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Test Code
U3RNP
Test Name
Anti-U3 RNP (Fibrillarin)(RDL)
CPT Codes
RUO86235
Expected Turnaround Time
14 - 21 days
Clinical Utility

The U3-RNP (Fibrillarin) particle is thought to participate in the first step of preribosomal RNA processing. Anti-U3 RNP antibodies have been shown to be highly specific for patients with SSc.
Specimen and Container Info

Specimen Type: Serum

  

Collection Container: Gold Top, Serum Separator

Alternate Collection Container: Red Top, Plain

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect specimen in gold top, serum separator tube via venipuncture.
Processing and Submission Instructions
  1. Separate serum from cells within one hour of collection.
  2. Transfer 1 mL of serum to a clear aliquot tube.
Transport Instructions

Transport to the laboratory refrigerated. 
Stability Requirements

Room Temperature

7 days

Refrigerated

14 days

Frozen

60 days

Freeze/Thaw Cycles

 Stable x1
Causes for Rejection
  • Grossly hemolyzed
  • Bacterial contamination
  • Lipemic specimen
  • Icteric specimen
  • Non-serum specimen types
Methodology
RIPA gel radiography
Reference Intervals

 See patient report.

Alternate Names
  • Anti-Fibrillarin Ab
  • Anti-U3 RNP Ab
  • U3 RNP
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Monday-Friday
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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