目的: 分析抗干燥综合征抗原B (Sjögren ’ s syndrome type B, SSB)抗体阳性的原发性干燥综合征(primary Sjögren ’ s syndrome，pSS)患者与抗SSB抗体阴性的pSS患者之间临床表现及实验室指标的差异。方法: 回顾性收集2009—2019年于北京大学第三医院风湿免疫科住院的pSS患者的病历资料，采用t检验、Mann-Whitney秩和检验、卡方检验和Fisher确切概率法对抗SSB抗体阳性和抗SSB抗体阴性的pSS患者组的临床特征及实验室指标进行分析。结果: 共纳入pSS患者142例，其中女性137例，男性5例，平均年龄(54.8±13.3)岁，其中抗SSB抗体阳性患者44例(31.0%)。临床特征方面，抗SSB抗体阳性的pSS患者较抗体阴性患者的就诊年龄和起病年龄更小[就诊年龄：(50.9±14.5)岁vs. (56.5±12.4)岁，P < 0.05；起病年龄：(42.2±14.8)岁vs. (49.5±15.3)岁，P < 0.05]，出现皮疹(29.5% vs. 14.3%，P < 0.05)、腮腺肿大(27.3% vs. 8.2%，P < 0.05)、肾小管酸中毒(15.9% vs. 4.2%，P < 0.05)、免疫性血小板减少(9.1% vs. 1.0%，P < 0.05)的比例更高；两组患者在口干、眼干、雷诺现象(Raynaud phenomenon)等方面差异无统计学意义。实验室指标方面，抗SSB抗体阳性组患者与阴性组患者相比，类风湿因子(rheumatoid factor, RF)阳性率(85.0% vs. 49.4%, P < 0.05)及滴度(中位数89.8 IU/mL vs. 20.5 IU/mL，P < 0.05)、抗核抗体(antinuclear antibody，ANA)滴度(中位数320 vs. 160，P < 0.05)、抗干燥综合征抗原A (Sjögren ’ s syndrome type A, SSA)抗体阳性率(97.7% vs. 64.3%, P < 0.05)、IgG水平(中位数21.0 g/L vs. 15.6 g/L，P < 0.05)、γ球蛋白升高率(71.4% vs. 38.5%，P < 0.05)、CD3^-CD19⁺细胞比例[(21.0±11.9)% vs. (13.7±9.6)%，P < 0.05]均更高，而CD3⁺细胞比例[(67.2±14.4)% vs. (76.6±13.1)%，P < 0.05]和抗线粒体抗体M2亚型阳性率(10.5% vs. 35.6%，P < 0.05)相对更低，其余无明显差异。治疗方面，与抗SSB抗体阴性组患者相比，抗SSB抗体阳性组患者应用激素(90.9% vs. 73.5%，P < 0.05)及免疫抑制剂(54.5% vs. 36.7%，P < 0.05)的比例更高。结论: 与抗SSB抗体阴性pSS患者相比，抗SSB抗体阳性患者的起病年龄更小，临床表现更多样，血清其他自身抗体阳性率/水平及B细胞活化程度更高，治疗上需要应用激素及免疫抑制剂的概率更大，整体倾向于表现出更重的临床表型。

Objective: To analyze the differences of clinical manifestations and laboratory features between primary Sjögren’s syndrome (pSS) patients with positive and negative anti-Sjögren’s syndrome type B (SSB) antibody. Methods: The clinical data of pSS patients hospitalized in Department of Rheumato-logy and Immunology, Peking University Third Hospital were retrospectively analyzed to investigate the differences of clinical and laboratory features between anti-SSB positive and negative groups. The t test, Mann-Whitney U test, Chi-square test and Fisher’s exact probability were used for analysis. Results: A total of 142 pSS patients were enrolled in this study, including 137 females and 5 males with a mean age of (54.8±13.3) years. The anti-SSB positive group included 44 patients accounting for 31.0% of the pSS patients. The anti-SSB positive pSS patients were younger at disease onset and at visit [age at visit: (50.9±14.5) years vs. (56.5±12.4) years; age at onset: (42.2±14.8) years vs. (49.5±15.3) years, P < 0.05]. The patients with anti-SSB positive more frequently presented with rash (29.5% vs. 14.3%, P < 0.05), enlargement of parotid glands (27.3% vs. 8.2%, P < 0.05), renal tubular acidosis (15.9% vs. 4.2%, P < 0.05), immune thrombocytopenia (9.1% vs. 1.0%, P < 0.05), rheumatoid factor (RF) positive (85.0% vs. 49.4%, P < 0.05), higher RF and antinuclear antibody (ANA) titers (median: 89.8 IU/mL vs. 20.5 IU/mL; median: 320 vs. 160, P < 0.05), anti-Sjögren’s syndrome type A (SSA) antibody positive (97.7% vs. 64.3%, P < 0.05), elevation of γ globulin (71.4% vs. 38.5%, P < 0.05), higher levels of IgG (median: 21.0 g/L vs. 15.6 g/L, P < 0.05), higher proportions of CD3^-CD19⁺ cells [(21.0±11.9)% vs. (13.7±9.6)%, P < 0.05] and lower proportions of CD3⁺ cells [(67.2±14.4)% vs. (76.6%±13.1)%, P < 0.05] than those negative. However, the anti-SSB positive group was less likely to show anti-mitochondrial antibodies (AMA)-M2 positivity (10.5% vs. 35.6%, P < 0.05). Glucocorticoids (90.9% vs. 73.5%, P < 0.05) and immunosuppressants (54.5% vs. 36.7%, P < 0.05) were more frequently used in anti-SSB positive pSS patients than those negative. Conclusion: The anti-SSB positive pSS patients were younger at disease onset while more frequently presenting with various symptoms, higher levels of other antibodies and activation of B cells than those negative. Glucocorticoids and immunosuppressants were more frequently used, indicating that anti-SSB positive group presented with a more severe clinal phenotype.