ObjectiveTo analyze the correlation of thrombopoietin (TPO) and anti-TPO antibody with thrombocytopenia in patients with primary Sjögren syndrome (PSS). MethodsWe included in our study 40 PSS patients with thrombocytopenia (group A), 22 PSS patients who once had thrombocytopenia and returned to normal (group B), 40 PSS patients with normal platelet counts (group C) and 40 healthy controls (group D) between September 2013 and October 2014. Anti-TPO antibody was detected by indirect enzyme-linked immunosorbent assay (ELISA), and serum TPO levels were measured by ELISA. We analyzed the relationship between the assay results and the clinical manifestations and parameters. ResultsThe serum TPO levels in groups A, B, and C were (129.74±17.47) , (330.23±18.07) and (364.19±12.25) pg/mL, respectively, and they were significantly higher than that in group D [(54.04±10.71) pg/mL] (P ＜ 0.05) . The serum level of TPO was positively correlated with CRP and IgA (rs=0.224, P=0.039; rs=0.239, P=0.033) , and was negatively correlated with C4 level (rs=?0.220, P=0.041) , but it was not significantly correlated with platelet count, erythrocyte sedimentation rate, the level of antiphospholipid antibodies and the titer of antinuclear antibodies (P ＞ 0.05) . The positive rate of PSS patients was 20.59% (21/102) and the rate in groups A, B, and C was respectively 17.5% (7/40) , 22.72% (5/22) , and 22.5% (9/40) . There was no statistically significant difference between the positive and negative groups in various clinical indexes (P ＞ 0.05) . ConclusionAntiTPO antibody may not be the main mechanism of thrombocytopenia in PSS patients, and there is a certain correlation between TPO and inflammatory factors.