[The value of FibroScan® in the follow-up of patients with chronic hepatitis B virus infection without indication for treatment]

Abstract

Transient elastography (TE) is a noninvasive method of assessing hepatic fibrosis in a quick, simple and reproducible manner. FibroScan is the best-known elastography apparatus and can assess a tissue volume 100 times greater than hepatic biopsy. Given that it lacks complications, TE can be repeated in the follow-up visit, thereby providing evolutionary information. One of its limitations, however, is its failure rate (4.5% of examinations), mainly in obese patients. TE has certain characteristics in chronic hepatitis B (HBV) infection. Transaminase levels and necroinflammation increase in reactivations, with hepatic stiffness increasing by 1.2 to 4.4 times. The second characteristic is related to macronodular cirrhosis caused by HBV, with less fibrous tissue compared with that produced by hepatitis C. Therefore, the cutoff values are smaller for hepatitis B than for hepatitis C. FibroScan helps categorize patients with chronic HBV infection into 4 fibrosis groups (approximate mean values and adding 1-2 more points with high transaminase levels): not significant (<6 kPa), grey area (6-9 kPa), significant (>9 kPa) and cirrhosis (>12 kPa). Thus, Fibroscan contributes to the treatment decision, and its repeated use during treatment enables us to verify that fibrosis has not progressed. In cases with no indication for treatment (chronic hepatitis with no criteria, inactive carrier state, immune-tolerant), the periodic reapplication of TE helps determine whether the inactivity continues or not. If the results are compatible with cirrhosis, hepatocarcinoma surveillance should be started.

Keywords: Elastografía de transición; FibroScan(®); Fibrosis hepática; HBV infection; Hepatic elasticity index; Hepatic fibrosis; Infección por virus B; Transient elastography; Índice de elasticidad hepática.