Serum anti—SS‐B/La and IgA rheumatoid factor are markers of salivary gland disease activity in primary sjögren's syndrome

Abstract

Objective. To identify serologic markers of salivary gland disease activity in 43 patients with primary Sjögren's syndrome. Methods. Comparison of salivary gland biopsies (focus scores) and flow rates with serum concentrations of IgA and IgM rheumatoid factor (RF), total serum IgG, serum anti—SS‐B/La antibodies, and the erythrocyte sedimentation rate. Results. Serum anti—SS‐B/La antibody levels correlated with focus scores (r_s = 0.477, P < 0.0025). Serum IgA‐RF concentrations correlated inversely with stimulated parotid gland salivary flow rates (r_s = −0.394, P < 0.01). Conclusion. Measuring serum levels of anti—SS‐B/La and IgA‐RF would be useful when monitoring salivary responses in therapeutic trials, especially in patients with minimal salivary function.