Usefulness of transient elastography for assessment of liver fibrosis in chronic hepatitis B: Regression of liver stiffness during entecavir therapy

Aim: The usefulness of transient elastography remains to be validated in chronic hepatitis B, particularly as a tool for monitoring the degree of liver fibrosis during treatment. Methods: The subjects were 50 patients with chronic hepatitis B virus infection. Liver biopsy was performed in 38 patients, and in 12 patients with platelet counts of 50 x 109/L or less, cirrhosis was clinically diagnosed on the basis of specific signs of portal hypertension. Liver stiffness was measured by transient elastography at baseline and after 12 months of treatment in 20 nucleos(t)ide-naive patients who started entecavir within 3 months after study entry. Results: Twenty (40%) patients were classified as F1, 10 (20%) as F2, 5 (10%) as F3, and 15 (30%) as F4 (cirrhosis). Median liver stiffness (interquartile range) was 7.0 kPa (5.6-9.4), 9.8 kPa (5.6-14.7), 9.8 kPa (7.6-12.9), and 17.3 kPa (8.2-27.6) in fibrosis stages F1 to F4, respectively. Liver stiffness significantly correlated with fibrosis stage (r = 0.46; P = 0.0014). Of the patients who started entecavir, median liver stiffness significantly decreased from 11.2 kPa (7.0-15.2) to 7.8 kPa (5.1-11.9; P = 0.0090) during 12 months of treatment. Median levels of amino-terminal peptide of type III procollagen and type IV collagen 7S domain in serum significantly decreased from 0.9 (0.6-1.3) to 0.6 (0.5-0.7) U/mL (P = 0.0010) and from 5.0 (4.4-6.7) to 3.9 (3.2-4.4) ng/mL (P = 0.015), respectively. Conclusion: Liver stiffness measurement can be useful for monitoring regression of liver fibrosis during entecavir treatment in patients with chronic hepatitis B virus infection.