Relationship between autoantibodies and clinical parameters in Sjögren's syndrome.Scand J Rheumatol. 1993; 22(1):1-9.SJ
Glandular function as estimated by salivary function scintigraphy and extraglandular manifestations were compared among 174 Sjögren's syndrome (SS) patients according to their anti-Ro/SSA, anti-La/SSB, and anti-U1RNP autoantibody status, to clarify the relationship between these autoantibodies and clinical parameters in SS. These antibodies were detected by RNA-immunoprecipitation. Anti-La/SSB or only anti-Ro/SSA antibody was common in 84 primary SS (P-SS) patients, whereas the frequency of only anti-U1RNP was high in 90 secondary SS (S-SS) patients, especially in those with systemic lupus erythematosus (SLE). Antibody-negativity was common in SS with rheumatoid arthritis and was also found in 33% of P-SS. In P-SS, salivary gland dysfunction and parotid swelling were severe in patients who had serological abnormalities with anti-Ro/SSA and with or without anti-La/SSB. They were mild in antibody-negative patients who had mild extraglandular symptoms and in patients with only anti-U1RNP antibody who had Raynaud's phenomenon, pulmonary fibrosis, and later disease onset. P-SS patients positive for both anti-Ro/SSA and anti-U1RNP had SLE-like features. SS could be classified clinically according to these autoantibodies.