Sign in →

Test Code RF Rheumatoid Factor Quantitative

Additional Codes

Cerner

NextGen

Rheumatoid Factor Quantitative

Rheumatoid Factor Quantitative

RF Quant

 

Alternate Name(s)

RF

Rheumatoid Arthritis Factor

RAF

Methodology

Two-point rate

Patient Preparation

None

Collection Instructions

Standard phlebotomy practices.

Specimen Requirements

Container

Specimen Type

Tube

Lithium Heparin Plasma

PST

For up to 24 hours

 or  or 

Serum

 or 

SST

For up to 24 hours

 or  or 

 

Stability

Storage

Temperature

Stability

Room Temperature

18-28°C

≤ 1 day

If separated within 2 hours

Refrigerated

2-8°C

≤ 3 days

If separated within 2 hours

Frozen

≤-18 °C

≤ 6 months

If separated within 2 hours

Rejection Criteria

Gross Hemolysis

Result Reporting and Reference Values

Reported in IU/mL.

 

Normal Range

Critical Low

Critical High

All

<15

N/A

N/A

Reflex Testing

None

Limitations

  • Ortho reports no significant effect with the following: 
    • Bilirubin up to 60 mg/dL
    • Hemoglobin up to 1000 mg/dL
  • The following interpretive data is visible to the practitioner:
    • Pathologically high IgG (>2500 mg/dl) may interfere with quantitation of RF

Useful For

Rheumatoid factor (RF) consists of autoantibodies of immunoglobulin isotypes, IgM, IgA, IgG, and IgE.  The function of RF remains unclear, but it may play a role in the regulation of humoral and cellular immunity and protection against invading microorganisms.  Most patients with rheumatoid arthritis and Sjögren’s syndrome have elevated levels of RF. RF may also be elevated in scleroderma, dermatomyositis, Waldenström’s disease, sarcoidosis, and systemic lupus erythematosus.  There are also instances of elevated RF without apparent disease or definable clinical disorders.