Rheumatoid Factor IgG, Qualitative (PAN IgG RAST; Deprecated)
An older qualitative test that detects IgG rheumatoid factor in a patient sample. Positive results can support evaluation for rheumatoid arthritis but require clinical correlation.
["A positive result suggests IgG rheumatoid factor is present, but it does not by itself diagnose rheumatoid arthritis."]
Key facts at a glance
- LOINC
- 33302-1
- Short code
- Deprecated PAN IgG RAST Ql
- Synonyms
- Deprecated PAN IgG RAST Ql
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This is an older qualitative laboratory test for IgG rheumatoid factor, an antibody that can react against the body's own IgG. It is also known by the historical term PAN IgG RAST and has been deprecated, so it may not be available for new orders.
Why might I need this test?
Rheumatoid factor testing may be considered when symptoms suggest rheumatoid arthritis, such as persistent joint swelling, pain, or morning stiffness. It may also be used as part of an evaluation for other autoimmune conditions.
How is the test performed?
A patient sample is analyzed with a qualitative method to determine whether IgG rheumatoid factor is present. The laboratory may report the result as positive or negative, although current testing often uses a quantitative assay.
How do I prepare for the test?
No special preparation is usually required for this type of antibody test. Follow your clinician's or laboratory's instructions, and ask whether fasting is needed if the test is being performed with other laboratory studies.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive result means IgG rheumatoid factor was detected. This can occur with rheumatoid arthritis, but it may also be present with other autoimmune diseases, certain infections, some medications, or in some healthy people, so the result must be interpreted with symptoms and other findings. A negative result does not completely exclude rheumatoid arthritis.
Short name
IgG Rheumatoid Factor (Qualitative)
Frequently asked questions
Does a positive result mean I have rheumatoid arthritis?
What if the result is negative?
Why is this test marked as deprecated?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy