Abstract: Objective To explore the diagnostic efficacy and influencing factors of two-dimensional shear wave elastography (2D-SWE) in autoimmune liver disease (AILD). Methods The clinical data of AILD patients pathologically confirmed by aspiration liver biopsy and grouped as autoimmune hepatitis (AIH) group, primary biliary cholangitis (PBC) group, and overlap syndrome (OS) group were retrospective analyzed, including liver 2D-SWE value, pathological S grade, essential information such as age and gender, ultrasound echo of liver parenchyma and size of spleen, blood routine and biochemistry, immunity inspection index, and so on. Pearson or Sperman rank method was used for correlation analysis between groups. Receiver working curve (ROC) was drawn and the diagnostic cut-off value was found according to Youden index, the sensitivity and specificity were calculated, and Linear regression was used for analyzing the influencing factors. Results There were 107 AILD patients, including 21 in AIH group, 58 in PBC group, and 28 in OS group. Liver 2D-SWE value were 7.4(5.2, 9.8)kPa. Median BMI was (22.6±2.8) kg/m². 26 patients had splenomegaly, hemoglobin (Hb) (122.3±17.0) g/L, alanine aminotransferase (ALT) 79(41, 150)IU/L, aspartate aminotransferase (AST) 72(43, 132)IU/L, total bilirubin 18.6(11.9, 46.1)μmol/L, IgG 18.40(15.18, 23.15)mg/mL. Pathological S classification: 79 patients were grade 0~2 and 28 patients of them were in overall group; 10 patients were grade 0~2 and 11 patients were grade 3~4 in AIH group; 53 patients were grade 0~2 and 5 patients were grade 3~4 in PBC group; 16 patients were grade 0~2 and 12 patients were grade 3~4 in OS group. The liver 2D-SWE values were positively correlated with the pathological fibrosis grade in the overall, PBC and OS groups (r=0.431, P<0.001; r=0.279, P=0.034; r=0.442, P=0.018, respectively). If S≥3, the area under curve of the three groups were 0.783, 0.787 and 0.758, the diagnostic cut-offs were 7.35 kPa, 7.6 kPa, 9.3 kPa, the sensitivity and specificity were 89.3%, 63.3%; 80.0%, 75.5%; 83.3% and 75.0%, respectively. Univariate analysis showed age (P=0.040), splenomegaly (P=0.007), BMI (P=0.007), Hb (P=0.003), AST (P=0.005), total bilirubin (P<0.001), IgG (P<0.001) were influencing factors for 2D-SWE values, multiplicity analysis showed splenomegaly (P=0.013), total bilirubin (P=0.004) and IgG (<0.001) were independent influencing factors. Conclusion 2D-SWE can be used to distinguish mild to moderate fibrosis from severe fibrosis in AILD patients, especial in PBC and OS patients, which is affected by size of spleen, bilirubin and IgG levels.

Key words: Two-dimensional shear wave elastography, Autoimmune liver disease, Liver fibrosis, Diagnosis, Influencing factors