Smith (Sm) Antibody details
What Smith (Sm) Antibody shows
Sm (Smith) antibodies are autoantibodies highly specific for lupus, meaning a positive result strongly supports a lupus diagnosis and is rarely seen in other conditions — unlike ANA, which is sensitive but not very specific. However, Sm antibodies are present in only a minority of people with lupus, so a negative result doesn't rule out the disease; they're typically tested as part of a broader lupus antibody panel, where their high specificity makes a positive result particularly meaningful diagnostically.
Tests that include Smith (Sm) Antibody
Sm (Smith) Antibodies are highly specific autoantibodies used in the diagnosis of systemic lupus erythematosus (SLE). Their presence strongly supports an SLE diagnosis, although they are found in only a subset of patients.
- Smith (Sm) Antibody An autoantibody highly specific for lupus, though present in only a portion of people with the disease.
Sm (Smith) Antibodies are highly specific autoantibodies used in the diagnosis of systemic lupus erythematosus (SLE). Their presence strongly supports an SLE diagnosis, although they are found in only a subset of patients.
- Smith (Sm) Antibody An autoantibody highly specific for lupus, though present in only a portion of people with the disease.
ANA + 11 Components is a comprehensive blood test that includes the presence of antinuclear antibodies (ANAs), which are autoantibodies targeting the cell nucleus. A positive ANA screen suggests potential autoimmune activity. 11 ANA Components tests for 11 specific autoantibodies against distinct nuclear antigens, helping to identify or differentiate particular autoimmune diseases.
- Chromatin Antibodies Autoantibodies that target chromatin (DNA-protein complexes) inside your cells. Associated with lupus and other autoimmune conditions.
- Anti-Jo-1 An autoantibody associated with certain autoimmune muscle and lung conditions, including polymyositis, dermatomyositis, and antisynthetase syndrome.
- Ribosomal P Antibody An autoantibody associated with lupus, particularly linked to neuropsychiatric symptoms in some patients.
- RNP Antibody An autoantibody associated with mixed connective tissue disease and, at times, lupus.
- Smith (Sm) Antibody An autoantibody highly specific for lupus, though present in only a portion of people with the disease.
- Centromere B Antibody Autoantibodies that target a structure inside your cells called the centromere. Strongly associated with limited scleroderma (CREST syndrome).
- Double-Stranded DNA (dsDNA) Antibody Antibodies against double-stranded DNA. Highly specific for lupus and often used to track disease activity.
- Scleroderma (Scl-70) Antibody An autoantibody strongly associated with diffuse systemic sclerosis (scleroderma), a more widespread form of the disease.
- Sjögren's Syndrome A (SS-A/Ro) Antibody An autoantibody associated with Sjögren's syndrome and lupus; also relevant in pregnancy due to a risk of neonatal heart complications.
- Sjögren's Syndrome B (SS-B/La) Antibody An autoantibody associated with Sjögren's syndrome and lupus, often found alongside SS-A antibodies.
- Sm/RNP Antibody Measures antibodies to the Sm/RNP complex, autoantibodies linked to mixed connective tissue disease and lupus, used when evaluating a positive ANA.
Sm/RNP Antibodies are autoantibodies directed against components of small nuclear ribonucleoproteins. They are primarily used in the diagnosis of systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD), helping to distinguish between overlapping autoimmune conditions.
- RNP Antibody An autoantibody associated with mixed connective tissue disease and, at times, lupus.
- Smith (Sm) Antibody An autoantibody highly specific for lupus, though present in only a portion of people with the disease.
Not sure how to read your results? We can help.
Schedule a consultation with a Hormunity specialist. We’ll walk through every marker, interpret what it means for you, and map out the next steps for your care.
Book a specialist