Antibodies in Sjogrens Syndrome
What other antibodies have been described in Sjogrens Syndrome?
Anti-SSA and anti-SSB may precede the diagnosis of SS by up to two decades. A subset of SS patients (5%), who may or may not have overlap with systemic sclerosis, has anti-centromere antibodies. These patients appear to be at higher risk for extraglandular disease, including Raynaud’s phenomenon and lymphoma. A panel of novel autoantibodies, including salivary protein-1, carbonic anhydrase 6, and parotid secretory protein, is being marketed as the Sjo test. Initial studies suggest that these antibodies may be helpful to identify “seronegative” patients who otherwise meet ACR/EULAR criteria as well as patients with “incomplete SS” (<4 ACR/EULAR criteria). This test requires further validation before routine use in clinical practice, however, and current criteria do not incorporate these antibodies in the classification of SS.