How Is Lupus Diagnosed?


Lupus is a chronic disease that can be difficult to diagnose because it causes symptoms similar to those of other diseases and conditions. People also experience lupus in many ways. While no one test can diagnose lupus, the advanced AVISE® CTD lupus test provides accurate lupus diagnostic information to help your doctors find answers.
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Diagnosing Lupus


Diagnosing lupus often begins with a visit to your primary care provider (PCP) who will evaluate your symptoms, review your medical history, perform a physical exam and order tests.1

One of the most common symptoms of lupus is joint or muscle pain.2 If you have this symptom and it doesn’t appear to be associated with a specific orthopedic problem, your PCP may refer you to a rheumatologist, who specializes in joint and muscle diseases and systemic autoimmune disorders.3 You may also want to see a rheumatologist if you have a family history of lupus.

If you receive a lupus diagnosis, you may see additional specialists, such as a cardiologist, dermatologist, nephrologist or gastroenterologist, based on the organs affected by the condition. Women diagnosed with lupus during pregnancy will likely see a perinatologist.4

Understanding Symptoms of Lupus


In autoimmune rheumatic diseases, your immune system attacks healthy tissue, which leads to inflammation that in turn causes symptoms such as joint pain and swelling.5 Connective tissue diseases and other autoimmune diseases can affect many different organs, so you may notice symptoms throughout your body.

Common lupus symptoms in women and men include6:


  • Joint pain or swelling
  • Muscle pain
  • Unexplained fever
  • Ongoing feelings of fatigue
  • Rashes
  • Chest pain when breathing deeply
  • Headaches
  • Sensitivity to sunlight or other light
  • Purple or pale fingers or toes due to cold or stress

Lupus commonly affects the skin and can cause rashes, hair loss and sores in the mouth. Its presentation depends on the type of lupus experienced. Discoid lupus causes round, disc-shaped (“discoid”) rashes or sores that often appear on the scalp or face. Acute cutaneous lupus results in a telltale butterfly-shaped rash. And a red, scaly rash can be the result of subacute cutaneous lupus.7

Testing to Diagnose Lupus


Because symptoms of lupus can mirror those of other conditions, your doctor will likely not diagnose the condition based on symptoms alone.1

Testing plays an important role in diagnosing lupus. Unfortunately, there isn’t a single test that will offer a definitive answer. Your care team will combine your reported symptoms and health history with multiple test results to determine whether you have the condition.

Common tests that help diagnose lupus include1:

Blood tests. There are a few different blood tests used to diagnose lupus. The standard is antinuclear antibody, or ANA, testing. ANA testing looks for signs that your immune system is producing autoantibodies, which attack healthy tissue instead of harmful viruses or bacteria.8 According to the Lupus Foundation of America, 97% of people with lupus have their ANA test results come back positive for autoantibodies.9 However, even people without an autoimmune disease can get positive ANA test results. The advanced AVISE CTD lupus test has patented biomarkers to provide more accurate lupus diagnostic information than other tests on the market. It’s typically recommended following a positive ANA test.

The AVISE CTD test is a blood test used to aid in the diagnosis of connective tissue diseases (CTDs), which are a group of autoimmune disorders that can affect multiple organ systems in the body. The test is designed to detect specific autoantibodies that are often present in individuals with CTDs.

The AVISE CTD test is intended to aid in the diagnosis of CTDs in individuals who have clinical symptoms of these diseases but may not have a definitive diagnosis based on other laboratory tests or physical exam findings. The test can also help distinguish between different types of CTDs, which can guide treatment decisions.

Rheumatologists may also use tests that measure CB-CAPs as a diagnostic tool for lupus and other autoimmune diseases. CB-CAPs are a type of complement-binding assay that measures the levels of complement proteins in the blood.10 Complement proteins are part of the immune system and play a role in fighting infections and other foreign substances in the body.

CB-CAPs can help diagnose lupus by detecting decreased levels of complement proteins in the blood. In lupus, the complement system is often activated, leading to decreased levels of complement proteins in the blood. This decrease in complement levels can be detected by CB-CAPs, which measures the binding of complement proteins to specific antibodies.

It is important to note that a negative CB-CAPs test does not rule out a diagnosis of lupus. Lupus is a complex disease that can present with a wide range of symptoms, and diagnosis requires a comprehensive medical evaluation by a rheumatologist.

CB-CAPs are a useful tool for rheumatologists in diagnosing and monitoring lupus and other autoimmune diseases. They provide a way to accurately assess complement levels in the blood, which can help guide treatment decisions and improve patient outcomes.

You may need other blood tests in addition to ANA and AVISE CTD testing. Lupus can lead to low blood cell counts, as well as blood-clotting issues. Your doctor may order a complete blood count, which measures blood cells, and a test that measures how quickly your blood clots.9

Urine tests. Lupus can affect your kidneys. Urine samples help determine if your kidneys are working properly.9

Biopsy. A small sample of skin or kidney tissue is removed. It is then reviewed under a microscope for signs that indicate an autoimmune disease.

Your Role in Diagnosis


If you’re experiencing lupus symptoms, a firm diagnosis helps you get the treatment you need. To help your care team, there are two things you can do.

1. Be prepared. Know as much as you can about your symptoms and when they appear. This helps your doctor take the appropriate next steps. Our lupus symptoms checklist allows you to document your symptoms and create a customized report to take to your appointment. The checklist can also help you track flares, and increases in lupus activity that can come and go.

2. Work with your provider. Lupus is a mysterious disease that requires many tests for diagnosis. Following a positive ANA test, talk to your provider about seeing a rheumatologist and ordering the AVISE CTD lupus test.

Take the next step and send your doctor information about AVISE CTD lupus testing.

Send Information
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Last reviewed by an Exagen subject expert on 08/24/2022.

Footnotes:

  1. Centers for Disease Control and Prevention. Diagnosing and Treating Lupus. CDC website. Reviewed June 27, 2022. https://www.cdc.gov/lupus/basics/diagnosing.htm. Accessed July 18, 2022.
  2. U.S. Department of Health & Human Services. Lupus Symptoms. Office on Women’s Health website. Updated February 18, 2021. https://www.womenshealth.gov/lupus/lupus-symptoms. Accessed July 18, 2022.
  3. American College of Rheumatology. What Is a Rheumatologist? American College of Rheumatology website. Reviewed May 2021. https://www.rheumatology.org/i-am-a/patient-caregiver/health-care-team/what-is-a-rheumatologist. Accessed July 18, 2022.
  4. Lupus Foundation of America. Doctors Who Treat Lupus. Lupus Foundation of America website. Reviewed N/A. https://www.lupus.org/resources/doctors-who-treat-lupus. Accessed July 18, 2022.
  5. U.S. National Library of Medicine. Autoimmune Disorders. MedlinePlus website. Reviewed April 24, 2021. https://medlineplus.gov/ency/article/000816.htm. Accessed July 18, 2022.
  6. Lupus Foundation of America. Lupus Symptoms. Lupus Foundation of America website. Reviewed March 10, 2017. https://www.lupus.org/resources/common-symptoms-of-lupus. Accessed July 18, 2022.
  7. Lupus Foundation of America. Lupus and the Skin. Lupus Foundation of America website. Reviewed April 16, 2021. https://www.lupus.org/resources/how-lupus-affects-the-skin. Accessed July 18, 2022.
  8. NIH National Cancer Institute. Autoantibody. National Cancer Institute website. Reviewed N/A. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/autoantibody. Accessed July 18, 2022.
  9. Lupus Foundation of America. Lab Tests for Lupus. Lupus Foundation of America website. Reviewed July 15, 2013. https://www.lupus.org/resources/lab-tests-for-lupus. Accessed July 18, 2022.
  10. Ramsey-Goldman, Rosalind; Li, Jian; Dervieux, Thierry; Alexander, Roberta Vezza (21 August 2017). "Cell-bound complement activation products in SLE"Lupus Science & Medicine.