QUANTITATIVE IMMUNOHISTOLOGIC CRITERIA ARE SUPERIOR TO THE LYMPHOCYTIC FOCUS SCORE CRITERION FOR THE DIAGNOSIS OF SJOGRENS-SYNDROME

Objective. The aim of the present study was to evaluate the diagnostic value of quantitative immunohistologic criteria for Sjogren's syndrome (SS) in labial salivary gland biopsies. Methods. Quantitative immunohistologic examination was performed on labial salivary gland biopsy samples from 80 healthy controls, 32 patients with primary SS, 14 patients with secondary SS, 5 with "probable" SS, 36 with keratoconjunctivitis sicca (KCS) with a lymphocytic focus score <1 on the lip biopsy, and 18 with rheumatoid arthritis (RA) without clinical evidence of SS. Results. This is the first study to show that immunohistologic criteria for SS, based on the percentages of IgA-containing and IgG-containing plasma cells, are able to 1) confirm the diagnosis of SS in labial salivary glands of KCS patients in the absence of grade IV lymphocytic adenitis; and 2) distinguish between a grade IV focal lymphocytic adenitis in the labial salivary glands of SS patients and of RA patients without SS. Conclusion. Quantitative immunohistologic criteria were shown to be much more sensitive and disease specific than the widely accepted grade IV lymphocytic adenitis criterion, which corresponds to a lymphocytic focus score > 1, and these criteria should be included in the international diagnostic criteria for Sjogren's syndrome.