Asian-Pacific Association for the Study of the Liver (APASL) consensus guidelines on invasive and non-invasive assessment of hepatic fibrosis: a 2016 update.

Hepatic fibrosis is a common pathway leading to liver cirrhosis, which is the end result of any injury to the liver. Accurate assessment of the degree of fibrosis is important clinically, especially when treatments aimed at reversing fibrosis are being evolved. Despite the fact that liver biopsy (LB) has been considered the "gold standard" of assessment of hepatic fibrosis, LB is not favored by patients or physicians owing to its invasiveness, limitations, sampling errors, etc. Therefore, many alternative approaches to assess liver fibrosis are gaining more popularity and have assumed great importance, and many data on such approaches are being generated. The Asian Pacific Association for the Study of the Liver (APASL) set up a working party on liver fibrosis in 2007, with a mandate to develop consensus guidelines on various aspects of liver fibrosis relevant to disease patterns and clinical practice in the Asia-Pacific region. The first consensus guidelines of the APASL recommendations on hepatic fibrosis were published in 2009. Due to advances in the field, we present herein the APASL 2016 updated version on invasive and non-invasive assessment of hepatic fibrosis. The process for the development of these consensus guidelines involved review of all available published literature by a core group of experts who subsequently proposed consensus statements followed by discussion of the contentious issues and unanimous approval of the consensus statements. The Oxford System of the evidence-based approach was adopted for developing the consensus statements using the level of evidence from one (highest) to five (lowest) and grade of recommendation from A (strongest) to D (weakest). The topics covered in the guidelines include invasive methods (LB and hepatic venous pressure gradient measurements), blood tests, conventional radiological methods, elastography techniques and cost-effectiveness of hepatic fibrosis assessment methods, in addition to fibrosis assessment in special and rare situations.

Non-invasive assessment of portal hypertension and liver fibrosis using contrast-enhanced ultrasonography.

Portal hypertension and hepatic fibrosis are key pathophysiologies with major manifestations in cirrhosis. Although the degree of portal pressure and hepatic fibrosis are pivotal parameters, both are determined using invasive procedures. Ultrasound (US) is a simple and non-invasive technique that is available for use worldwide in the abdominal field. Because of its safety and easy of use, contrast-enhanced US is one of the most frequently used tools in the management of liver tumors for the detection and characterization of lesions, assessment of malignancy grade, and evaluation of therapeutic effects. This wide range of applications drives the practical use of contrast-enhanced US for evaluation of the severity of portal hypertension and hepatic fibrosis. The present article reviews the recent progress in contrast-enhanced US for the assessment of portal hypertension and hepatic fibrosis.

Effect of surgical portosystemic shunt on prevalence of minimal hepatic encephalopathy in children with extrahepatic portal venous obstruction: assessment by magnetic resonance imaging and psychometry.

OBJECTIVE: The aim of this study was to evaluate the effect of surgical portosystemic shunt (PSS) on the prevalence of minimal hepatic encephalopathy (MHE) in patients with extrahepatic portal venous obstruction. PATIENTS AND METHODS: Forty-two children with extrahepatic portal venous obstruction (17 with surgical PSS, 25 without surgical shunt) and 20 healthy children were evaluated with blood ammonia (BA), psychometry, H magnetic resonance spectroscopy, critical flicker frequency (CFF), and diffusion tensor imaging. Serum tumor necrosis factor-α and interleukin-6 were measured in 10 patients and 8 controls. RESULTS: Patients with surgical PSS had significantly higher BA and glutamine/creatine on H-MR spectroscopy than those without surgical shunt. Both groups of patients had significantly higher BA and glutamate/creatine than controls. Myoinositol was reduced in patients with surgical PSS. MHE was present in 41% cases with and 32% cases without surgical PSS (p-ns). Raised mean diffusivity on diffusion tensor imaging signifying low-grade cerebral edema was seen only in MHE cases. Patients had significantly higher serum tumor necrosis factor-α and interleukin-6 levels than controls. CFF was abnormal in 5 of 15 patients with MHE. CONCLUSIONS: Patients with surgical PSS have significantly higher BA and Glx/creatine than those without surgical PSS. MHE prevalence was higher in surgically shunted than in the nonshunted patients, but the difference was not significant. Cerebral edema is present in patients with MHE. CFF has limited diagnostic utility for MHE in children.

Encephalopathy assessment in children with extra-hepatic portal vein obstruction with MR, psychometry and critical flicker frequency.

BACKGROUND & AIMS: Mild cognitive and psychomotor deficit has been reported in patients with extra-hepatic portal vein obstruction. This prospective study was done to ascertain the presence of minimal hepatic encephalopathy by neuropsychological testing and its correlation with diffusion tensor imaging derived metrics, T1 signal intensity, brain metabolites in (1)H magnetic resonance spectroscopy, blood ammonia and critical flicker frequency in patients with extra-hepatic portal vein obstruction. METHODS: Neuropsychological tests, critical flicker frequency, blood ammonia, diffusion tensor imaging, T1 signal intensity and (1)H magnetic resonance spectroscopy were determined in 22 extra-hepatic portal vein obstruction and 17 healthy children. Bonferroni multiple comparison post hoc analysis was done to compare controls with patient groups. RESULTS: Based on neuropsychological tests, 7/22 patients had minimal hepatic encephalopathy, and significantly increased Glx/Cr ratio, blood ammonia, mean diffusivity and globus pallidus T1 signal intensity with decreased critical flicker frequency in comparison to controls and in those without minimal hepatic encephalopathy. Cho/Cr, mI/Cr ratio and fractional anisotropy were unchanged in patient groups compared to controls. A significant inverse correlation of neuropsychological test with mean diffusivity, Glx/Cr ratio and blood ammonia and a positive correlation among mean diffusivity, blood ammonia and Glx/Cr ratio was seen. CONCLUSIONS: Extra-hepatic portal vein obstruction is a true hyperammonia model with porto-systemic shunting and normal liver functions that results in minimal hepatic encephalopathy in one-third of these children. Hyperammonia results in generalized low grade cerebral edema and cognitive decline as evidenced by increased Glx/Cr ratio, mean diffusivity values and abnormal neuropsychological tests.