Increased platelet ratio in patients with decompensated cirrhosis indicates a higher risk of portal vein thrombosis

Reticulated platelets are increased and hyper-activated in patients with cirrhosis, especially those with poor outcome

BACKGROUND

Reticulated platelets (RePLT) are emergency circulating platelets released to contrast peripheral platelet destruction.

AIM

We conducted a prospective study to [a] characterize RePLT in cirrhosis; [b] evaluate the association between RePLT and hepatic decompensation/death.

METHODS

Cirrhosis patients without hepatocellular carcinoma were prospectively recruited and underwent assessment of RePLT and thrombopoietin (TPO). RePLT were evaluated by cytofluorimetry and immuno-fluorescence microscopy. Twenty healthy subjects were included as controls. Patients were followed for 6 months for hepatic decompensation and further decompensation/ACLF.

RESULTS

Forty-five patients were included (Child-Pugh [CP] A/B/C 18/11/16). Compared to controls, RePLT in cirrhosis were significantly increased (0.82% vs. 0.05%; p < 0.001) and hyperactivated (4.35% vs. 0.17%; p = 0.004). No correlation was observed between RePLT and CP, platelet count, TPO, MELD score, and C-reactive protein. TPO was lower in cirrhosis than controls (28 pg/mL vs. 52 pg/mL; p = 0.005), decreasing significantly with CP stage. In CP B/C patients (n = 27), RePLT were significantly higher in those who progressed towards further decompensation/ACLF (2.11 [0.56-2.95] vs. 0.69 [0.02-1.22]; p < 0.01). A proportion of RePLT >2% accurately identified high-risk patients (AUROC 0.818; 95%CI: 0.639-0.997; sensitivity 94%, specificity 73%).

CONCLUSION

RePLT in cirrhosis are increased and hyper-activated. In decompensated patients, higher RePLT appear to be associated with worse outcomes.

Profiling plasma alterations of extracellular vesicles in patients with acutely decompensated cirrhosis and bacterial infection

BACKGROUND

Extracellular vesicles (EVs) modulate inflammation, coagulation and vascular homeostasis in decompensated cirrhosis.

AIM

To characterize the profile of plasmatic EVs in patients with decompensated cirrhosis and bacterial infections and evaluate the association between EVs and the development of hemostatic complications.

METHODS

We measured the levels of EVs using high-sensitivity flow cytometry and phospholipid-dependent clotting time (PPL) in a prospective cohort of hospitalized patients with acutely decompensated cirrhosis with versus without bacterial infections. A separate cohort of patients with bacterial infections without cirrhosis was also enrolled. We measured endothelium-, tissue factor (TF)-bearing, platelet- and leukocyte-derived EVs. In patients with infections, EVs were reassessed upon resolution of infection. Bleeding and thrombotic complications were recorded during 1-year follow-up.

RESULTS

Eighty patients with decompensated cirrhosis were recruited (40 each with and without bacterial infections). Electron microscopy confirmed the presence of plasma EVs. Despite no difference in total EVs and PPL, patients with cirrhosis and infection had significantly higher TF+ EVs, P-Selectin+ EVs (activated platelet-derived), CD14+ EVs (monocyte/macrophages derived) and CD14+ TF+ EVs versus those with cirrhosis without infection. Upon infection resolution, levels of these EVs returned to those without infection. Patients with infections showed a significant association between reduced P-Selectin+ EVs and bleeding complications (HR 8.0 [95%CI 1.3-48.1]), whereas high levels of leukocyte-derived EVs (CD45+) and CD14+ EVs were significantly associated with thrombotic complications (HR 16.4 [95%CI 1.7-160] and 10.9 [95%CI 1.13-106], respectively). Results were confirmed in a validation cohort.

CONCLUSION

Bacterial infections are associated with particular alterations of plasma EVs profile in decompensated cirrhosis. Bacterial infections trigger the release of EVs originating from various cell types, which may tip the precarious hemostatic balance of patients with acutely decompensated cirrhosis towards hyper- or hypocoagulability.

Portal Vein Thrombosis: State-of-the-Art Review

Background: Portal vein thrombosis (PVT) is a rare disease with an estimated incidence of 2 to 4 cases per 100,000 inhabitants. The most common predisposing conditions for PVT are chronic liver diseases (cirrhosis), primary or secondary hepatobiliary malignancy, major infectious or inflammatory abdominal disease, or myeloproliferative disorders. Methods: PVT can be classified on the basis of the anatomical site, the degree of venous occlusion, and the timing and type of presentation. The main differential diagnosis of PVT, both acute and chronic, is malignant portal vein invasion, most frequently by hepatocarcinoma, or constriction (typically by pancreatic cancer or cholangiocarcinoma). Results: The management of PVT is based on anticoagulation and the treatment of predisposing conditions. The aim of anticoagulation in acute thrombosis is to prevent the extension of the clot and enable the recanalization of the vein to avoid the development of complications, such as intestinal infarction and portal hypertension. Conclusions: The treatment with anticoagulant therapy favors the reduction of portal hypertension, and this allows for a decrease in the risk of bleeding, especially in patients with esophageal varices. The anticoagulant treatment is generally recommended for at least three to six months. Prosecution of anticoagulation is advised until recanalization or lifelong if the patient has an underlying permanent pro-coagulant condition that cannot be corrected or if there is thrombosis extending to the mesenteric veins.

The evolving knowledge on primary hemostasis in patients with cirrhosis: A comprehensive review

Patients with cirrhosis develop complex alterations in primary hemostasis that include both hypocoagulable and hypercoagulable features. This includes thrombocytopenia, multiple alterations of platelet function, and increased plasma levels of von Willebrand factor. Contrary to the historical view that platelet dysfunction in cirrhosis might be responsible for an increased bleeding tendency, the current theory posits a rebalanced hemostasis in patients with cirrhosis. Severe thrombocytopenia is not indicative of the bleeding risk in patients undergoing invasive procedures and does not dictate per se the need for pre-procedural prophylaxis. A more comprehensive and individualized risk assessment should combine hemostatic impairment, the severity of decompensation and systemic inflammation, and the presence of additional factors that may impair platelet function, such as acute kidney injury and bacterial infections. Although there are multiple, complex alterations of platelet function in cirrhosis, their net effect is not yet fully understood. More investigations evaluating the association between alterations of platelet function and bleeding/thrombosis may improve risk stratification in patients with decompensated cirrhosis. Besides hemostasis, the assessment of von Willebrand factor Ag and ADP-induced, whole-blood platelet aggregation normalized by platelet count (VITRO score and PLT ratio) are promising biomarkers to predict the risk of hepatic decompensation and survival in both compensated and decompensated patients. Further investigations into the in vivo interplay between platelets, circulating blood elements, and endothelial cells may help advance our understanding of cirrhotic coagulopathy. Here, we review the complex changes in platelets and primary hemostasis in cirrhosis and their potential clinical implications.

Decreased platelet activation predicts hepatic decompensation and mortality in patients with cirrhosis

BACKGROUND AND AIMS

Patients with cirrhosis show alterations in primary hemostasis, yet prognostic implications of changes in platelet activation remain controversial, and assay validity is often limited by thrombocytopenia. We aimed to study the prognostic role of platelet activation in cirrhosis, focusing on bleeding/thromboembolic events, decompensation, and mortality.

APPROACH AND RESULTS

We prospectively included 107 patients with cirrhosis undergoing a same-day hepatic venous pressure gradient (HVPG) and platelet activation measurement. Platelet activation was assessed using flow cytometry after protease-activated receptor (PAR)-1, PAR-4, or epinephrine stimulation. Over a follow-up of 25.3 (IQR: 15.7-31.2) months, first/further decompensation occurred in 29 patients and 17 died. More pronounced platelet activation was associated with an improved prognosis, even after adjusting for systemic inflammation, HVPG, and disease severity. Specifically, higher PAR-4-inducible platelet activation was independently linked to a lower decompensation risk [adjusted HR per 100 MFI (median fluorescence intensity): 0.95 (95% CI: 0.90-0.99); p =0.036] and higher PAR-1-inducible platelet activation was independently linked to longer survival [adjusted HR per 100 MFI: 0.93 (95% CI: 0.87-0.99); p =0.040]. Thromboembolic events occurred in eight patients (75% nontumoral portal vein thrombosis [PVT]). Higher epinephrine-inducible platelet activation was associated with an increased risk of thrombosis [HR per 10 MFI: 1.07 (95% CI: 1.02-1.12); p =0.007] and PVT [HR per 10 MFI: 1.08 (95% CI: 1.02-1.14); p =0.004]. In contrast, of the 11 major bleedings that occurred, 9 were portal hypertension related, and HVPG thus emerged as the primary risk factor.

CONCLUSIONS

Preserved PAR-1- and PAR-4-inducible platelet activation was linked to a lower risk of decompensation and death. In contrast, higher epinephrine-inducible platelet activation was a risk factor for thromboembolism and PVT.

Anticoagulant therapy for splanchnic vein thrombosis: recent updates for patients with liver cirrhosis

INTRODUCTION

Liver cirrhosis is accompanied by several hemostatic alterations, which contribute to the current theory of "rebalanced hemostasis." Splanchnic vein thrombosis (SVT) is a frequent complication of liver cirrhosis (17-26% of the cirrhotic patients), and liver cirrhosis is a common risk factor for SVT (24-28% of SVT cases).

AREAS COVERED

This narrative review aims to describe the current state of the art on the anticoagulant treatment of cirrhotic SVT, with a particular focus on the possible role of the direct oral anticoagulants (DOACs) and recent guidelines on this topic.

EXPERT OPINION

Early anticoagulant therapy is recommended in cirrhotic patients with acute SVT, to obtain vessel recanalization and decrease the rates of portal hypertension-related complications. Gastroesophageal varices do not represent a contraindication to anticoagulation, if adequate prophylaxis of variceal bleeding is established, and varices band ligation can be safely performed without the need to stop the anticoagulant treatment. The conventional treatment of cirrhotic SVT consisted of low molecular weight heparin, as initial treatment of choice, eventually followed by vitamin K antagonists, but the DOACs can be considered as a reasonable alternative in patients with compensated liver cirrhosis.

Portal Vein Thrombosis in the Setting of Cirrhosis: A Comprehensive Review

Portal vein thrombosis constitutes the most common thrombotic event in patients with cirrhosis, with increased rates in the setting of advanced liver disease. Despite being a well-known complication of cirrhosis, the contribution of portal vein thrombosis to hepatic decompensation and overall mortality is still a matter of debate. The incorporation of direct oral anticoagulants and new radiological techniques for portal vein recanalization have expanded our therapeutic arsenal. However, the lack of large prospective observational studies and randomized trials explain the heterogenous diagnostic and therapeutic recommendations of current guidelines. This article seeks to make a comprehensive review of the pathophysiology, clinical features, diagnosis, and treatment of portal vein thrombosis in patients with cirrhosis.