Yale New Haven Hospital

Department of Laboratory Medicine
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Rheumatoid factor, fluid

Lab Section: 

Immunology

 

Lab Location: 

Main Lab

Test ID: 

LAB652

 

Methodology: 

Nephelometry

Schedule: 

Monday-Friday

Reported: 

2 days

Specimen Requirements: 

Collection: 3.0 mL Fluid
Pediatric volume: 0.5 mL.
PLEASE INDICATE FLUID TYPE
Unacceptable conditions: Grossly gelatinous fluids
Stability: Ambient: 48 hours; Refrigerated: 7 days; Frozen: 3 months

 

Notes: 

Clinical Indications: Rheumatoid factors (RF) are antibodies that are directed against the Fc fragment of IgG altered in its tertiary structure. Although the IgM class is the most common RF, IgG and IgA RFs have been reported. Over 75% of patients with rheumatoid arthritis (RA) have an IgM antibody to IgG immunoglobulin. This autoantibody (RF) is diagnostically useful although it may not be etiologically related to RA. The titer of RF correlates poorly with disease activity, but those patients with high titers tend to have more severe disease and thus a poorer prognosis than do sero-negative patients. Tests are usually positive for patients with nodules or clinical evidence of vasculitis.

Reference Interval: 

No reference range established.  

CPT Code(s): 

86431

Last Changed: 

12/09/2016 11:34:03

Last Reviewed: 

9/26/2017 3:02:13 PM