Rheumatoid Factor (RF) IgM • Code 86431

  • Test Type
  • Specimen Information
Test Description

Used to diagnose Rheumatoid Arthritis and other associated connective tissue disorders.
Rheumatoid arthritis (RA) is a chronic inflammatory disease of unknown etiology. It typically affects the small joints in hands and feet. Unlike the wear and tear damage of osteoarthritis, rheumatoid arthritis affects the lining of the joints, causing a painful swelling that can eventually result in bone erosion and joint deformity.

When should this test be ordered?
This test is ordered when a patient is suspected to have rheumatoid arthritis. The main associated symptoms are stiffness or pain in the joints, swelling in joints or X-rays indicating cartilage or bone damage. This test is generally run along with the Anti-CCP3 antibody test in the ENA Profile-6 panel when RA is suspected.
High Risk · Outside Reference Range
(0-6569) days: >= 15 (IU/mL)
(>= 6570) days: >= 14 (IU/mL)

Calculate DAS score. If DAS >= 6, likely diagnosis of rheumatoid arthritis as per ACR guidelines. Consider analgesics such as NSAIDs and disease-modifying anti rheumatic drugs (DMARDs). Regular exercise recommended.
Borderline Risk · None
Not applicable for this test.
Low Risk · Within Reference Range
Reference Range:

(0-6569) days: <= 14 (IU/mL)
(>= 6570) days: <= 13 (IU/mL)
Testing Method Used
ELISA.

Sample is stable for 3 days at 2-8°C

Please ship samples daily.
Improvements and Prevention
Physicians may select and prescribe medications specific to your diagnosis.
Symptoms can be alleviated by maintaining a healthy weight, physical therapy or strength enhancing exercises, reduce fatigue by getting adequate rest and sleep, and consuming an anti-inflammatory diet.
Specimen Type
Serum
Fasting Required
No, but may be done with other tests that requires fasting.
Drawing and Processing
  1. Draw from a vein into a SST tubetube1
  2. Invert tube (do not shake) 1-2 times to mix adequately
  3. Let stand upright in tube rack for 30 minutes
  4. Centrifuge for 15 minutes at 3300rpm
  5. Do not leave at room temperature for more than 1 hour
  6. Keep cold in a refrigerator to maintain stability, until ready to ship
Shipping Instructions
  1. Freeze ice packs 24 hours prior to use
  2. Place ice packs inside the Styrofoam insulated kit
  3. Place processed tubes inside biohazard bag, place inside kit
  4. Seal box, print airbill and adhere to box and wait for courier to pick up
Rejection Criteria
QNS; temperature out of range upon receipt; grossly lipemic or hemolyzed; wrong specimen type; sample stability exceeded for this analyte; unlabeled or mislabeled specimen.
References

1. Hermann, E; Vogt, P; Müller, W (1986). “Rheumatoid factors of immunoglobulin classes IgA, IgG and IgM: Methods of determination and clinical value”. Schweizerische medizinische Wochenschrift

2. Banchuin, N; Janyapoon, K; Sarntivijai, S; Parivisutt, L (1992). “Re-evaluation of latex agglutination test for rheumatoid factor detection in the diagnosis of rheumatoid arthritis”.

The information provided here is intended for educational purposes only and should not be used or substituted as medical advice. You should consult a healthcare practitioner regarding medical diagnosis or treatment.