Procainamide (Procan, Procanbid, Promine, Pronestyl) and Quinidine (Quinaglute, Cardioquin, Cin-Quin), used to control irregular heartbeats
    • Hydralazine (Apresoline, Apresazide, Unapres) and Methyldopa (Aldoclor, Aldoril, Aldomet), used to treat high blood pressure
    • Chlorpromazine (Thorazine), an anti-psychotic tranquilizer
    • Isoniazid (INH, Rifater, Rimactane), used to treat tuberculosis; and
    • Phenytoin (Dilantin), given to control seizures.

    There are other drugs that may trigger lupus in addition to these.

    Not all people who take these drugs develop SLE. Actually, fewer than 10% of patients on such medications will develop SLE, and then only after prolonged treatment.

    Early lupus symptoms such as fatigue and joint pain often mimic other diseases. Lupus symptoms such as fatigue and pain are frequently vague, and can be attributed to other problems. Symptoms may come and go, and it is difficult to predict how long a flare of symptoms will last.

    A classic symptom of lupus is a “butterfly” facial rash Figure 01. Doctors in the 1800s named the disease lupus, meaning “wolf,” because they thought the hallmark facial rash looked like the bite of a wolf. The rash is red or pink, and it can be raised or flat. It generally covers both cheeks and crosses the nose. It may extend to the chin and ears. While this rash has led to the disorder's name, it only occurs in 20% of patients. Rashes may also appear on the arms, hands, chest, or other areas exposed to the sun.

    Click to enlarge: Lupus “butterfly” facial rash

    Figure 01. Lupus “butterfly” facial rash

    Almost all patients experience joint pain and arthritis-like symptoms. Lupus may cause joint problems similar to rheumatoid arthritis, which makes hands feel stiff, painful, and inflamed with redness, warmth, or swelling. An x-ray does not show much damage to your joints; however, you may still feel considerable pain.

    People with lupus often feel extremely tired. The fatigue felt by lupus patients is not the normal tiredness you might feel after physical exertion or exercise. Patients often describe it is as being “bone-tired,” like the kind you feel with a bad case of the “flu” or with mono. It is a deep exhaustion that rest may not relieve.

    Other symptoms include fever, sun sensitivity with the development of a rash or flare, hair loss, mouth or nose ulcers, chest pains caused by breathing, weight loss or gain, leg swelling, and seizures.

    Elevated blood pressure or swelling ankles may indicate associated kidney problems. Kidney inflammation, called nephritis, is seen in half of people with lupus. Nephritis may not produce symptoms, so regular blood and urine tests help monitor kidney function.

    Some patients develop seizures and other brain- and nerve-related symptoms. Lupus can cause neurological or psychiatric changes that can make you forgetful. You may complain about difficulty concentrating, a short attention span, headaches, dizziness, or vision problems, as well as depression. These problems can also be caused or worsened by medication or stress.

    People with lupus may experience seizures, or may be more susceptible to strokes. Problems with the ability to think or remember well may also occur. If the blood vessels in the eyes are inflamed (vasculitis), it can lead to blindness within a few days. Immediately report any neurologic or vision problems to the doctor. Symptoms of this condition are sudden blurriness of vision that doesn’t go away, although sometimes this condition is not accompanied by any symptoms.

    Additional symptoms occur if lupus affects other parts of the body. If inflammation occurs in the heart or lungs, you may experience chest pain or shortness of breath. If the digestive tract is affected, then nausea, vomiting, diarrhea, and abdominal pain may occur. Lupus can also cause changes in the number and type of blood cells in the bloodstream. For example, a decrease in the red blood cells causes anemia, so be alert to such symptoms as fatigue, palpitations, shortness of breath, and pale skin. Blood cell changes also make some patients at risk for blood clots, bleeding, or infections.

    A family history of autoimmune diseases is one risk factor. Autoimmune diseases tend to run in families. If you have lupus, your family members may be prone to developing lupus or another autoimmune disorder, such as rheumatoid arthritis, thyroid disease, or type 1 diabetes mellitus. While this genetic risk is real, it is small (less than 1 in 50).

    Immediate relatives (sister, brother, parent, child) of people with lupus are at greater risk than the general population.

    Lupus is more common in younger women and non-Caucasians. Women are nine times more likely than men to develop lupus. The disease typically begins during the childbearing years, between the ages of 15 and 45. Lupus occurs four times more often in African-American women than in Caucasians. It is also more common in Hispanics, Asians, and Native Americans.

    Because symptoms of lupus may also occur in other diseases, and because they may wax and wane in type and severity, an accurate and rapid diagnosis is often difficult. Fatigue, fever, and joint pain are common to many illnesses. One symptom may be present one day, but another might appear the next. Unfortunately, it may take months or years to reach a diagnosis. A more rapid diagnosis often evolves from an informed patient and her partnership with an internist or rheumatologist.

    Although no one test can confirm lupus, a number of tests can help solidify a diagnosis in the context of the characteristic symptoms and signs of SLE.

    • Antinuclear antibody (ANA) blood test. Antinuclear antibodies occur when immune cells react with elements in the nucleus of cells. A positive antinuclear antibody (ANA) blood test can aid diagnosis, since more than 95% of patients with lupus test positive for antinuclear antibodies. However, many other conditions can produce antinuclear antibodies. About 20% of all people will test positive for ANAs, yet won’t actually have lupus.
    • Anti-double stranded DNA test. This is a blood test that checks for certain antinuclear antibodies that may be produced by lupus patients. This test is quite specific for SLE.
    • Sm antibody test. This blood test checks for antibodies produced in response to a specific antigen that may be found in people with lupus.
    • VDRL, a syphilis test. Patients with lupus may test positive for syphilis when they do not actually have it.
    • Complete blood count (CBC). This test will tell if the patient is anemic, has a low white cell count, or a decreased number of platelets.
    • Blood chemistry levels. This test measures the levels of a number of chemical substances that are released from various tissues in the body. The amounts of these chemicals in the blood can reveal abnormalities in the tissues secreting them. For example, elevated amounts of a substance called creatinine may indicate kidney disease.
    • Inflammatory markers. The erythrocyte sedimentation rate (also called the ESR) and C-reactive protein both, when elevated, reflect active inflammation or infection.
    • X-rays of your joints
    • A biopsy. A sample from the skin or kidneys may confirm a lupus diagnosis.

    The American College of Rheumatology has established criteria that is used for studies, but can also aid in the diagnosis Table 01. If four or more of the 11 criteria occur, you may have lupus. However, other diseases also display many of these characteristics, so you must consult with your physician. The symptoms and abnormal lab tests may not occur together in time.

    Table 1.  Criteria Used to Diagnosis Lupus

    If four of the following criteria have occurred, you may have lupus
    Malar rash rash or redness on cheekbones that crosses the bridge of the nose
    Discoid rash rash raised in disc-like shapes on the arms or chest; hair may not grow in the affected areas
    Photosensitivity rash that appears after exposure to the sun
    Oral ulcers painless ulcers on the roof of the mouth
    Nonerosive arthritis pain and swelling in the joints which, under x-ray, do not reveal damage
    Pleuritis or pericarditis swelling of the membranes that surround the lungs and heart and cause chest pain when breathing
    Renal disorder slow decline of kidney function that may require dialysis
    Neurologic disorder seizures or psychosis not due to drugs or pre-existing derangement
    Hematalogic disorder reduced number of red blood cells; reduced number of white blood cells; decreased clotting ability
    Immunologic disorder false positive test for syphillis
    Positive anti-nuclear antibody test not drug-induced
    Presence of anti-dsDNA or Sm antibodies

    Tests will also be ordered to evaluate kidney function. Lupus-associated kidney problems are a common cause of major illness in lupus patients. Protein, blood, pus in the urine, ankle swelling, and high blood pressure may be signs that the kidneys are functioning poorly. A biopsy of kidney tissue may be ordered to help characterize the type and severity of the damage.

    There is no way to prevent lupus or to test people without symptoms. If anyone in your family has lupus, try to avoid known triggers, although in some cases, it may be difficult. According to the Lupus Foundation of America, possible triggers are exposure to the sun, a bad cold, ultraviolet light, sulfa drugs, penicillin, extreme stress, and pregnancy.

  • Prevention and Screening

    There is no way to prevent lupus or to test people without symptoms. If anyone in your family has lupus, try to avoid known triggers, although in some cases, it may be difficult. According to the Lupus Foundation of America, possible triggers are exposure to the sun, a bad cold, ultraviolet light, sulfa drugs, penicillin, extreme stress, and pregnancy.

Recommended Reading

Meet the Pharmacists

I'm Shereen A. Gharbia, PharmD. Welcome to PDR Health!

Check out my latest blog post on antidepressants

Lupus erythematosus Related Drugs

Lupus erythematosus Related Conditions