On-treatment monitoring of liver fibrosis with transient elastography in chronic hepatitis B patients

Background: The performance of liver stiffness measurement (LSM) to monitor the changes in the severity of liver fibrosis in chronic hepatitis B (CHB) patients on antiviral treatment is uncertain. Methods: We prospectively studied CHB patients undergoing paired liver biopsy and transient elastography before and at week 48 of antiviral treatment. Based on our previously reported LSM algorithm, advanced liver fibrosis (F3-4) could be excluded or confirmed at >90% confidence. Results: A total of 71 CHB patients were studied. The median alanine aminotransferase (ALT) level decreased from 991 U/I to 331 U/I, and the median LSM decreased from 8.8 kPa to 6.6 kPa, respectively, from baseline to week 48. Overall, 17 and 11 patients had regression and progression of histological fibrosis, respectively. Areas under the receiver operating characteristics curves of the LSM algorithm at baseline and week 48 for advanced fibrosis were 0.80 (95% confidence interval [CI] 0.69-0.90) and 0.78 (95% CI 0.64-0.92), respectively. The sensitivity of LSM algorithm to exclude advanced fibrosis was 100% at baseline and 75% at week 48. The specificity of the LSM algorithm to diagnose advanced fibrosis was 84% at baseline and 91% at week 48. Overall, 11/28 (39%) patients with LSM that decreased by >30%, 28/41 (68%) of patients with LSM that changed within 30% and 1/2 (50%) patients with LSM that increased by >30% had decreased, unchanged and increased histological fibrosis stages, respectively. Conclusions: LSM could predict advanced fibrosis during antiviral therapy according to the ALT-based algorithm. Decrease in absolute LSM value, which could be related to ALT normalization, was unreliable to indicate regression of liver fibrosis.