Reliability of Transient Elastography-Based Liver Stiffness for Diagnosing Portal Hypertension in Patients with Alcoholic Liver Disease: A Diagnostic Meta-Analysis with Specific Cut-Off Values

Non-invasive tools for compensated advanced chronic liver disease and portal hypertension after Baveno VII - an update

Non-invasive tests (NITs) and liver stiffness measurement (LSM) in particular, have entered clinical practice over 20 years ago as point-of-care tests to diagnose liver fibrosis in patients with compensated chronic liver disease. Since then, NITs use has evolved thanks to a large number of studies in all major etiologies of liver disease, and they have become important tools to stratify the risk of portal hypertension and liver-related events. The Baveno VII consensus workshop provided several novel recommendations regarding the use of well-established and novel NITs in the specific setting of portal hypertension screening, diagnosis and follow-up. The Baveno VII expert panels paid special attention to summarizing the existing data into simple clinical rules able to guide clinicians in their practice. The "rule of five" for LSM is a tool to stratify the risk of liver-related events, and LSM alone or in combination with platelet count, can be used now to rule-in and rule-out compensated advanced chronic liver disease (cACLD) and clinically significant portal hypertension, as well as to rule-out high-risk varices. Use of NITs in obese subjects with non-alcoholic fatty liver disease (NAFLD) and patients with viral hepatitis C that has been successfully treated, require specific knowledge. This review will update the reader on these aspects.

Application of Ultrasound Elastography in Assessing Portal Hypertension

Portal hypertension is a common manifestation in late-to-end-stage liver diseases and can cause severe complications such as ascites, hepatic encephalopathy, etc. However, an early diagnosis of portal hypertension is often difficult as it can be asymptomatic. Though the gold standard to diagnose portal hypertension is hepatic vein catheterization, ultrasound elastography is regarded as a noninvasive alternative that can be used to accurately predict portal hypertension and a few further complications such as gastro-esophageal varices. Since ultrasound elastography is available in most medical centers, and is cheaper and noninvasive, studying its function in predicting portal hypertension is of paramount importance. Therefore, this review generalized the results of recently published articles in order to establish the indicators that were related to diagnostic and prediction efficiency. Our study found that various technologies of ultrasound elastography could be used to predict portal hypertension with satisfactory diagnostic sensitivity, specificity, accuracy, and AUC. Meanwhile, we also recognized similar diagnostic efficiency of ultrasound elastography in gastro-esophageal varices.

Portal hypertension in nonalcoholic fatty liver disease: Challenges and perspectives

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. NAFLD‐related cirrhosis is often complicated by portal hypertension (PHT). Recent evidence showed that portal venous pressure (PVP) starts to rise in the early stages of NAFLD, even in absence of advanced fibrosis or cirrhosis. However, the precise pathological mechanisms of this process are still poorly understood. Lipid accumulation, hepatocellular ballooning, sinusoidal endothelial cell dysfunction, capillarization, microthrombosis, increased angiogenesis, and pericellular fibrosis may all be involved in the early development of increased PVP in NAFLD. Direct measurement of PHT is invasive and impractical in noncirrhotic NAFLD individuals and may also underestimate its severity. Thus, the development and validation of noninvasive and more accurate measurements, including new serum biomarkers, scoring models, and imaging techniques (such as ultrasonography, elastography, and magnetic resonance imaging), are urgently needed. Owing to the increasing morbidity, challenges in the prevention and management of PHT in NAFLD are unprecedented. This review article aims to briefly discuss these challenges and summarizes the mechanisms, diagnosis, and emerging therapies for PHT in people with NAFLD.

Resistance to thrombomodulin correlates with liver stiffness in chronic liver disease a prospective single-center cohort study

INTRODUCTION

Chronic liver disease (CLD) is characterized by changes in haemostasis, embracing both hypo- and hypercoagulability. Global hemostatic tests such as thrombin generation assays evaluate the hemostatic balance, to better assess bleeding and thrombotic risks. In addition, procoagulant state in patients with CLD has been demonstrated using modified thrombin generation assays with thrombomodulin, a cofactor for protein C activation. In this study, we prospectively determined thrombin generation and thrombomodulin resistance in patients with CLD staged with liver stiffness measurement (LSM), using both the fully automated analyzer ST Genesia® Thrombin Generation System (STG) and the calibrated automated thrombogram assay (CAT).

MATERIALS AND METHODS

Demographic, clinical and laboratory characteristics, and blood samples were collected from 65 patients with CLD. Liver stiffness was measured by transient elastography, and thrombin generation and thrombomodulin resistance, by STG and CAT.

RESULTS

Patients were separated based on LSM of <21 and ≥21 kilopascals (kPa). The propagation rate of thrombin generation was higher in patients with LSM ≥21 kPa and the thrombin generation rate increased as LSM increased. In addition, thrombomodulin resistance assessed by STG and CAT was higher in patients with LSM ≥21 kPa. However, ETP inhibition by activated protein C was comparable in patients with LSM <21 and ≥21 kPa. Finally, LSM correlated with most thrombin generation parameters.

CONCLUSION

The STG automated system may have value in the assessment of patients with chronic liver disease in the routine coagulation laboratory. LSM ≥21 kPa identify a procoagulant phenotype in these patients, including thrombomodulin resistance.

EASL Clinical Practice Guidelines on non-invasive tests for evaluation of liver disease severity and prognosis - 2021 update

Non-invasive tests are increasingly being used to improve the diagnosis and prognostication of chronic liver diseases across aetiologies. Herein, we provide the latest update to the EASL Clinical Practice Guidelines on the use of non-invasive tests for the evaluation of liver disease severity and prognosis, focusing on the topics for which relevant evidence has been published in the last 5 years.

Noninvasive Detection of Clinically Significant Portal Hypertension in Compensated Advanced Chronic Liver Disease

Patients with compensated advanced chronic liver disease have different prognoses depending on the presence of portal hypertension. Current non-invasive diagnostic methods allow identification of clinically significant portal hypertension. Portosystemic collaterals on imaging or liver stiffness of more than 20 to 25 kPa by using transient elastography identifies patients with clinically significant portal hypertension. Patients with liver stiffness of less than 20 kPa and platelet count of greater than 150 g/L can avoid endoscopy. This rule could be expanded using spleen stiffness. Methods to risk stratify for portal hypertension in compensated advanced chronic liver disease and successfully treated chronic hepatitis C and B are subject of research.

Validation and comparison of non-invasive prediction models based on liver stiffness measurement to identify patients who could avoid gastroscopy

Several non‐invasive tests (NITs) based on liver stiffness measurement (LSM) have been developed to rule out varices needing treatment (VNT), including the Baveno VI criteria (B6C), the expanded Baveno VI criteria (EB6C), the LSM-spleen diameter to platelet ratio score (LSPS), and the VariScreen algorithm. We aimed to validate and compare those NITs in patients with compensated advanced chronic liver disease (cACLD). This retrospective study enrolled 354 patients with cACLD; LSM, platelet count (PLT), international normalized ratio (INR), gastroscopy and spleen diameter (SD) were collected. VNT prevalence was 28.5%. In comparison, patients with VNT included higher LSM, INR, and SD and lower PLT. Gastroscopies were spared for 27.7% of patients using the B6C with 1.0% VNT missed rate, 47.2% of patients using the EB6C with 5.9% VNT missed rate, 57.6% of patients using the LSPS with 9.9% VNT missed rate, and 45.5% of patients using the VariScreen algorithm with 3.0% VNT missed rate. Only the B6C and the VariScreen algorithm could safely avoid gastroscopies, and the VariScreen algorithm spared more gastroscopies than the B6C. The results were consistent with the previous when performed subgroup analysis. In conclusion, the VariScreen algorithm performed the best and can be used in clinical.

Primary prevention of bleeding from esophageal varices in patients with liver cirrhosis: An update and review of the literature

All patients with liver cirrhosis and portal hypertension should be stratified by risk groups to individualize different therapeutic strategies to increase the effectiveness of treatment. In this regard, the development of primary prophylaxis of variceal bleeding and its management according to the severity of portal hypertension may be promising. This paper is to describe the modern principles of primary prophylaxis of esophageal variceal bleeding in patients with liver cirrhosis. The PubMed and EMbase databases, Web of Science, Google Scholar, and the Cochrane Database of Systematic Reviews were used to search for relevant publications from 1999 to 2019. The results suggested that depending on the severity of portal hypertension, patients with cirrhosis should be divided into those who need preprimary prophylaxis, which aims to prevent the formation of esophageal varices, and those who require measures that aim to prevent esophageal variceal bleeding. In subclinical portal hypertension, therapy should be etiological and pathogenetic. Cirrhosis with clinically significant portal hypertension should receive nonselective β-blockers if they have small esophageal varices and risk factors for variceal bleeding. Nonselective β-blockers are the first-line drugs for the primary prevention of bleeding from medium to large-sized esophageal varices. Endoscopic band ligation is indicated for the patients who are intolerant to nonselective β-blockers or in the case of contraindications to pharmacological therapy. In summary, the stratification of cirrhotic patients by the severity of portal hypertension and an individual approach to the choice of treatment may increase the effectiveness of therapy as well as improve survival rate of these patients.

Endogenous motion of liver correlates to the severity of portal hypertension

BACKGROUND

Degree of portal hypertension (PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH (CSPH) and severe PH (SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient (HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.

AIM

To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.

METHODS

Of 36 patients with liver cirrhosis and measured HVPG were included in the case-control study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal (d_antero, d_retro, d_RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain µ and standard deviation σ of strain were assessed in the regions of interest (ROI) (1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion (0-10 Hz and 10-20 Hz).

RESULTS

Four parameters showed statistically significant (P < 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain (estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only d_retro showed significant results in SPH analysis. According to ROC analysis area under the curve (AUC) of the σ_{ROI[0…10Hz, 2 cm × 2 cm]} parameter reached 0.71 (P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for µ_{ROI[0…10Hz, 1 cm × 1 cm]} was 0.78 (P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. D_retro parameter had an AUC of 0.86 (P = 0.0001) for the diagnosis of CSPH and 0.84 (P = 0.0001) for the diagnosis of SPH. A cut-off value of -132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.

CONCLUSION

The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH.