Although lupus has attracted more attention in recent years, it’s fairly uncommon. Based on data from lupus registries in the United States, there may be anywhere from 161,000 to 322,000 Americans living with lupus at any given time, according to the Centers for Disease Control and Prevention (CDC). More precise statistics are not available because lupus is difficult to diagnose. Additionally, lupus is not considered a reportable disease, which means medical professionals aren’t obligated to report new diagnoses to any government agencies. As a result, the CDC does not track every case of lupus diagnosed in the United States.
This guide explains how the anti-dsDNA test is used in the diagnosis and management of lupus. It also provides more information about lupus, including its signs and symptoms, the complications it can cause, and the treatment options available.
The purpose of the anti-dsDNA test is to diagnose new cases of lupus and monitor patients who have already been diagnosed with lupus. In an individual with a history of lupus, the results of an anti-dsDNA test can help determine whether the current treatment plan is working.
Experts from the Johns Hopkins Lupus Center recommend anti-dsDNA testing after receiving a positive result on an antinuclear antibody (ANA) test. The ANA test is used in the diagnosis of several autoimmune disorders, including lupus, scleroderma, Sjogren’s syndrome, and rheumatoid arthritis. It checks for antinuclear antibodies, which are antibodies that attack the nuclei of healthy cells. Although the ANA is useful for determining if someone might have an autoimmune disorder, a positive ANA result indicates that more tests are needed to determine the cause of the individual’s symptoms.
A blood sample via a venous blood draw is required for the anti-dsDNA test.
No special preparation is needed for the anti-dsDNA test.
Systemic lupus erythematosus (SLE), or lupus, is an autoimmune disease that can affect the joints, brain, kidneys, skin, and other parts of the body. Lupus can occur at any point in a person’s lifetime, but symptoms usually begin sometime between the ages of 15 and 44. Some people are more likely to develop lupus than others; for example, lupus is more common in women than it is in men. It’s also more common in Asians and African Americans. Researchers do not yet know what causes lupus, but they suspect that several factors are involved in its development. These factors include gene mutations, hormone levels, and environmental triggers. Some researchers believe that exposure to certain medications, such as penicillin and amoxicillin, can trigger lupus in someone who is already susceptible to it due to the presence of other risk factors.
Lupus causes some general symptoms, as well as symptoms specific to the part of the body affected by the disorder. General symptoms of lupus include fatigue, fever that can’t be explained by another illness, weight loss, swollen lymph nodes, mouth sores, sensitivity to sunlight, and a general feeling of illness. Every person with lupus has swelling and pain in the joints at some point. Approximately 50% of people with lupus also develop a rash on the cheeks and nose; this is called a “butterfly” rash because of the shape it makes.
SLE can affect the heart, skin, kidneys, brain, nervous system, lungs, and digestive system. When it affects the heart, it can cause the heart muscle to become inflamed or damage the heart valves. Lupus-related skin symptoms include patchy coloration and color changes when the skin is exposed to the cold. When lupus affects the kidneys, it can cause permanent kidney damage, resulting in swelling of the legs. Lupus of the nervous system causes a wide range of symptoms, including headaches, vision problems, changes in personality, and seizures. Difficulty breathing is one of the most common symptoms in people with lupus that affects the lungs. Finally, lupus can damage the digestive tract, causing nausea, vomiting, and abdominal pain.
Depending on the part of the body involved, lupus can be life-threatening. Fortunately, advances in medicine have made it possible for many people to live long lives even though they have SLE. The Lupus Foundation of America estimates that 80% to 90% of people with lupus have a normal life expectancy, provided they are monitored closely and receive appropriate treatment.
The anti-dsDNA test checks to see if an individual’s blood contains antibodies to anti-double-stranded DNA. These antibodies attack the double-stranded DNA found in the chromosomes, damaging healthy tissue. The anti-dsDNA test is also called the anti-DNA test, the antibody to dsDNA test, and the double-stranded DNA antibody test.
To check the blood for anti-dsDNA antibodies, a blood sample is required. Blood is usually collected from the cephalic vein, the basilic vein, or the larger median cubital vein, all of which are in the arm. Before inserting the needle, a phlebotomist presses gently on the skin (palpates) to make the vein more prominent, places a tourniquet about three to four inches above the insertion site, and cleanses the skin thoroughly. Once this process is complete, the phlebotomist inserts the needle into the vein and allows blood to collect in a tube made of glass or plastic. After collecting the blood, the phlebotomist removes the tourniquet and places an adhesive bandage over the insertion site to stop the bleeding. Three laboratory tests can be used to analyze the blood sample and determine if anti-dsDNA antibodies are present: radioimmunoassay, the Crithidia luciliae immunofluorescence test, or the enzyme-linked immunosorbent assay (ELISA).
Although there is no cure for lupus, several treatment options are available to relieve the symptoms and prevent further organ damage. Not everyone with lupus has the same symptoms, nor are the same organs involved in every case, so it’s critical for an individual with lupus to work with a rheumatologist to determine which treatment option is likely to produce the greatest benefit with the fewest side effects. The goal of a lupus treatment plan is to prevent flares, limit additional organ damage, and ease the symptoms of the disease.
Several types of medications are used in the treatment of lupus. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a first-line treatment aimed at reducing joint and muscle pain. NSAIDs are also useful for relieving joint swelling. Corticosteroids (“steroids”) are also used to relieve pain and swelling of the joints and muscles. People who take steroids to control their lupus symptoms typically start with a high dose and taper to a lower dose over time. This provides quick relief of lupus symptoms and helps the individual avoid the unpleasant effects that sometimes occur due to steroid withdrawal.
Some drugs control lupus flares by inhibiting the body’s immune response. For example, drugs like cyclosporine and mycophenolate mofetil suppress the immune system so that it can’t attack healthy tissue. These drugs are classified as immunosuppressants. BLyS-specific inhibitors reduce the number of abnormal B cells in the immune system. It’s these abnormal B cells that produce antibodies to healthy tissue, resulting in organ damage and other lupus symptoms. Medications used to prevent malaria — antimalarials — can also be used to treat lupus. They’re especially useful for treating fatigue, skin rashes, joint pain, and inflammation of the lungs.
If lupus damages the heart, kidneys, lungs, or brain, it may be necessary to see other medical specialists in addition to a rheumatologist. For example, a cardiologist can diagnose and treat autoimmune myocarditis, which occurs when the immune system attacks the heart muscle, causing inflammation. A nephrologist (kidney specialist) can help with complications such as lupus nephritis, a form of kidney disease that can develop in people with SLE. Lupus nephritis can cause kidney failure, making it important to seek treatment as soon as possible.
No. Although about 30% of people with SLE have elevated anti-dsDNA levels, it’s possible to have lupus without having a high anti-dsDNA level. According to the Johns Hopkins Lupus Center, a positive anti-dsDNA result is usually associated with a severe lupus flare. A person with a low level of lupus activity may have a negative anti-dsDNA result.
No. Lupus is fairly difficult to diagnose; a single test is not enough to make an accurate diagnosis. SLE is usually diagnosed based on an individual’s symptoms, the results of autoimmune tests such as the ANA and anti-dsDNA, and the development of complications associated with lupus (e.g., lupus nephritis, autoimmune myocarditis).
The American College of Rheumatology created a list of 11 criteria to be used in the diagnosis of SLE; a patient typically has to meet at least four of the criteria to qualify for a lupus diagnosis. The 11 criteria include raised patches on the skin, a butterfly rash on the face, an unusual level of sensitivity to sunlight, inflammation in at least two joints, ulcers of the mouth and nose, seizures/psychosis, inflammation of the lungs or heart muscle, blood disorders, kidney disorders, a positive ANA blood test, and a confirmed immunological disorder.
Yes. The anti-dsDNA is just one of several tests used to diagnose and monitor lupus. A rheumatologist may also order a complete blood count (CBC), a urine test to detect high protein levels in the urine, additional antibody tests, or blood tests used to determine how long it takes the blood to clot. The CBC determines the number of white blood cells, red blood cells, and platelets in the blood. In people with lupus, cell counts may be abnormal, indicating that the immune system is attacking healthy tissue.
The urine protein test can be used to determine if the immune system is attacking the kidneys, causing excess protein to spill into the urine. Other antibody tests used to diagnose lupus include the anti-Smith antibody test, the anti-U1RNP antibody test, and the anti-Ro/SSA and anti-La/SSB antibody tests. Lupus can affect the amount of time it takes for blood to clot, making clotting tests an important diagnostic tool. If the blood doesn’t clot fast enough, an individual with lupus has an increased risk of excessive bleeding after an injury; if it clots too quickly, an individual has an increased risk of stroke and other complications.
In some cases, a tissue biopsy is necessary to determine the extent of the damage caused by SLE. Biopsies of the kidneys and skin are the most common. During a biopsy, a small piece of tissue is removed and sent to a laboratory for analysis. This analysis can help determine if tissue damage is the result of lupus or something else.
It typically takes two to three days to receive the results of the anti-dsDNA test. The results may take longer if there is some kind of laboratory delay or if the ordering physician isn’t available to review the report and explain the results.
No. Although the results of some blood tests are affected by dietary intake and physical activity, the anti-dsDNA test is not. It reflects activity taking place in the immune system, which means it can’t be affected by certain foods and beverages or types of exercise.
The blood sample used for the anti-dsDNA test can be collected at a doctor’s office, walk-in clinic, hospital, or other medical facility; however, the sample must be sent to a laboratory with the specialized equipment needed to check for double-stranded DNA antibodies.
No. In some cases, an individual with a low level of anti-dsDNA antibodies may have mixed connective tissue disease, Sjogren’s syndrome, or an autoimmune disorder other than SLE.
To learn more about lupus and lupus testing, visit the following resources.
|Johns Hopkins Lupus Center||www.hopkinslupus.org/lupus-tests/lupus-blood-tests||The Johns Hopkins Lupus Center provides an overview of several antibody tests used in the diagnosis and management of lupus.|
|Office on Women’s Health||www.womenshealth.gov/lupus/lupus-diagnosis-and-treatment||The DHS Office on Women’s Health explains how lupus is diagnosed and summarizes the treatment options.|
|MedlinePlus||medlineplus.gov/ency/article/000816.htm||MedlinePlus explains what happens when the immune system cannot distinguish between harmful substances and healthy tissues.|
|Lupus Foundation of America||www.lupus.org/resources/common-symptoms-of-lupus||The Lupus Foundation of America offers a helpful video for individuals who are concerned they have lupus.|
|Centers for Disease Control and Prevention (CDC)||www.cdc.gov/lupus/facts/detailed.html||The CDC offers a comprehensive guide to lupus, including a definition and list of symptoms.|