Optimal time for restoring the reliability of liver stiffness measurement in patients with chronic hepatitis B experiencing acute exacerbation

BACKGROUND/AIMS: Liver stiffness measurement (LSM) using transient elastography (FibroScan) is influenced by major changes in aminotransferase. We aimed to determine the optimal time for restoring the reliability of LSM for assessing liver fibrosis in patients with chronic hepatitis B experiencing acute exacerbation. METHODS: Twenty-one patients with acute exacerbation of chronic hepatitis B [alanine aminotransferase (ALT)>5× upper limit of normal (ULN)] were prospectively recruited. Serial LSM and biochemical tests were performed at the time of admission and after 1, 3, 6, 9, and 12 months. The ULN of ALT was defined as 40 IU/L. The cutoff LSM value for cirrhosis was defined as 10.3 kPa. RESULTS: The median age (9 male) was 49 years. The median ALT and LSM in the baseline were 522 IU/L and 15.1 kPa, respectively. Three months after acute exacerbation, ALT had decreased significantly below 2× ULN and stabilized (median: 522, 43, 21, 19, 18, and 16 IU/L at baseline, 1, 3, 6, 9, and 12 mo, respectively). However, LSM needed 3 more months (6 mo after exacerbation) for stabilization (median: 15.1, 10.0, 7.4, 7.1, 6.3, and 5.8 kPa at baseline, 1, 3, 6, 9, and 12 mo, respectively). CONCLUSIONS: LSM should be postponed for at least 3 months after stabilization of ALT below 2× ULN to restore the reliability of LSM in assessing liver fibrosis.