Regression in liver stiffness measured by transient elastography (FibroScan) during entecavir treatment in patients with chronic hepatitis B

Aim: Entecavir is the most potent agent against hepatitis B virus (HBV) among licensed nucleos(t)ide analogs, and used as first‐line choice for treatment of chronic hepatitis B. Randomized, controlled trials showed not only virological and biochemical effects but also histological effects of entecavir. However, liver biopsy is not suitable for repeated evaluations, because it is invasive and associated with a risk of major complications. The aim of this study was to investigate whether transient elastography could be used for monitoring effects of entecavir on improvement of liver fibrosis in patients with chronic hepatitis B. Methods: The subjects were 50 consecutive patients (28 men and 22 women; mean age, 50 ± 13 years) with chronic hepatitis B in whom liver stiffness was successfully measured by transient elastography (FibroScan; EchoSens, Paris, France). In 38 of the 50 patients, liver biopsies were taken within 3 months of the liver stiffness measurement, and in 12 of the 50 patients with platelet count of 50 000/mm3 or less, cirrhosis was clinically diagnosed on the basis of specific signs of portal hypertension such as esophageal varices. In 20 of the 50 patients who started entecavir within 3 months after the entry, liver stiffness, as well as serum levels of amino‐terminal peptide of type III procollagen (PIIINP) and type IV collagen 7S domain, were measured at baseline and at 12 months of treatment. Results: Twenty (40%) patients were classified as F1, 10 (20%) as F2, five (10%) as F3 and 15 (30%) as F4/cirrhosis. Median liver stiffness (interquartile range) (kPa) were 7.0 (5.6‐9.4), 9.8 (5.6‐14.7), 9.8 (7.6‐12.9) and 17.3 (8.2‐27.6), respectively, in the fibrosis stages F1‐F4. Significant correlation was found between liver stiffness and fibrosis stage (P = 0.0014). Of the 20 patients treated with entecavir, median liver stiffness (interquartile range) significantly decreased from 11.2 (7.0‐15.2) to 7.8 (5.1‐11.9) kPa (P = 0.016) during the first 12 months of entecavir treatment. Median PIIINP levels significantly decreased from 0.9 (0.6‐1.3) to 0.6 (0.5‐0.7) U/mL (p = 0.0010). Median levels of type IV collagen 7S domain significantly decreased from 5.0 (4.4‐6.7) to 3.9 (3.2‐4.4) ng/mL (P = 0.015). Conclusion: Transient elastography is a rapid, objective and promising device for the staging of fibrosis by measuring liver stiffness in patients with chronic hepatitis B. Liver stiffness measurement can be useful for monitoring regression of the liver fibrosis during entecavir treatment for chronic hepatitis B.