CALR and systemic lupus erythematosus: Studies have indicated that age of onset can affect disease progression of autoimmune diseases, such as SLE and RA.[6,7] Studies have shown that patients with elderly-onset pSS (EopSS) have lower levels of autoantibodies, such as rheumatoid factor (RF), antinuclear antibody (ANA), anti-Ro/SSA or anti-La/SSB antibodies.[8,9]