hepatic and biliary disorders
Hepatic Fibrosis
Diagnosis of Hepatic Fibrosis
Clinical evaluation Sometimes blood tests and/or noninvasive imaging tests Sometimes liver biopsy Hepatic fibrosis is suspected if patients have known chronic liver disease (eg, Hepatitis C, Chronic C [HCV] or chronic Tests used to stage fibrosis include conventional imaging tests, blood tests, liver biopsy, and newer noninvasive imaging tests that assess liver stiffness. Conventional imaging tests include ultrasonography, CT, and MRI. These tests can detect evidence of Cirrhosis and Noninvasive imaging assessment of fibrosis:Newer acoustic technologies can increase the accuracy of ultrasonography, CT, and MRI for detecting fibrosis or early cirrhosis; they include Ultrasonography None Ultrasonography None Ultrasonography None Magnetic resonance elastography (MRE) For these tests, acoustic vibrations are applied to the abdomen with a probe. How rapidly these vibrations are transmitted through liver tissue indicates how stiff (ie, fibrosed) the liver is. However, certain other conditions besides fibrosis also increase liver stiffness, including severe active Overview of Chronic Hepatitis , increased right heart pressures, and the postprandial state. Also, these techniques have not been validated well in pregnancy, sustained virologic response after HCV treatment, and rare liver disorders. Thus, use of these techniques is typically not recommended in patients with one of these conditions. To improve the assessment of fibrosis, other techniques (eg, corrected T1 MRI, 3-dimensional ultrasound-based measurement) are in development and awaiting validation in different clinical settings. remains the gold standard for diagnosing and staging hepatic fibrosis and for diagnosing the underlying liver disorder causing fibrosis. However, liver biopsy is invasive, resulting in a 10 to 20% risk of minor complications (eg, postprocedural pain) and a 0.5 to 1% risk of serious complications (eg, significant bleeding) ( Diagnosis references ). Also, liver biopsy is limited by sampling error and imperfect interobserver agreement in interpretation of histologic findings. Thus, liver biopsy may not always be done. Liver biopsy is usually not done solely for staging of hepatic fibrosis unless noninvasive tests do not help establish the diagnosis (eg, because different noninvasive tests yield discordant results) or for clinical trials. The METAVIR (meta-analysis of histological data in viral hepatitis) staging system assesses inflammatory changes (histologic activity) and the level of fibrosis as follows ( Diagnosis references ): Histologic activity A0 = no activity A1 = mild activity A2 = moderate activity A3 = severe activity Fibrosis F0 = no fibrosis F1 = portal fibrosis without septa F2 = portal fibrosis with rare septa F3 = numerous septa without cirrhosis F4 = cirrhosis Blood testsare included in clinical models (eg, APRI index, BARD score, FIB-4 score, nonalcoholic fatty liver disease [NAFLD] fibrosis score), which combine commonly available tests (AST, ALT, platelet count,albumin, INR) with demographic and clinical information (eg, age, body mass index [BMI], diabetes/impaired fasting glucose). Some commercially available panels (eg, FibroTest [known as Fibrosure in the United States], Hepascore, European Liver Fibrosis panel [ELF]) combine indirect markers (eg, serum bilirubin) and direct markers (eg, procollagen types I and III, hyaluronic acid) of hepatic function. Direct markers are substances involved in the pathogenesis of extracellular matrix deposition or cytokines that induce extracellular matrix deposition. These models and panels are best used to distinguish between 2 levels of fibrosis: absent to minimal vs moderate to severe; they do not accurately differentiate between degrees of moderate to severe fibrosis. Therefore, if fibrosis is suspected, one approach is to start with one of these panels and then do the newer noninvasive imaging assessments of fibrosis, reserving liver biopsy as a last resort. may improve the fibrosis assessment. Examples include the FAST (FibroScan- AST) score, which combines FibroScan and serum AST levels; MAST (MRI-AST) score, which combines the MRI-based proton density fat fraction (MRI-PDFF), MRE, and serum AST levels; and the MEFIB, which combines MRE and the Fibrosis-4 (FIB-4) index ( Diagnosis references ). These tools have been developed for assessment of hepatic fibrosis in 1.Thomaides-Brears HB, Alkhouri N, Allende D, et al: Incidence of complications from percutaneous biopsy in chronic liver disease: A systematic review and meta-analysis.DigDis Sci67(7):3366-3394, 2022. doi: 10.1007/s10620-021-07089-w 2.Bedossa P, Poynard T: An algorithm for the grading of activity in chronic hepatitis C. The METAVIR Cooperative Study Group.Hepatology24(2):289-293, 1996. doi: 10.1002/hep.510240201 3.Kim BK, Tamaki N, Imajo K, et al: Head-to-head comparison between MEFIB, MAST, and FAST for detecting stage 2 fibrosis or higher among patients with NAFLD.J Hepatol77(6):1482-1490, 2022. doi: 10.1016/j.jhep.2022.07.020 