Lacrimal and salivary immunoglobulins in Sjögren's syndrome

The diagnosis of Sjögren's syndrome is sometimes difficult. We have previously demonstrated the diagnostic value of salivary immunoglobulins IgG and IgM in Sjögren's syndrome. In the present study, we assessed both lacrimal immunoglobulins (1 Ig) and salivary Ig (s Ig) in Sjögren's syndrome. We studied 112 patients: 71 had rheumatoid arthritis (57 sero positive), 19 had connective tissue diseases or vasculitis (six Sjögren's syndrome alone, six systemic sclerosis, three mixed connective tissue diseases, three polyarteritis, one relapsing polychondritis), and 22 patients had other inflammatory, metabolic or degenerative joint diseases. Lacrimal Ig and salivary Ig were assessed by double immunodiffusion with antisera specific for IgG, IgM and IgA. Each Ig class was scored on a scale ranging from 0 to 3 plus without knowledge of the patient's diagnosis. The results of factorial analysis demonstrated a strong relationship between xerophtalmia, positive Schirmer's test, s IgG, s IgM, 1 IgG, and 1 IgM in patients with seropositive rheumatoid arthritis or other connective tissue diseases. Analysis of individual parameters showed a significant relationship between 1 IgG and ocular complaints (P less than 0.01), positive Schirmer's test (P less than 0.05), positive rose bengal dye test (P less than 0.05), 1 IgM (P less than 0.01), s IgG (P less than 0.01) and s IgM (P less than 0.05). A significant relationship was also found between s IgG and ocular complaints (P less than 0.02), positive rose bengal dye test (P less than 0.01), positive minor salivary gland biopsy (P less than 0.05), s IgM (P less than 0.01), and 1 IgM (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)