Rheumatoid arthritis is a chronic inflammatory disease that causes joint pain, stiffness, swelling and decreased joint movement. The most commonly affected joints are the small joints in the hands and feet. The synovial lining of the joint may become inflamed, causing long-lasting or chronic pain, lack of balance or deformity.1

  • RA affects an estimated 1.5 million people in the United States
  • RA is the most common type of autoimmune arthritis
  • Early diagnosis and treatment can help control joint pain and swelling and lessen joint damage for most people with RA
  • Labcorp offers a variety of tests to aid in the diagnosis, management of treatment, and monitoring of disease activity

RA diagnosis

Early diagnosis is key to slowing the progression of the disease and preventing permanent joint damage, also known as radiographic progression.  A clinician will review, assess and discuss symptoms, perform a physical examination, order lab tests and may consider imaging tests, such as an X-ray or ultrasound.

Blood Tests used for RA Diagnosis

Traditional blood panels for RA diagnosis

  • Complete Blood Count (CBC) is used to check your overall health and check for abnormalities2
  • Erythrocyte sedimentation rate (ESR) (erythrocyte sedimentation rate) measures the rate red blood cells settle. Higher rates may indicate inflammation3
  • C-reactive protein (CRP) measures a protein made in response to inflammation4
  • Rheumatoid Factor (RF) measures proteins produced by your immune system that can attack healthy tissue5
  • Anti-cyclic citrullinated peptide (Anti-CCP) measures proteins made by the immune system that can attack healthy cells, which can indicate bone damage6
  • Antinuclear antibody (ANA) measures antibodies that your body makes to fight foreign substances7

Labcorp Specific RA Diagnosis Testing Panels

  • RheumAssure® contains Rheumatoid Factor (RF), Cyclic Citrullinated Peptide (CCP) Antibodies, and 14-3-3 eta protein tests
  • RAdx6 Profile combines four novel markers (14-3-3 eta, Anti-Sa, Anti-CEP-1, and Anti-CarP) with two traditional markers (Anti-CCP and RF-IgM) to enhance diagnosis in early or established RA and help predict disease severity
  • SeroNeg RAdx4 Profile and RA Profile (RF and Anti-CCP) reflex to SeroNeg RAdx4 These diagnostic and prognostic panels are designed to complement traditional RF and Anti-CCP testing. The profile consists of 14-3-3 eta, Anti-Sa, Anti-CEP-1, and Anti-CarP

Testing for RA treatment decisions

Your healthcare provider will determine the best course of treatment. Prior to prescribing treatment, a series of tests will be need in order to ensure the treatment is right for you.

  • If your provider is considering putting you on a biologic, they will run the following tests: CBC, CMP, TB, and a Hep B Screening
  • If your provider is suggesting thiopurine as a treatment plan, they will order the following tests: CBC, and TPMT Enzymes/TPMT Genetics
  • When Methotrexate is recommended, the following tests will be ordered: CBC and CMP

Monitoring disease activity with Vectra by Labcorp

Once your healthcare provider has made an RA diagnosis, it is essential to stay engaged with them and discuss treatment options. Monitoring your diseases and symptoms is key to achieving the best outcome possible.

Vectra by Labcorp is an advanced blood test that objectively measures inflammation caused by rheumatoid arthritis. Your Vectra score is personalized to you. Because people tend to have higher or lower levels of inflammation based on their age, gender, and level of body fat, each patient’s score is adjusted to account for these differences. Vectra reveals the severity of your RA, how well your current treatment is working and is the best predictor of future joint damage.

  • The scores range from 1-100, with lower scores indicating less RA inflammation and higher scores indicating more inflammation. Patients with Vectra scores in the low range are at a lower risk of future joint damage. Patients in the high and moderate categories are considered to have uncontrolled inflammation and may require treatment modification
  • Knowing your risk for joint damage can help you and your doctor assess the treatment plan that’s right for you
  • The Vectra test should be ordered as early as possible to establish a baseline score to compare with future Vectra scores. Changes in your score of 8 or more points in the moderate or high range indicates a change in your clinical response to therapy. This should result in a conversation with your provider about how to address the change
  • Vectra can be used after a change in drug therapy to measure your response to the new therapy

Using a molecular assessment, along with assessments by you and your doctor, can provide the most complete view of your RA inflammation.

Between appointments, you may experience frequent ups and downs with your rheumatoid arthritis. Tracking your RA symptoms can help you spot trends in how you feel and function. Having this information can help you and your provider see the bigger picture and know if your treatment plan is working well.8

Learn more about your Vectra score by downloading the Vectra by Labcorp patient brochure 

Take a deeper look at your Vectra test results with the Vectra post-test patient education tool 




To discuss your estimated out-of-pocket costs for the Vectra test ordered by your provider, please call us today.*


Our dedicated Labcorp rheumatology service team is waiting to assist (call center hours are 8am – 7pm ET): 

Call this number if you have insurance:

Call this number if you do not have insurance:

(855) 522-2677, options 2-3

RA treatment effectiveness

Newly developed laboratory tests help you and your healthcare provider in monitoring use and maximizing effectiveness of both disease-modifying anti-rheumatic drugs (DMARDs) and biologics.

  • DoseASSURE® Biologic TDM - If an inadequate response to a biologic is suspected, your healthcare provider may recommend DoseASSURE® Biologic TDM to understand your immune response to the drugs. Testing may be ordered at any time during therapy, though sample collection before the next infusion or injection is recommended
  • Methotrexate (MTX) Polyglutamates (PG) - About 30% of patients do not respond to MTX treatment or experience adverse effects.9 Testing for MTX PGs can help determine correct dosing to achieve desired therapeutic levels and clinical response10
  • Thiopurine Metabolites - Thiopurine-related testing may be used to assess dosing before and during treatment, as well as to identify you may be at risk for drug toxicity11
  • Vectra can be used after a change in drug therapy to measure your response to the new therapy


RA risks

Patients with RA have approximately 50% greater risk for cardiovascular disease (CVD) compared to the general population, and CVD is the leading cause of death in RA patients.12,13

30% of cardiovascular risk in patients with RA is attributed to systemic inflammation and other RA-related factors. 14

It is important to monitor and learn your risk for a cardiovascular event in the next three years with Vectra Cardiovascular (CV) Risk.

Vectra CV Risk is a validated test that measures proteins in the blood, called biomarkers, to assess your RA inflammation and predict your risk of having a major cardiovascular event (e.g., heart attack or stroke) in the next three years. Vectra CV Risk is the only multi-biomarker based CV risk predictor for RA patients.15

Vectra CV Risk provides an actionable result at point of care that highlights the role of reducing systemic inflammation associated with RA. Vectra CV can be added to your Vectra test for those who are 40 years old or older.

Ask your healthcare provider about the Vectra CV Risk assessment and learn more with the RA and cardiovascular risk sheet.


  1. Centers for Disease Control and Prevention. Rheumatoid Arthritis (RA). Accessed July 27, 2020. https://www.cdc.gov/arthritis/basics/rheumatoid-arthritis.html.

  2. National Library of Medicine. Blood count test. Medlineplus.gov. Accessed December 14, 2022. https://medlineplus.gov/bloodcounttests.html.

  3. National Library of Medicine. Erythrocyte Sedimentation Rate (ESR). Medlineplus.gov. Accessed December 14, 2022. https://medlineplus.gov/lab-tests/erythrocyte-sedimentation-rate-esr/.

  4. National Library of Medicine. C-Reactive Protein (CRP) test. Medlineplus.gov. Accessed December 14, 2022. https://medlineplus.gov/lab-tests/c-reactive-protein-crp-test/

  5.  National Library of Medicine. Rheumatoid Factor (RF) test. Medlineplus.gov. December 14, 2022. https://medlineplus.gov/lab-tests/rheumatoid-factor-rf-test/.

  6. National Library of Medicine. CCP Antibody tests Medlineplus.gov. December 14, 2022. https://medlineplus.gov/lab-tests/ccp-antibody-test/.

  7.  National Library of Medicine. ANA (Antinuclear Antibody) test. Medlineplus.gov. December 14, 2022. https://medlineplus.gov/lab-tests/ana-antinuclear-antibody-test/.

  8. Grainger R, Townsley H, White B, Langlotz T, Taylor WJ. Apps for People With Rheumatoid Arthritis to Monitor Their Disease Activity: A Review of Apps for Best Practice and Quality. JMIR Mhealth Uhealth. 2017;5(2):e7. Published 2017 Feb 21. doi:10.2196/mhealth.6956

  9. Goodman S. Measuring methotrexate polyglutamates. Clin Exp Rheumatol. 2010 Sep-Oct; 28 (5 Suppl 61): S24-S26.

  10. De Rotte MCFJ, den Boer E, de Jong PHP, et al. Methotrexate polyglutamates in erythrocytes are associated with lower disease activity in patients with rheumatoid arthritis. Ann Rheum Dis. 2013;0:1-7.

  11. Chevaux JB, Peyrin-Biroulet L, Sparrow MP. Optimizing thiopurine therapy in inflammatory bowel disease. Inflamm Bowel Dis. 2011 Jun; 17(6): 1428-1435.

  12. Aviña-Zubieta JA, Choi HK, Sadatsafavi M, Etminan M, Esdaile JM, Lacaille D. Risk of cardiovascular mortality in patients with rheumatoid arthritis: a meta-analysis of observational studies. Arthritis Rheum. 2008;59(12):1690-7.

  13. Andrews LW. What Rheumatoid Arthritis Does to Your Heart. Healthgrades. https://www.healthgrades.com/right-care/rheumatoid-arthritis/what-rheumatoid-arthritis-does-to-your-heart. Published October 3, 2019. Accessed September 24, 2020.

  14. Crowson CS, Rollefstad S, Ikdahl E, Kitas GD, van Riel P, Gabriel SE, et al. Impact of risk factors associated with cardiovascular outcomes in patients with rheumatoid arthritis. Ann Rheum Dis. 2018;77(1):48-54. 3. Crowson CS, Rollefstad S, Ikdahl E, Kitas GD, van Riel P, Gabriel SE, et al. Impact of risk factors associated with cardiovascular outcomes in patients with rheumatoid arthritis. Ann Rheum Dis. 2018;77(1):48-54.

  15. Curtis JR, Fenglong X, Crowson CS, et al. Derivation and internal validation of a multi-biomarker-based cardiovascular disease risk prediction score for rheumatoid arthritis patients. Arthritis Research & Therapy. Pending publication