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Test Code
RFSYN
Test Name
RF by Turb,Synovial Fluid(RDL)
CPT Codes
86431
Expected Turnaround Time
7 - 14 days
Clinical Utility

The most consistent serologic finding in patients with Rheumatoid Arthritis is an increase in the concentration of RF IgM in blood and synovial fluid. RF by Turbidimetry is 95% IgM.
Specimen and Container Info

Specimen Type: Synovial Fluid

Collection Container: Sterile Non-Additive Container

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect synovial fluid aseptically in a sterile non-additive container.
Processing and Submission Instructions
  1. Transport 1 mL of synovial fluid in the original collection container.
Transport Instructions

Transport to the laboratory refrigerated.

Stability Requirements

Room Temperature

7 days

Refrigerated

14 days

Frozen

60 days

Freeze/Thaw Cycles

Stable x3
Causes for Rejection
  • Grossly hemolyzed
  • Bacterial contamination
  • Lipemic icteric
  • Non-synovial body fluids
Methodology
Quantitative Turbidimetry
Reference Intervals

See patient report.

Alternate Names
  • Rheumatoid Factor by Turbidimetry, Synovial Fluid (RDL)
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Varies
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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