Home
HelpTest Code FAU3R Anti-U3 RNP Antibodies (Fibrillarin)
Specimen Required
Collection Container/Tube: 5 mL Red
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Acceptable: SST
Collection Instructions: Draw blood in a plain red-top tube(s), serum gel tube is acceptable. Spin down and send 1 mL of serum refrigerated in a plastic vial.
Method Name
RIPA Gel Radiography
Reporting Name
Anti-U3 RNP (Fibrillarin)Specimen Type
SerumSpecimen Minimum Volume
0.3 mL (volume does NOT allow for repeat testing)
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Refrigerated (preferred) | 14 days | |
| Frozen | 60 days | ||
| Ambient | 7 days |
Reject Due To
| Gross hemolysis: | Reject |
| Thawing: | Warm OK; Cold OK |
| Gross lipemia: | Reject |
| Gross icterus | Reject |
| Other: | Anything other than serum; bacterial contamination |
Clinical Information
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. Anti-Fibrillarin (U3 RNP) antibodies are highly specific for diffuse SSc with a sensitivity of 4-10%. They are associated with isolated pulmonary arterial hypertension, myositis, renal and cardiac manifestations of SSc. 15% of IIM, mostly found in scleroderma/myositis overlap. Found in 4-10% of Diffuse SSc, <2% in Limited SSc, associated with isolated PAH, myositis, cardiac and renal involvement. More prevalent in African-Americans.
Reference Values
Negative
Performing Laboratory
Esoterix EndocrinologyTest Classification
This test was developed and its characteristics determined by LabCorp. It has not been cleared or approved by the Food and Drug Administration.CPT Code Information
86235