Ordering Recommendation

May aid in prognostication for rheumatoid arthritis. Rheumatoid Arthritis Panel (3016634) is preferred for the workup of suspected rheumatoid arthritis or undifferentiated inflammatory arthritides.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation
Collect

Serum separator tube.

Specimen Preparation

Separate serum from cells ASAP or within 2 hours of collection. Transfer 0.5 mL serum to an ARUP Standard Transport Tube. (Min: 0.3 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

Contaminated, hemolyzed, icteric, or lipemic specimens.

Remarks
Stability

After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)

Methodology

Semi-Quantitative Enzyme-Linked Immunosorbent Assay

Performed

Mon, Wed, Fri

Reported

1-4 days

Reference Interval

Test Number
Components
Reference Interval
  Rheumatoid Factor, IgG by ELISA 6 Units or less
  Rheumatoid Factor, IgM by ELISA 6 Units or less
  Rheumatoid Factor, IgA by ELISA 6 Units or less

Interpretive Data

The presence of all three rheumatoid factor (RF) isotypes at abnormal levels has high specificity for a diagnosis of rheumatoid arthritis (RA). However, the presence of RF isotypes in any combination may be found in a variety of conditions, including Sjogren syndrome and hepatitis infections.

Compliance Category

FDA

Note

Hotline History

N/A

CPT Codes

83516 x3

Components

Component Test Code* Component Chart Name LOINC
0051299 Rheumatoid Factor, IgG by ELISA 33314-6
0051300 Rheumatoid Factor, IgM by ELISA 11573-3
0051301 Rheumatoid Factor, IgA by ELISA 33313-8
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • RF Abs
  • RF IgA IgG IgM
  • RF Isotypes
  • RF3
Rheumatoid Factors, IgA, IgG, and IgM by ELISA