AB0328 CLINICAL AND SEROLOGICAL DIFFERENCES BETWEEN PRIMARY SJOGREN’S SYNDROME PHENOTYPES
Authors: X. E. Larco Rojas, E. Diez Alvarez, C. Moriano, A. López Robles, T. Pérez Sandoval
Journal: Annals of the Rheumatic Diseases (2021)

Background: Primary Sjogren’s Syndrome (PSS) is an autoimmune and lymphoproliferative disease with a heterogeneous presentation. It has been postulated that there may be different phenotypes, in some cases presenting a more aggressive disease with systemic manifestations and a higher risk of developing complications. This phenotype has been associated with a higher autoimmune load and an earlier age of presentation. Furthermore, the presence of anti La + has been related to an increased risk of developing Lymphoma. Objectives: To describe the phenotypic characteristics of seronegative PSS in a sample of patients from our practice. To compare the clinical and laboratory characteristics between patients with Ro + / La + and Ro + / La- antibodies. To Analyze if there are differences in patients diagnosed at an early age, compared to a later age. Methods: Clinical and serological characteristics of patients with the diagnosis of PSS were collected from the Rheumatology database of León`s Hospital between 2014-2020. All patients who met the ACR / EULAR 2016 criteria were classified as seronegative Sjogren. In the group of patients with positive autoimmunity, anti-Ro + / La + were compared with the anti-Ro + / La- patients and by age, stratifying them into the following groups: 0-49; 50-69 and&gt; 70 years. The clinical variables analyzed were: glandular inflammation, Raynaud’s phenomenon (RP), pulmonary and neurological involvement, presence of Lymphoma and other tumours. The serological variables were: positivity of ANA, Rheumatoid Factor (RF), hypocomplementemia, hypergammaglobulinemia and B2 microglobulin. Results: 72 patients were analysed, 9 were excluded because didn’t meet the criteria. Of the remaining: 90,4% were women, with a mean age of 58,7+/-15,8 years, 12,6% (8) were seronegative. In the seronegative group 25% presented lung involvement (Lymphoid Interstitial Pneumonia), 50% presented with glandular inflammation and only one patient had RP. As complications 1 patient presented Lymphoma and 1 Breast Carcinoma. 58,7% (37) Ro + / La + and 28,5% (18) Ro + / La- patients were identified, no statistically significant differences were found between the two groups when comparing: glandular inflammation (8/37 vs 2/18, p = &gt;0.05) RP (9/37 vs 4/18, p = &gt;0.05), pulmonary involvement (5/37 vs. 6/18, p = &gt;0.05), neurological involvement (2/37 vs. 1/18, p = &gt;0.05), presence of Lymphoma (2/37 vs. 0 / 18, p = &gt;0,05), other tumours (2/37 vs 3/18, p = &gt;0.05), ANA positivity (36/37 vs 16/18, p =&gt;0,05), Hypocomplementemia (4/37 vs 3/18, p =&gt;0.05) and Hypergammaglobulinemia (20/37 vs 10/18, p =&gt;0.05). But a higher frequency of positive RF linked to anti La positivity (29/37 vs 6 / 18p = 0.002) was found. When comparing by age groups, the association between RF + and La + remained in the group of 50-69 years (15/18 vs 3/18, p = 0.002) while in the other age groups there were no statistically significant differences. We also observed an increasing trend of the levels of B2microglobulin in La+ patients and later age (p=0,04) Conclusion: The presence of anti La + seems to be associated with other components of autoimmunity such as RF in patients with PSS, although this study did not show a relation with a higher frequency of complications or systemic disease. Also, the presence of La+ at older ages was associated with higher levels of B2 microglobulin. We didn’t find differences with the other described markers of B cell reactivation. Findings differ from those found in the literature, which may be largely due to sample size. References: [1]Quartuccio L., Baldini C., Bartoloni E., et al. Anti-SSA/SSB-negative Sjogren’s syndrome shows a lower prevalence of lymphoproliferative manifestations, and a lower risk of lymphoma evolution. Autoimmunity Reviews 14 (2015) 1019–1022. [2]Quartuccio L, Isola M, Baldini C, Priori R, Bartoloni Bocci E, Carubbi F, et al. Biomarkers of lymphoma in Sjögren’s syndrome and evaluation of the lymphoma risk in prelymphomatous conditions: results of a multicenter study. J Autoimmun 2014; 51:75–80. Disclosure of Interests: None declared