Anti-La/SS-B antibody positivity

What it means

The presence of autoantibodies in the blood circulation that react against La/SSB autoantigens.

Anti-Ro/SSA and anti-La/SSB are considered hallmarks of Sjogrens syndrome and are associated with systemic disease, but are also present in the sera of systemic lupus erythematodes patients. The most common antinuclear antibodies in Sjogren patients are those directed against the autoantigens Ro/SSA and La/SSB. The Ro/La particle is a protein-RNA complex formed by the association of the Ro60, and La/SSB proteins with small cytoplasmic RNA (hyRNA). Anti-Ro/SSA and anti-La/SSB antibodies are detected in 50 to 70 percent of primary Sjogren patients. Anti-Ro/SSA and anti-La/SSB antibodies are correlated with younger age at diagnosis, longer disease duration, more severe dysfunction of the exocrine glands, recurrent parotid gland enlargement and higher intensity of the lymphocytic infiltrates in the minor salivary glands.

Rare diseases that can present with this3

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions, and Orphanet separately records 1 disease where this sign is specifically absent. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category