[Clinical and immunological features of primary Sjögren's syndrome patients with positive anti-centromere protein B antibody].

OBJECTIVE: To investigate the clinical and immunological features of primary Sjögren's syndrome (pSS) patients with positive anti-centromere protein B (CENP-B) antibody.

METHODS: In this cross-sectional study, the general clinical data, radiographic examination and labial salivary gland biopsy data, and serum immunological and biochemical data of patients diagnosed with pSS from January 2016 to August 2022 were evaluated. The included patients were divided into the anti-CENP-B antibody positive and negative groups. Intergroup differences were analyzed with SPSS 23.0 software. Subgroup analysis was further performed by dividing the anti-CENP-B antibody positive group into the single anti-CENP-B antibody positive and with other auto-antibodies positive groups to determine the characters related to anti-CENP-B antibody.

RESULTS: In this study, 288 patients with pSS were evaluated, including 75 patients with anti-CENP-B antibody positive and 213 with anti-CENP-B antibody negative. Univariate analysis showed that compared with the anti-CENP-B antibody negative group, the patients of the anti-CENP-B antibody positive group were older, had lower proportion of the patients with salivary gland enlargement and higher proportion of autoimmune liver disease. As for immunological indicators, the positive proportions of anti-SSA/Ro60, anti-Ro52, and anti-SSB antibodies were significantly lower. Moreover, the immunoglobulin (Ig) G and rheumatoid factor levels were significantly lower, while the IgM level was significantly higher in the patients of the anti-CENP-B antibody positive group. As for serum biochemical indicators, for the patients of the anti-CENP-B antibody positive group, the level of total protein (TP) was lower, the albumin/globulin ratio was higher, and the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), lactate dehydrogenase (LDH) were higher. Subgroup analysis showed that the levels of TP and IgA in the patients of the single anti-CENP-B antibody positive group were significantly lower than those of the patients with other autoantibodies positive group.

CONCLUSION: The pSS patients with anti-CENP-B antibody positive have unique clinical and immunological features of lower disease activity, less likely to involve salivary gland, higher risk for autoimmune liver disease, and higher levels of liver function indicators. Anti-CENP-B antibody may be a marker for a distinct subset of polyautoimmunity in Sjögren's syndrome.