Current knowledge in pathophysiology and management of Budd-Chiari syndrome and non-cirrhotic non-tumoral splanchnic vein thrombosis

Budd-Chiari Syndrome (BCS) and non-cirrhotic non-tumoral portal vein thrombosis (NCPVT) are two rare disorders, with several similarities that are categorized under the term splanchnic vein thrombosis. Both disorders are frequently associated with an underlying pro-thrombotic disorder. They can cause severe portal hypertension and usually affect oung patients, negatively influencing life expectancy when the diagnosis and treatment is not done at an early stage. Yet, they have specific features that require individual considerations. The current review will focus on the available knowledge on pathophysiology, diagnosis and management of both entities. BCS is defined as the obstruction of hepatic venous outflow regardless of its causative mechanism or level of obstruction. This obstruction can be traced to the small hepatic venules up to the entrance of the inferior vein cava (IVC) into the right atrium. Hepatic outflow obstruction related to cardiac disease, pericardial disease or sinusoidal obstruction syndrome have different pathophysiological and clinical implications and are excluded from this definition. BCS is classified as primary when the obstruction originates in the vein and thrombosis is the main cause, or secondary when the vein is externally compressed (abscess, tumor). The focus of this review is on primary BCS. NCPVT refers to the presence of a thrombus in the main portal vein trunk and/or the left or right intrahepatic portal vein branches that may extend to the splenic vein and/or the superior or inferior mesenteric veins. Isolated splenic or mesenteric vein thrombosis are out of the scope of this review.Copyright © 2019. Published by Elsevier B.V

Review: Vascular effects of PPARs in the context of NASH.

BACKGROUND Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors known to regulate glucose and fatty acid metabolism, inflammation, endothelial function and fibrosis. PPAR isoforms have been extensively studied in metabolic diseases, including type 2 diabetes and cardiovascular diseases. Recent data extend the key role of PPARs to liver diseases coursing with vascular dysfunction, including nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). AIM This review summarises and discusses the pathobiological role of PPARs in cardiovascular diseases with a special focus on their impact and therapeutic potential in NAFLD and NASH. RESULTS AND CONCLUSIONS PPARs may be attractive for the treatment of NASH due to their liver-specific effects but also because of their efficacy in improving cardiovascular outcomes, which may later impact liver disease. Assessment of cardiovascular disease in the context of NASH trials is, therefore, of the utmost importance, both from a safety and efficacy perspective

EASL Clinical Practice Guidelines on prevention and management of bleeding and thrombosis in patients with cirrhosis

: The prevention and management of bleeding and thrombosis in patients with cirrhosis poses several difficult clinical questions. These Clinical Practice Guidelines have been developed to provide practical guidance on debated topics, including current views on haemostasis in liver disease, controversy regarding the need to correct thrombocytopenia and abnormalities in the coagulation system in patients undergoing invasive procedures, and the need for thromboprophylaxis in hospitalised patients with haemostatic abnormalities. Multiple recommendations in this document are based on interventions that the panel feels are not useful, even though widely applied in clinical practice

Hepatocyte tissue factor contributes to the hypercoagulable state in a mouse model of chronic liver injury

Patients with chronic liver disease and cirrhosis have a dysregulated coagulation system and are prone to thrombosis. The basis for this hypercoagulable state is not completely understood. Tissue factor (TF) is the primary initiator of coagulation in vivo. Patients with cirrhosis have increased TF activity in white blood cells and circulating microparticles. The aim of our study was to determine the contribution of TF to the hypercoagulable state in a mouse model of chronic liver injury

Characterization of Blood Immune Cells in Patients With Decompensated Cirrhosis Including ACLF

Background and Aims: Patients with cirrhosis and acute-on-chronic liver failure (ACLF) have immunosuppression, indicated by an increase in circulating immune-deficient monocytes. The aim of this study was to investigate simultaneously the major blood-immune cell subsets in these patients. Material and Methods: Blood taken from 67 patients with decompensated cirrhosis (including 35 critically ill with ACLF in the intensive care unit), and 12 healthy subjects, was assigned to either measurements of clinical blood counts and microarray (genomewide) analysis of RNA expression in whole-blood; microarray (genomewide) analysis of RNA expression in blood neutrophils; or assessment of neutrophil antimicrobial functions. Results: Several features were found in patients with ACLF and not in those without ACLF. Indeed, clinical blood count measurements showed that patients with ACLF were characterized by leukocytosis, neutrophilia, and lymphopenia. Using the CIBERSORT method to deconvolute the whole-blood RNA-expression data, revealed that the hallmark of ACLF was the association of neutrophilia with increased proportions of macrophages M0-like monocytes and decreased proportions of memory lymphocytes (of B-cell, CD4 T-cell lineages), CD8 T cells and natural killer cells. Microarray analysis of neutrophil RNA expression revealed that neutrophils from patients with ACLF had a unique phenotype including induction of glycolysis and granule genes, and downregulation of cell-migration and cell-cycle genes. Moreover, neutrophils from these patients had defective production of the antimicrobial superoxide anion. Conclusions: Genomic analysis revealed that, among patients with decompensated cirrhosis, those with ACLF were characterized by dysregulation of blood immune cells, including increases in neutrophils (that had a unique phenotype) and macrophages M0-like monocytes, and depletion of several lymphocyte subsets (including memory lymphocytes). All these lymphocyte alterations, along with defective neutrophil superoxide anion production, may contribute to immunosuppression in ACLF, suggesting targets for future therapies

EASL-ERN position paper on liver involvement in patients with Fontan-type circulation

Fontan-type surgery is the final step in the sequential palliative surgical treatment of infants born with a univentricular heart. The resulting long-term haemodynamic changes promote liver damage, leading to Fontan-associated liver disease (FALD), in virtually all patients with Fontan circulation. Owing to the lack of a uniform definition of FALD and the competitive risk of other complications developed by Fontan patients, the impact of FALD on the prognosis of these patients is currently debatable. However, based on the increasing number of adult Fontan patients and recent research interest, the European Association for The Study of the Liver and the European Reference Network on Rare Liver Diseases thought a position paper timely. The aims of the current paper are: (1) to provide a clear definition and description of FALD, including clinical, analytical, radiological, haemodynamic, and histological features; (2) to facilitate guidance for staging the liver disease; and (3) to provide evidence- and experience-based recommendations for the management of different clinical scenarios.</p

EASL-ERN position paper on liver involvement in patients with Fontan-type circulation

Fontan-type surgery is the final step in the sequential palliative surgical treatment of infants born with a univentricular heart. The resulting long-term haemodynamic changes promote liver damage, leading to Fontan-associated liver disease (FALD), in virtually all patients with Fontan circulation. Owing to the lack of a uniform definition of FALD and the competitive risk of other complications developed by Fontan patients, the impact of FALD on the prognosis of these patients is currently debatable. However, based on the increasing number of adult Fontan patients and recent research interest, the European Association for The Study of the Liver and the European Reference Network on Rare Liver Diseases thought a position paper timely. The aims of the current paper are: (1) to provide a clear definition and description of FALD, including clinical, analytical, radiological, haemodynamic, and histological features; (2) to facilitate guidance for staging the liver disease; and (3) to provide evidence- and experience-based recommendations for the management of different clinical scenarios.</p

2D shear wave liver elastography by aixplorer to detect portal hypertension in cirrhosis: an individual patient data meta-analysis

Background & Aims: Liver stiffness measured with 2-dimensional shear wave elas- tography by Supersonic Imagine (2DSWE-SSI) is well-established for fibrosis diagnos- tics, but non-conclusive for portal hypertension. Methods: We performed an individual patient data meta-analysis of 2DSWE-SSI to identify clinically significant portal hypertension (CSPH), severe portal hyperten- sion and large varices in cirrhosis patients, using hepatic venous pressure gradient and upper endoscopy as reference. We used meta-analytical integration of diagnos- tic accuracies with optimized rule-out (sensitivity-90%) and rule-in (specificity-90%) cut-offs. Results: Five studies from seven centres shared data on 519 patients. After exclu- sion, we included 328 patients. Eighty-nine (27%) were compensated and 286 (87%) had CSPH. 2DSWE-SSI < 14 kPa ruled out CSPH with a summary AUROC (sROC), sensitivity and specificity of 0.88, 91% and 37%, and correctly classified 85% of pa- tients, with minimal between-study heterogeneity. The false negative rate was 60%, of which decompensated patients accounted for 78%. 2DSWE-SSI ≥ 32 kPa ruled in CSPH with sROC, sensitivity, specificity and correct classifications of 0.83, 47%, 89% and 55%. In a subgroup analysis, the 14 kPa cut-off showed consistent sensitivity and higher specificity for patients with compensated cirrhosis, without ascites, viral 2 aetiology or BMI < 25 kg/m . 2DSWE-SSI ruled out severe portal hypertension and large varices with fewer correctly classified and lower sROC, and with minimal benefit for ruling in. Conclusion: Liver stiffness using 2-dimensional shear wave elastography below 14 kPa may be used to rule out clinically significant portal hypertension in cirrhosis patients, but this would need validation in populations of compensated liver disease. 2DSWE-SSI cannot predict varices needing treatment

J Thromb Haemost

Essentials To reliably study the respective roles of blood and endothelial cells in hemostasis, mouse models with a strong and specific endothelial expression of the Cre recombinase are needed. Using mT/mG reporter mice and conditional JAK2 mice, we compared Pdgfb-iCreERT2 and Cdh5(PAC)-CreERT2 with well-characterized Tie2-Cre mice. Comparison of recombination efficiency and specificity towards blood lineage reveals major differences between endothelial transgenic mice. Cre-mediated recombination occurs in a small number of adult hematopoietic stem cells in Pdgfb-iCreERT2;JAK2 transgenic mice. SUMMARY: Background The vessel wall, and particularly blood endothelial cells (BECs), are intensively studied to better understand hemostasis and target thrombosis. To understand the specific role of BECs, it is important to have mouse models that allow specific and homogeneous expression of genes of interest in all BEC beds without concomitant expression in blood cells. Inducible Pdgfb-iCreERT2 and Cdh5(PAC)-CreERT2 transgenic mice are widely used for BEC targeting. However, issues remain in terms of recombination efficiency and specificity regarding hematopoietic cells. Objectives To determine which mouse model to choose when strong expression of a transgene is required in adult BECs from various organs, without concomitant expression in hematopoietic cells. Methods Using mT/mG reporter mice to measure recombination efficiency and conditional JAK2 mice to assess specificity regarding hematopoietic cells, we compared Pdgfb-iCreERT2 and Cdh5(PAC)-CreERT2 with well-characterized Tie2-Cre mice. Results Adult Cdh5(PAC)-CreERT2 mice are endothelial specific but require a dose of 10 mg of tamoxifen to allow constant Cre expression. Pdgfb-iCreERT2 mice injected with 5 mg of tamoxifen are appropriate for most endothelial research fields except liver studies, as hepatic sinusoid ECs are not recombined. Surprisingly, 2 months after induction of Cre-mediated recombination, all Pdgfb-iCreERT2;JAK2 mice developed a myeloproliferative neoplasm that is related to the presence of JAK2V617F in hematopoietic cells, showing for the first time that Cre-mediated recombination occurs in a small number of adult hematopoietic stem cells in Pdgfb-iCreERT2 transgenic mice. Conclusion This study provides useful guidelines for choosing the best mouse line to study the role of BECs in hemostasis and thrombosis

LPS-TLR4 Pathway mediates ductular cell expansion in alcoholic hepatitis.

Alcoholic hepatitis (AH) is the most severe form of alcoholic liver disease for which there are no effective therapies. Patients with AH show impaired hepatocyte proliferation, expansion of inefficient ductular cells and high lipopolysaccharide (LPS) levels. It is unknown whether LPS mediates ductular cell expansion. We performed transcriptome studies and identified keratin 23 (KRT23) as a new ductular cell marker. KRT23 expression correlated with mortality and LPS serum levels. LPS-TLR4 pathway role in ductular cell expansion was assessed in human and mouse progenitor cells, liver slices and liver injured TLR4 KO mice. In AH patients, ductular cell expansion correlated with portal hypertension and collagen expression. Functional studies in ductular cells showed that KRT23 regulates collagen expression. These results support a role for LPS-TLR4 pathway in promoting ductular reaction in AH. Maneuvers aimed at decreasing LPS serum levels in AH patients could have beneficial effects by preventing ductular reaction development