Association of mast cells with fibrosis and fatty infiltration in the minor salivary glands of patients with Sjogren's syndrome

Objective To determine the distribution and density of mast cells in the minor salivary glands of patients with primary Sjogren's syndrome (pSS) and of normal controls. Methods Minor salivary gland biopsies were obtained from 19 patients with pSS, 9 with systemic lupus erythematosus, one each with rheumatoid arthritis, sarcoidosis, and Hodgkin's disease, and from 10 individuals who had subjective xerostomia with normal salivary gland biopsies. Biopsy specimens were evaluated for the degree of inflammation according to Tarpley's classification. Sections were analysed for staining with Toluidine blue and with the mast cell specific marker c-kit. The data obtained were correlated with the histological findings of fatty infiltration, fibrosis and lymphocytic infiltration. Results There was a significant correlation between the number of mast cells identified and the degrees of fibrosis and fatty infiltrates. There was no correlation between the intensity of lymphoid infiltration and the number of mast cells. c-kit staining showed a high correlation when compared to Toluidine blue staining. Conclusion Mast cells in the minor salivary glands of patients with pSS are strongly associated with fibrosis and cell acid infiltration. However, there is no correlation with parameters of disease activity such as lymphoid infiltration.