Smith (ENA) Antibody, IgG
0050085
Ordering Recommendation
Secondary screening for SLE based on ANA results.
Mnemonic
SMITH
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.
Submit With Order
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 antibody is very specific for systemic lupus erythematosus (SLE) but only occurs in 30-35% of SLE cases. The presence of antibodies to Smith is often associated with renal disease.  
Note
 
CPT Code(s)
86235
Components
Component Test Code*Component Chart NameLOINC
0050085Smith (ENA) Antibody, IgG18323-6
* 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
  • Anti-Sm
  • Anti-Smith (ENA) Antibody
  • Sm antibody IgG
  • Sm/RNP