Association of unstimulated salivary flow rate and labial salivary gland histopathology with serologic features of Sjögren’s syndrome

Abstract

Sjögren’s syndrome (SS) is a chronic autoimmune disorder with its major clinical manifestation resulting from changes in exocrine glands. An autoimmune etiology of SS is supported by the presence of autoantibodies specific for nuclear anti Ro (SS-A) and anti La (SS-B) antigens and other antinuclear antibodies (ANA) in sera of SS patients. The aim of the study was to evaluate the frequency of positive values of anti SS-A, anti SS-B antibodies and ANA in serum of 40 SS patients, and to correlate the above mentioned parameters with unstimulated salivary flow rate (USFR) and labial salivary gland focus score (LFS). Total of 40 patients was included in this research, 23 patients with primary SS and 17 with secondary SS. ANA was detected by the method of indirect immunofluorescence, and anti Ro/SS-A and anti La/SS-B antibodies were quantified by sandwich (Elisa) assay. The positive values of ANA were identified in plasma of 32 examined SS patients (80%), anti SS-A (Ro-52 kDa, Ro-60 kDa) antibodies were positive by 22 patients (55%), and anti SS-B antibodies were positive in less then 50% of examined SS patients (40%). The most presented were the patients with medium expressed xerostomia. Significant correlation between the unstimulated salivary flow rate and the positive values of ANA, anti Ro/SS-A, and anti La/SS-B antibodies could not be noticed. With increasing severity of disease there was an increase of the number of lymphocyte foci and a progressive loss of acinar tissue. High level of anti Ro/SS-A antibodies was found more often in plasma of the SS patients in a case of progressive loss of acinar tissue of the salivary gland (terminal stage), with statistical significance. It was concluded that the increased prevalence of positive values of anti Ro/SS-A antibodies and ANA indicates that the patient with SS has developed higher level of autoimmune reactivity. Level of anti Ro/SS-A antibodies in the peripheral blood of the patient with SS could be a significant marker of the degree of salivary/tissue destruction and disease severity.