Evaluating patients with signs and symptoms of a connective tissue disease in whom the test for antinuclear antibodies is positive
Testing for SS-B/La antibodies is not useful in patients without demonstrable antinuclear antibodies.
For more information see Connective Tissue Disease Cascade.
Multiplex Flow Immunoassay
Anti-La
Anti-Sjogren's Syndrome
Anti-SSB (Anti-Sjogren's Syndrome B)
Autoantibodies to SS-B/LA, Serum
La (Anti-SSB)
Sjogren's Syndrome
SSB (Anti-SSB)
SSB Autoantibodies
For more information see Connective Tissue Disease Cascade.
Serum
Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Specimen Volume: 0.5 mL
0.35 mL
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | OK |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 21 days | |
Frozen | 21 days |
Evaluating patients with signs and symptoms of a connective tissue disease in whom the test for antinuclear antibodies is positive
Testing for SS-B/La antibodies is not useful in patients without demonstrable antinuclear antibodies.
For more information see Connective Tissue Disease Cascade.
SS-B/La is an extractable nuclear antigen (ENA) composed of a 48-kD protein combined with RNA species. SS-B/La antibodies are found primarily in patients with Sjogren syndrome or lupus erythematosus (LE), where they occur with frequencies of approximately 60% and 15%, respectively.(1,2) SS-B/La antibodies occur only infrequently in the absence of SS-A/Ro antibodies.
SS-B/La is 1 of 4 autoantigens commonly referred to as extractable nuclear antigens (ENA). The other ENA are SS-A/Ro, RNP, and Sm (Smith). Each ENA is composed of 1 or more proteins associated with cytoplasmic or small nuclear RNA species (snRNA) ranging in size from 80 to 350 nucleotides. Antibodies to ENA are common in patients with connective tissue diseases (systemic rheumatic diseases) including LE, mixed connective tissue disease, Sjogren syndrome, scleroderma (systemic sclerosis), and polymyositis/dermatomyositis.
For more information see Connective Tissue Disease Cascade.
<1.0 U (negative
> or =1.0 U (positive
Reference values apply to all ages.
A positive result for SS-B/La antibodies is consistent with connective tissue disease, including Sjogren syndrome and lupus erythematosus.
1. Homburger H, Larsen S: Detection of specific antibodies. In
2. Kotzin B, West S: Systemic lupus erythematosus. In Clinical
Affinity-purified SS-B antigen is coupled covalently to polystyrene microspheres, which are impregnated with fluorescent dyes to create a unique fluorescent signature. SS-B/La antibodies, if present in diluted serum, bind to the SS-B antigen on the microspheres. The microspheres are washed to remove extraneous serum proteins. Phycoerythrin (PE)-conjugated antihuman IgG antibody is then added to detect IgG anti-SS-B/La bound to the microspheres. The microspheres are washed to remove unbound conjugate, and bound conjugate is detected by laser photometry. A primary laser reveals the fluorescent signature of each microsphere to distinguish it from microspheres that are labeled with other antigens, and a secondary laser reveals the level of PE fluorescence associated with each microsphere. Results are calculated by comparing the median fluorescence response for SS-B/La microspheres to a 4-point calibration curve.(Package insert: Bioplex 2200 ANA Screen. Bio-Rad Laboratories, Hercules, CA 11/2011)
Monday through Saturday
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
86235
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
SSB | SS-B/La Ab, IgG, S | 33613-1 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
SSB | SS-B/La Ab, IgG, S | 33613-1 |