Smith/RNP (ENA) Antibody, IgG

0050470
copy
 

Copy Utility


emailprint
Example Reports
Negative
Positive

Ordering Recommendation

Useful in the differential diagnosis of connective tissue diseases with or without myopathy.

Mnemonic

RNP

Methodology

Semi-Quantitative Multiplex Bead Assay

Performed

Sun-Sat

Reported

1-2 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation
Collect

Serum separator tube.

Specimen Preparation

Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.2 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions

Plasma or other body fluids. Contaminated, hemolyzed, or severely lipemic specimens.

Remarks
Stability

After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)

Reference Interval

29 AU/mL or less Negative
30-40 AU/mL Equivocal
41 AU/mL or greater Positive

Interpretive Data

Smith/RNP antibodies are frequently seen in patients with mixed connective tissue disease (MCTD) and are also associated with other systemic autoimmune rheumatic diseases (SARDs) such as systemic lupus erythematosus (SLE), systemic sclerosis, and myositis. Antibodies targeting the Smith/RNP antigenic complex also recognize Smith antigens, therefore, the Smith antibody response must be considered when interpreting these results.

Compliance Category

FDA

Note

Purified Smith/RNP antigen is used in this assay. U1RNP IgG antibodies detected using immunoassays that employ recombinant U1-70K, A, and C proteins may yield discrepant results.

Hotline History

View Hotline History

 

Hotline History

Date of Change
Test Name Change
Methodology
Performance/Reported Schedule
Specimen Requirements
Reference Interval
Interpretive Data
Note
CPT Code
Component Change
Other Interface Change
New Test
Inactive
08/19/2019
X
X
X
X
N/A

CPT Codes

86235

Are you an ARUP Client? Click here for your pricing.

Components

Component Test Code* Component Chart Name LOINC
0050470 Smith/RNP (ENA) Ab, IgG 33983-8
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • Ribonucleoproteins
  • RNP
Smith/RNP (ENA) Antibody, IgG