Performance of transient elastography in assessing liver fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis overlap syndrome

AIM To investigate the performance of transient elastography(TE) for diagnosis of fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis(AIHPBC) overlap syndrome.METHODS A total of 70 patients with biopsy-proven AIH-PBC overlap syndrome were included. Spearman correlation test was used to analyze the correlation of liver stiffness measurement(LSM) and fibrosis stage. Independent samples Student’s t-test or one-way analysis of variance was used to compare quantitative variables. Receiver operating characteristics(ROC) curve was used to calculate the optimal cut-off values of LSM for predicting individual fibrosis stages. A comparison on the diagnostic accuracy for severe fibrosis was made between LSM and other serological scores.RESULTS Patients with AIH-PBC overlap syndrome had higher median LSM than healthy controls(11.3 ± 6.4 k Pa vs 4.3 ± 1.4 k Pa, P < 0.01). LSM was significantly correlated with fibrosis stage(r = 0.756, P < 0.01). LSM values increased gradually with an increased fibrosis stage. The areas under the ROC curves of LSM for stages F ≥ 2, F ≥ 3, and F4 were 0.837(95%CI: 0.729-0.914), 0.910(0.817-0.965), and 0.966(0.893-0.995), respectively. The optimal cut-off values of LSM for fibrosis stages F ≥ 2, F ≥ 3, and F4 were 6.55, 10.50, and 14.45 k Pa, respectively. LSM was significantly superior to fibrosis-4, glutaglumyl-transferase/platelet ratio, and aspartate aminotransferase-to-platelet ratio index scores in detecting severe fibrosis(F ≥ 3)(0.910 vs 0.715, P < 0.01; 0.910 vs 0.649, P < 0.01; 0.910 vs 0.616, P < 0.01, respectively).CONCLUSION TE can accurately detect hepatic fibrosis as a noninvasive method in patients with AIH-PBC overlap syndrome.