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A New Free Report - What Is Lupus?
This fascinating new report from UK-based publishing house Health Research Today answers some of the most-asked questions about this baffling disease :
- What is the medical definition of lupus?
- What are the symptoms of lupus?
- What tests are there for lupus? How do you get a diagnosis?
Fill in this form and we will send you the report immediately, which you are welcome to send on to friends or family!
Tests for Lupus
This article is an extract from the ebook Freedom From Lupus!
Many of the symptoms associated with lupus are also associated with other disorders. Therefore one of the ACR criteria involves having a positive ANA test for lupus. However, doctors use a variety of other testing to also confirm a lupus diagnosis:
ENA Test
ENA stands for “Extractable Nuclear Antigens,” and they are cousin proteins to the ANA. This group of protein antibodies includes the anti-Sm, anti-Ro/SSA, anti-La/SSA, anti-RNP, anti-Scl70, anti-Jo-1, and others. The ENA test is actually a blood test panel. The test panel includes the following tests:
- SS-A and SS-B Tests: These proteins are found 60 to 80 percent of the time in Sjogren’s syndrome patients, but they can be found in lupus patients. Sometimes a positive test also confirms mixed connective tissue disease.
- RNP: The ribonucleoprotein antibody is almost always present in mixed connective tissue disease and is often present in lupus, both of which is an overlap condition. It has features that overlap with other conditions like rheumatoid arthritis, lupus, polymyositis, and scleroderma.
- Sm: The anti-Sm test is discussed in further detail below, but if it is positive it almost always confirms a lupus diagnosis.
- SCL-70: The anti-SCL-70 test is more commonly used to determine if scleroderma exists.
- Jo-1: This test is used to determine if interstitial pneumonitis (a lung inflammation), polymyositis, or dermatomyositis.
ESR Test
The ESR, or erythrocyte sedimentation rate, test is a non-specific test often used to check for general inflammation. This inflammation can be caused by a variety of conditions, but often rheumatologic illnesses like rheumatoid arthritis, lupus, polymyalgia, rheumatica, and vasculitis are to blame.
Even though rheumatologic circumstances may be the reason for ordering an ESR test, results can be elevated for a variety of non-rheumatologic reasons like infection, malignancies, and other diseases. The ESR test only suggests that inflammation is present somewhere in the body, but it does not prove it. It is also useful in diagnosing tuberculosis and tissue necrosis. There are circumstances in which the ESR test results are elevated but there is no illness in the body.
Still, the test is useful in the overall diagnosis of lupus when it is used in conjunction with other tests and ACR diagnostic criteria. It is also a quick test in that it only takes 1 hour to check the distance the red blood cells settle in unclotted blood. It is also a simple for the patient in that it only involves a quick blood draw rather than extensive testing.
C-Reactive Protein Test
The C-Reactive Protein Test, or CRP Test, measures the concentration of protein in a serum to determine if there is acute inflammation. This is a simple blood test for the patient. The CRP is detected by using an antiserum. Normally a person has less than 0.6 mg/dL of CRP in the blood.
C-reactive protein is produced by the liver during times of acute inflammation. It interacts with the immune system. Again, this is not a specific test for any particular rheumatic disease; a doctor will sometimes use the test to diagnose a flare of lupus, rheumatoid arthritis, or vasculitis. It can also be used to test for the body’s response to therapy.
However, there are times that lupus-related inflammation will not elevate levels of CRP. Therefore, a negative test does not necessarily indicate that lupus or a flare is not present. Sometimes CRP can also be elevated in heart attacks or coronary artery disease. A woman can also obtain positive CRP results during the last half of pregnancy or if she is taking oral contraceptives.
Read the rest of this article in Freedom From Lupus!
© Health Research Today
