Evaluation of D-dimer and factor VIII in cirrhotic patients with asymptomatic portal venous thrombosis

D-dimers in advanced liver cirrhosis: Useful biomarker or not?

In clinical practice, the d-dimer levels rule out venous thromboembolism and diagnose disseminated intravascular coagulation. d-dimers increase in both physiological and pathological conditions. Liver cirrhosis, especially in the final stages, is characterized by complex coagulation and fibrinolysis factor disorders. Multiple mechanisms tried to explain the increased d-dimer levels in patients with liver cirrhosis and ascites. The d-dimer cut-off level used to rule out venous thromboembolism in cirrhosis is higher than that used to confirm the diagnosis of VTE or DIC in noncirrhotic patients. The cut-off d-dimer level used for the prognosis of thrombotic events is not standardized in advanced liver cirrhosis. Thus, it is necessary to update the clinical guidelines regarding the usefulness of d-dimer testing in advanced liver cirrhosis and the cut-off d-dimer levels, which should vary based on the detection method.

Effect of factor VIII and FVIII/PC ratio on portal vein thrombosis in liver cirrhosis: a systematic review and meta‑analysis

BACKGROUND

To date, there is an ongoing debate regarding the ability to predict PVT development using markers of FVIII or FVIII/PC ratio. This study presents evidence-based medical findings on the influence of FVIII activity levels and FVIII/PC values in the formation of PVT in cirrhosis.

METHODS

The search for original studies on risk factors for portal vein thrombosis (PVT) associated with cirrhosis was conducted, which primarily focused on comparing circulating FVIII activity levels or FVIII/PC ratio in cirrhotic patients with and without PVT. The quality of evidence from each study was assessed using the Newcastle-Ottawa Scale.

RESULTS

The meta-analysis included a total of 10 original studies. In total, 2250 cirrhotic patients were included, with 414 having PVT and 1836 without PVT. The pooled analysis using a random-effects model showed no significant difference in standardized mean difference (SMD) for FVIII activity levels in cirrhotic patients with or without PVT (SMD = 0.12, 95% CI=-0.46 to 0.70, P = 0.68), but there was significant heterogeneity (I2 = 95.52%, P = 0.00). Meta-regression analysis indicated that differences in mean FVIII activity levels in the PVT group, the number of cases in the non-PVT group, and the study design methods partially contributed to the heterogeneity (P < 0.05). However, compared to the non-PVT group, the PVT group had higher FVIII/PC ratio with a statistically significant difference (SMD = 0.39, 95% CI: 0.15 to 0.63, P = 0.00), and there was no significant heterogeneity (I2 = 28.62%).

CONCLUSION

In conclusion, the FVIII/PC ratio not only reflects the severity of liver disease, but also can be used as one of the predictors of PVT development.

Portal vein thrombosis in liver cirrhosis: An updated overview

Portal vein thrombosis (PVT) is a frequent and severe complication in patients with cirrhosis; however, the pathophysiology of PVT needs to be better clarified. There are few significant predictive factors in clinical practice, and the impact of PVT on cirrhosis progression and its complications, such as gastrointestinal bleeding, hepatic encephalopathy, and hepatorenal syndrome, remains uncertain. In recent years, the understanding of the mechanisms of PVT has become more profound with the publication of related literature. Therefore, in this review, we aim to summarize the advanced progress in the epidemiology, hazards, risk factors, diagnosis and classification, and treatment of PVT to provide insight into clinical management.

Potential utility of a multi-component coagulation factor panel to calculate MELD scores and assess the risk of portal vein thrombosis in chronic liver disease

BACKGROUND

Current quantitative approaches to assess chronic liver disease (CLD) severity have limitations. Further, portal vein thrombosis (PVT) pre-liver transplant (LT) is a major contributor to morbidity in CLD; the means of detecting and/or predicting PVT are limited. We sought to explore whether plasma coagulation factor activity levels can serve as a substitute for prothrombin time/international normalized ratio (PT/INR) in the Model for End-stage Liver Disease (MELD), and/or help assess the risk of PVT.

METHODS

Plasma activity levels of Factor V (FV), Factor VIII (FVIII), Protein C (PC), and Protein S (PS) and the concentrations of D-dimer, sP-selectin, and asTF were assessed in two cohorts of CLD patients (ambulatory, n = 42; LT, n = 43).

RESULTS

FV and PC activity levels strongly correlated with MELD scores, which enabled the development of a novel scoring system based on multiple linear regressions of the correlations of FV and PC activity with MELD-Na that substitutes PT/INR. Six-month and 1-year follow-up revealed that our novel approach was non-inferior to MELD-Na at predicting mortality. A significant inverse correlation between FVIII activity levels and PVT was found in the LT cohort (p = 0.010); FV and PS activity levels were in-trend (p = 0.069, p = 0.064). We developed a logistic regression-based compensation score to identify patients at risk of PVT.

CONCLUSIONS

We demonstrate that FV and PC activity levels may be used to replace PT/INR in MELD scoring. We also show the potential of using the combination of FV, FVIII, and PS activity levels to assess the risk of PVT in CLD.

Gut dysbiosis, endotoxemia and clotting activation: A dangerous trio for portal vein thrombosis in cirrhosis

Liver cirrhosis (LC) is associated with portal venous thrombosis (PVT) in roughly 20% of cirrhotic patients but the underlying mechanism is still unclear. Low-grade endotoxemia by lipopolysaccharides (LPS), a component of outer gut microbiota membrane, is detectable in the portal circulation of LC and could predispose to PVT. LPS may translocate into systemic circulation upon microbiota dysbiosis-induced gut barrier dysfunction, that is a prerequisite for enhanced gut permeability and ensuing endotoxemia. Experimental and clinical studies provided evidence that LPS behaves a pro-thrombotic molecule so promoting clotting and platelet activation. Experiments conducted in the portal circulation of cirrhotic patients showed the existence of LPS-related enhanced thrombin generation as well as endothelial dysfunction, venous stasis, and platelet activation. The review will analyze 1) the pro-thrombotic role of endotoxemia in the context of LC 2) the biological plausibility linking endotoxemia with PVT and 3) the potentially interventional tools to lower endotoxemia and eventually hypercoagulation.

Epidemiology of portal vein thrombosis in liver cirrhosis: A systematic review and meta-analysis

BACKGROUND

Portal vein thrombosis (PVT) may be associated with negative outcomes in patients with liver cirrhosis. However, the prevalence and incidence of PVT in liver cirrhosis are heterogeneous among studies and have not been sufficiently determined yet.

METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched. Eligible studies would explore the prevalence and/or incidence of PVT in liver cirrhosis without hepatocellular carcinoma or abdominal surgery. Pooled proportion with 95% confidence interval (CI) was calculated using a random-effect model. Factors associated with the presence/occurrence of PVT were also extracted.

RESULTS

Among the 8549 papers initially identified, 74 were included. Fifty-four studies explored the prevalence of PVT in liver cirrhosis with a pooled prevalence of 13.92% (95%CI=11.18-16.91%). Based on cross-sectional data, Child-Pugh class B/C, higher D-dimer, ascites, and use of non-selective beta-blockers (NSBBs) were associated with the presence of PVT in liver cirrhosis. Twenty-three studies explored the incidence of PVT in liver cirrhosis with a pooled incidence of 10.42% (95%CI=8.16-12.92%). Based on cohort data, Child-Pugh class B/C, higher model of end-stage liver disease score, higher D-dimer, lower platelets count, decreased portal flow velocity, ascites, use of NSBBs, and moderate or high-risk esophageal varices could predict the occurrence of PVT in liver cirrhosis.

CONCLUSION

Approximately one seventh of cirrhotic patients have PVT, and one tenth will develop PVT. Progression of liver cirrhosis and portal hypertension seems to be in parallel with the risk of PVT. Prospective studies with detailed information about classification and extension of PVT in liver cirrhosis are needed.

Predictive value of elevated serum D‑dimer for short‑term prognosis in patients with HBV‑related acute‑on‑chronic liver failure

To study the predictive value of elevated serum D-dimer on short-term prognosis in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) and the correlation between serum D-dimer level and the clinical data of these patients, a single center retrospective study was conducted to collect the clinical data and 28 and 90-day survival rates of 201 patients. Logistic regression analysis and receiver operating characteristic curves were used to determine the factors affecting short-term prognosis. A Kaplan-Meier curve was used to compare the difference in survival rate between the two groups with elevated D-dimer and normal D-dimer levels. Correlation analysis was used to determine the correlation between serum D-dimer level and the clinical data of the patients. The results showed that international normalized ratio (INR) >2.3 and age >53 years were independent risk factors affecting the 28-day survival rate of the patients (P<0.05). INR >2.3, serum total bilirubin >358.2 µmol/l, age >49 years and elevated serum D-dimer (>550 ng/ml) were independent risk factors affecting the 90-day survival rate of the patients (P<0.05). There were significant differences in the 90-day survival rate and the survival time between the patients with elevated D-dimer and normal D-dimer levels (P<0.05). Serum D-dimer level was positively associated with age, combined spontaneous peritonitis, albumin, INR and the model for end-stage liver disease sodium (MELD-Na) scores, and negatively associated with male sex, red blood cell count, and serum sodium and fibrinogen levels. It was concluded that elevated serum D-dimer (>550 ng/ml) is an independent risk factor affecting the 90-day survival rate of patients with HBV-ACLF. The 90-day survival rate and the survival time of patients with HBV-ACLF and elevated D-dimer levels are significantly lower than those with normal D-dimer levels. Overall, serum D-dimer is associated the short-term prognosis of patients with HBV-ACLF, and the detection of serum D-dimer level at admission can help predict the short-term prognosis of patients with HBV-ACLF, especially the 90-day prognosis.

Recurrent acute portal vein thrombosis with severe abdominal infection after right hemihepatectomy in a patient with perihilar cholangiocarcinoma: A case report and literature review

Introduction and importance

Portal vein thrombosis (PVT) is a serious complication after hepatobiliary-pancreatic surgery. There have been few studies on recurrent PVT after hepatectomy for perihilar cholangiocarcinoma.

Case presentation

We report the case of a 66-year-old woman who was diagnosed with perihilar cholangiocarcinoma and treated with right hemihepatectomy. On the sixth day, the patient developed acute portal vein thrombosis, and emergency portal vein incision and surgical thrombectomy were performed. On the seventh day after thrombectomy, the patient developed acute portal vein thrombosis again, and portal vein thrombectomy+portal vein bridging was performed again. There was still thrombosis after the operation. The patient was then treated with superior mesenteric arteriography + indirect portal vein catheterization thrombolysis and local thrombolysis + anticoagulation and systemic anticoagulation therapy. The patient had a complicated abdominal infection. The total hospital stay was 84 days. There was no thrombosis in the portal vein at discharge.

Clinical discussion

Although the procedure was carefully performed with a preoperative plan and fine intraoperative vascular anastomosis, postoperative PVT occurred. There are many factors of portal vein thrombosis, and there are many treatment methods.

Conclusion

PVT often develops in patients with liver cirrhosis postoperatively and after liver transplantation. Recurrent PVT after hepatectomy for perihilar cholangiocarcinoma is a rare complication.

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Recurrent PVT after hepatectomy for perihilar cholangiocarcinoma is rare.

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Artificial blood vessels can avoid portal vein angulation.

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Surgery combined with interventional therapy and drug therapy are available.

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The final outcome of the patient is usually good.

The Pathophysiology of Portal Vein Thrombosis in Cirrhosis: Getting Deeper into Virchow's Triad

Portal vein thrombosis (PVT) is a common complication among patients with cirrhosis. However, its pathophysiology is not well established and there are currently very few predictive factors, none of which are actually useful, from a clinical perspective. The contribution of each of the vertices of Virchow’s triad, e.g., blood hypercoagulability, blood flow, and portal vein endothelial damage in the development of PVT is not clear. In this review, we aim to recapitulate the latest studies on the field of PVT development in order to understand its mechanisms and discuss some of the future directions in the study of this important complication of cirrhosis.

Diagnostic accuracy of D-dimer in patients at high-risk for splanchnic vein thrombosis: A systematic review and meta-analysis

BACKGROUND

D-dimer is included in the diagnostic algorithm for deep vein thrombosis and pulmonary embolism. However, its role in the diagnosis of splanchnic vein thrombosis (SVT) is still controversial. The aim of this study was to evaluate the diagnostic accuracy of D-dimer for SVT.

METHODS

We performed a systematic review of the literature with meta-analysis (PROSPERO protocol registration number: CRD42020184300). The electronic databases MEDLINE, EMBASE, and CENTRAL were searched from inception to March 2021 week 4. Studies which evaluated D-dimer accuracy for SVT in any category of patients were selected. The index test was any D-dimer assay; the reference standard was any radiological imaging. The QUADAS-2 checklist was used for the risk of bias assessment. A bivariate random-effects regression model was used to calculate summary estimates of sensitivity and specificity.

RESULTS

12 studies (with a total of 1298 patients) evaluating the accuracy of D-dimer in patients at high risk of SVT (surgical patients, patients with liver cirrhosis or hepatocellular carcinoma) were included. None of the included studies was at low risk of bias. The weighted mean prevalence of SVT was 33.4% (95% CI, 22.5-45.2%, I2 = 94.8%). D-dimer accuracy was expressed by sensitivity 96% (95% CI, 72-100%); specificity 25% (95% CI, 5-67%); positive likelihood ratio 1.3 (95% CI, 0.9-1.9); negative likelihood ratio 0.16 (95% CI, 0.03-0.84); area under the ROC curve 0.80 (95% CI, 0.76-0.83).

CONCLUSIONS

D-dimer seems to have high sensitivity in the diagnosis of patients at high-risk for SVT. However, there is a strong need for more robust evidence on this topic.

Evaluation of Coagulation, Fibrinolysis and Endothelial Biomarkers in Cirrhotic Patients With or Without Portal Venous Thrombosis

To evaluate variations in coagulation, fibrinolysis and endothelial marker expression in cirrhotic patients and to explore their clinical value and predictive performance in cirrhotic patients with or without portal vein thrombosis (PVT), we performed a case-control study with 175 cirrhotic patients and 50 healthy individuals. 99 patients had PVT and another 76 patients did not. All participants were evaluated for plasma levels of conventional hemostatic markers. Thrombin-antithrombin complex (TAT), plasmin-α2-plasmin inhibitor complex (PIC), thrombomodulin (TM), tissue plasminogen activator inhibitor complex (t-PAIC), von Willebrand factor antigen (vWF: Ag) and coagulation factor Ⅷ (FⅧ: c) were also assessed and the ratio of TAT/t-PAIC was calculated. We analyzed differences in these biomarkers among the three groups and constructed receiver operating characteristic (ROC) curves. Patients with PVT exhibited significantly higher TAT and TAT/t-PAIC than cirrhotic patients without PVT (both P < 0.001). Areas under the curve (AUC) of ROC analyses for TAT and TAT/t-PAIC were 0.68 and 0.66, the cut-off levels were 1.55 ng/ml and 0.46, with sensitivities and specificities of 78.79% and 51.32% regarding TAT, 39.8% and 90.79% regarding TAT/t-PAIC. Levels of FⅧ: c and vWF: Ag in patients with PVT were significantly lower than those without PVT (p = 0.026 and p = 0.027, respectively). The AUC^ROC, cut-off level, sensitivity and specificity of FⅧ: c were 0.64, 111.1%, 66.67% and 60%, respectively. For vWF: Ag they were 0.61, 429%, 89.66% and 38.71%, respectively. Cirrhotic patients have disorders of coagulation, fibrinolysis and the endothelial system. TAT, TAT/t-PAIC, FⅧ: c and vWF: Ag can be used as potential biomarkers for predicting PVT in cirrhotic patients.

Exploring the Complex Role of Coagulation Factor VIII in Chronic Liver Disease

Chronic liver disease is one of the leading causes of death in the United States. Coagulopathy is often a sequela of chronic liver disease, however, the role and regulation of coagulation components in chronic liver injury remain poorly understood. Clinical and experimental evidence indicate that misexpression of the procoagulant factor VIII (FVIII) is associated with chronic liver disease. Nevertheless, the molecular mechanism of FVIII-induced chronic liver injury progression remains unknown. This review provides evidence supporting a pathologic role for FVIII in the development of chronic liver disease using both experimental and clinical models.

The risk factors of portal vein thrombosis in patients with liver cirrhosis

This study was designed to identify and assess risk factors for portal vein thrombosis (PVT) in patients with cirrhosis. A total of 98 cirrhosis patients with PVT were identified and 101 cirrhosis patients without PVT were chosen as the control group in this retrospective study. Several variables were measured and the two groups PVT and non-PVT were compared statistically. PVT was identified in 98 patients (10%). Significant differences in hematocrit, international normalized ratio, albumin, bilirubin and glucose were determined between the groups (P<0.05). Out of the thrombophilic risk factors in the patients with PVT factor V Leiden was identified in 8.8%, prothrombin gene 6.6% and methylenetetrahydrofolate reductase 2.2%. There was no difference in survival time between groups (P>0.05).

Portal vein thrombosis in cirrhosis: diagnosis, natural history, and therapeutic challenges

Portal vein thrombosis (PVT) is a frequent complication in cirrhosis and its prevalence increases with disease severity. Several factors are involved in the development and progression of PVT. The challenge for the management of PVT is the precise evaluation of the bleeding risk as opposed to life-threatening extension of thrombosis. Nevertheless, the impact on the progression and outcome of liver disease is unclear. A critical evaluation of the available data discloses that treating PVT in cirrhotics is safe and effective. However, there are open issues, such as which anticoagulant could represent a safer therapeutic option, and when and for how long this treatment should be administered to cirrhotic patients with PVT.

Gut-derived endotoxin stimulates factor VIII secretion from endothelial cells. Implications for hypercoagulability in cirrhosis

BACKGROUND & AIMS

Patients with cirrhosis display enhanced blood levels of factor VIII, which may result in harmful activation of the clotting system; however, the underlying mechanism is unknown.

METHODS

We performed a cross-sectional study in patients with cirrhosis (n=61) and matched controls (n=61) comparing blood levels of factor VIII, von Willebrand factor (vWf), lipopolysaccharide (LPS) and positivity for Escherichia coli DNA. Furthermore, we performed an in vitro study to investigate if LPS, in a concentration range similar to that found in the peripheral circulation of cirrhotic patients, was able to elicit factor VIII secretion from human umbilical vein endothelial cells (HUVEC).

RESULTS

Patients with cirrhosis displayed higher serum levels of LPS (55.8 [42.2-79.9] vs. 23.0 [7.0-34.0]pg/ml, p<0.001), factor VIII (172.0 [130.0-278.0] vs. 39.0 [26.0-47.0]U/dl, p<0.0001), vWf (265.0 [185.0-366.0] vs. 57.0 [48.0-65.0]U/dl, p<0.001) and positivity for Escherichia coli DNA (88% vs. 3%, p<0.001, n=34) compared to controls. Serum LPS correlated significantly with factor VIII (r=0.80, p<0.001) and vWf (r=0.63, p<0.001). Only LPS (beta-coefficient=0.70, p<0.0001) independently predicted factor VIII levels. The in vitro study showed that LPS provoked factor VIII and vWf release from HUVEC via formation and secretion of Weibel-Palade bodies, a phenomenon blunted by pre-treating HUVEC with an inhibitor of Toll-like receptor 4.

CONCLUSIONS

The study provides the first evidence that LPS derived from gut microbiota increases the systemic levels of factor VIII via stimulating its release by endothelial cells. Lay summary: Cirrhosis is associated with thrombosis in portal and systemic circulation. Enhanced levels of factor VIII have been suggested to play a role but the underlying mechanism is still unclear. Here we show that patients with cirrhosis display a concomitant increase of factor VIII and lipopolysaccharide (LPS) from Escherichia coli and suggest that LPS contributes to the release of factor VIII from endothelial cells.

Prevalence and outcome of portal thrombosis in a cohort of cirrhotic patients undergoing liver transplantation

INTRODUCTION

The prevalence of portal vein thrombosis (PVT) in patients that have undergone liver transplantation (LT) is 9.7% (SD 4.5). The aim of our study was to determine the prevalence, assess the factors that are associated with PVT and clarify their association with prognosis in patients with liver cirrhosis (LC) and LT.

AIMS AND METHODS

From 2005 to 2014, laboratory, radiological and surgical data were collected from patients with LC in our center who had undergone LT for the first time.

RESULTS

One hundred and ninety-one patients were included. The mean age was 55 (SD 9), 75.4% of patients were male and 48.7% had HCV. The Child-Pugh scores were A/B/C 41.9%/35.9%/25.5% and the MELD score was 15 (SD 6). Previous decompensations were: ascites (61.4%), hepatic encephalopathy (34.4%), variceal bleeding (25.4%), hepatocellular carcinoma (48.9%) and spontaneous bacterial peritonitis (SPB) (14.3%). The mean post-transplant follow-up was 42 months (0-113). PVT was diagnosed at LT in 18 patients (9.4%). Six patients were previously diagnosed using imaging tests (33.3%): 2 patients (11.1%) by DU and 4 patients (22.2%) by CT scan. All patients with PVT had DU in a mean time of 6 months before LT (0-44) and 90 patients (47.1%) had a CT scan in a median time of 6 months before LT (0-45). PVT was significantly related to the presence of SBP (33.3% vs 12.6%; p = 0.02) and lower levels of albumin (3.1g/dl vs 3.4g/dl; p = 0.05). MELD was higher in patients with PVT (16.6 vs 14.9; p = 0.3). There were no significant differences with regard to the need for transfusion of blood components. Moreover, the surgery time was similar in both groups. PVT correlated with a higher mortality in the first 30 days (8.8% vs 16.7%; p = 0.2).

CONCLUSION

Prior history of SBP and lower levels of albumin were identified as factors associated with PVT. The pre-transplant diagnosis rate is very low and the presence of PVT may have implications for short-term mortality.

Techniques and long-term effects of transjugular intrahepatic portosystemic shunt on liver cirrhosis-related thrombotic total occlusion of main portal vein

Portal vein hypertension (PVH) in liver cirrhosis complicated with portal venous thrombosis (PVT) has been mainly treated with transjugular intrahepatic portosystemic shunt (TIPS). The clinical effects of TIPS have been confirmed, however, no large-scale studies have been focused on technical analyses and a long-term follow-up, especially on thrombotic total occlusion of main portal vein (MPV). To demonstrate critical techniques and clinical outcome of TIPS on liver cirrhosis-related thrombotic total occlusion of MPV, 98 patients diagnosed with liver cirrhosis related thrombotic total occlusion of MPV and treated with TIPS from January 2000 to January 2010 were retrospectively analyzed. Twenty-three (23.5%) patients had MPV (single site) thrombosis, 55 (56.1%) had multiple site-thrombosis (MPV and other), 17 (17.3%) had cavernous transformation of portal vein, and 3 (3.1%) had post-transplant thrombosis. The successful rate of TIPS was 90.7%, without any procedure-related deaths or severe complications. Mean portal pressure was dropped from 33.08 ± 1.38 mmHg preoperatively to 20.18 ± 0.83 mmHg postoperatively (p < 0.001). Collectively, TIPS is safe and effective in treating liver cirrhosis-related thrombotic total occlusion of MPV. This complex procedure requires combination of indirect portography and percutaneous transhepatic portal techniques to increase the rate of success.

Coagulopathy Before and After Liver Transplantation: From the Hepatic to the Systemic Circulatory Systems

The hemostatic environment in patients with cirrhosis is a delicate balance between prohemostatic and antihemostatic factors. There is a lack of effective laboratory measures of the hemostatic system in patients with cirrhosis. Many are predisposed to pulmonary embolus, deep vein thrombosis, and portal vein thrombosis in the pretransplantation setting. This pretransplantation hypercoagulable milieu seems to extend for at least several months post-transplantation. Patients with nonalcoholic fatty liver disease, inherited thrombophilia, portal hypertension in the absence of cirrhosis, and hepatocellular carcinoma often require individualized approach to anticoagulation. Early reports suggest a potential role for low-molecular-weight heparins and direct-acting anticoagulants.

Portal vein thrombosis relevance on liver cirrhosis: Italian Venous Thrombotic Events Registry

Portal vein thrombosis may occur in cirrhosis; nevertheless, its prevalence, and predictors are still elusive. To investigate this issue, the Italian Society of Internal Medicine undertook the "Portal vein thrombosis Relevance On Liver cirrhosis: Italian Venous thrombotic Events Registry" (PRO-LIVER). This prospective multicenter study includes consecutive cirrhotic patients undergoing Doppler ultrasound examination of the portal area to evaluate the prevalence and incidence of portal vein thrombosis over a 2-year scheduled follow-up. Seven hundred and fifty-three (68 % men; 64 ± 12 years) patients were included in the present analysis. Fifty percent of the cases were cirrhotic outpatients. Viral (44 %) etiology was predominant. Around half of the patients had a mild-severity disease according to the Child-Pugh score; hepatocellular carcinoma was present in 20 %. The prevalence of ultrasound-detected portal vein thrombosis was 17 % (n = 126); it was asymptomatic in 43 % of the cases. Notably, more than half of the portal vein thrombosis patients (n = 81) were not treated with anticoagulant therapy. Logistic step-forward multivariate analysis demonstrated that previous portal vein thrombosis (p < 0.001), Child-Pugh Class B + C (p < 0.001), hepatocellular carcinoma (p = 0.01), previous upper gastrointestinal bleeding (p = 0.030) and older age (p = 0.012) were independently associated with portal vein thrombosis. Portal vein thrombosis is a frequent complication of cirrhosis, particularly in patients with moderate-severe liver failure. The apparent undertreatment of patients with portal vein thrombosis is a matter of concern and debate, which should be addressed by planning interventional trials especially with newer oral anticoagulants. Clinicaltrials.gov identifier NCT01470547.

Incidence and clinical presentation of portal vein thrombosis in cirrhotic patients

BACKGROUND

Portal vein thrombosis (PVT) is due to many risk factors, but its pathogenesis is still not clearly understood. To identify the risk factors for PVT, we analyzed the clinical characteristics and complications associated with PVT in cirrhotic patients.

METHODS

We studied patients with liver cirrhosis who were admitted to our unit from April 2009 to December 2014. The patients were divided into the PVT and non-PVT groups, and were compared by variables including gender, age, the etiology of cirrhosis, stage of cirrhosis, complications, imaging, and treatment.

RESULTS

PVT was found in 45 (9.8%) of 461 cirrhotic patients admitted to our hospital. Most patients (45.9%) had hepatitis B virus (HBV)-related cirrhosis, with a similar distribution of etiologies between the groups. However, there was no positive relationship between PVT and etiologies of cirrhosis. Most patients (71.5%) were in the stage of hepatic decompensation. No statistically significant differences were found in complications including esophageal varices, ascites, and hepatic encephalopathy between the groups. However, there was a significant positive correlation between hepatocellular carcinoma (HCC) and PVT (P<0.01). In 30 patients with PVT, thrombosis occurred in the portal vein and/or portal branches, 37.8% were diagnosed on ultrasound.

CONCLUSIONS

The incidence of PVT was 9.8%, mainly in patients with HBV-related cirrhosis. The development of PVT was associated with the severity of liver disease and HCC.

Hemostatic balance in patients with liver cirrhosis: Report of a consensus conference

Patients with cirrhosis present with hemostatic alterations secondary to reduced availability of pro-coagulant and anti-coagulant factors. The net effect of these changes is a rebalanced hemostatic system. The Italian Association of the Study of the Liver (AISF) and the Italian Society of Internal Medicine (SIMI) promoted a consensus conference on the hemostatic balance in patients with cirrhosis. The consensus process started with the review of the literature by a scientific board of experts and ended with a formal consensus meeting in Rome in December 2014. The statements were graded according to quality of evidence and strength of recommendations, and approved by an independent jury. The statements presented here highlight strengths and weaknesses of current laboratory tests to assess bleeding and thrombotic risk in cirrhotic patients, the pathophysiology of hemostatic perturbations in this condition, and outline the optimal management of bleeding and thrombosis in patients with liver cirrhosis.

Pre-transplant portal vein thrombosis is an independent risk factor for graft loss due to hepatic artery thrombosis in liver transplant recipients

BACKGROUND

Hepatic artery thrombosis is an uncommon but catastrophic complication following liver transplantation. We hypothesize that recipients with portal vein thrombosis are at increased risk.

METHODS

Data on all liver transplants in the U.S. during the MELD era through September 2014 were obtained from UNOS. Status one, multivisceral, living donor, re-transplants, pediatric recipients and donation after cardiac death were excluded. Logistic regression models were constructed for hepatic artery thrombosis with resultant graft loss within 90 days of transplantation.

RESULTS

63,182 recipients underwent transplantation; 662 (1.1%) recipients had early hepatic artery thrombosis; of those, 91 (13.8%) had pre-transplant portal vein thrombosis, versus 7.5% with portal vein thrombosis but no hepatic artery thrombosis (p < 0.0001). Portal vein thrombosis was associated with an increased independent risk of hepatic artery thrombosis (OR 2.17, 95% CI 1.71-2.76, p < 0.001) as was donor risk index (OR 2.02, 95% CI 1.65-2.48, p < 0.001). Heparin use at cross clamp, INR, and male donors were all significantly associated with lower risk.

DISCUSSION

Pre-transplant portal vein thrombosis is associated with post-transplant hepatic artery thrombosis independent of other factors. Recipients with portal vein thrombosis might benefit from aggressive coagulation management and careful donor selection. More research is needed to determine causal mechanism.

Spontaneous bleeding or thrombosis in cirrhosis: What should be feared the most?

The more modern and accurate concept of a rebalanced hemostatic status in cirrhosis is slowly replacing the traditional belief of patients with cirrhosis being "auto-anticoagulated", prone only to bleeding complications, and protected from thrombotic events. With greater attention to clinical thrombotic events, their impact on the natural history of cirrhosis, and with the emergence and increased use of point-of-care and global assays, it is now understood that cirrhosis results in profound hemostatic alterations that can lead to thrombosis as well as to bleeding complications. Although many clinical decisions are still based on traditional coagulation parameters such as prothrombin (PT), PT, and international normalized ratio, it is increasingly recognized that these tests do not adequately predict the risk of bleeding, nor they should guide pre-emptive interventions. Moreover, altered coagulation tests should not be considered as a contraindication to the use of anticoagulation, although this therapeutic or prophylactic approach is not at present routinely undertaken. Gastroesophageal variceal bleeding continues to be one of the most feared and deadly complications of cirrhosis and portal hypertension, but great progresses have been made in prevention and treatment strategies. Other bleeding sites that are frequently part of end-stage liver disease are similar to clinical manifestations of thrombocytopenia, with gum bleeding and epistaxis being very common but fortunately only rarely a cause of life-threatening bleeding. On the contrary, manifestations of coagulation factor deficiencies like soft tissue bleeding and hemartrosis are rare in patients with cirrhosis. As far as thrombotic complications are concerned, portal vein thrombosis is the most common event in patients with cirrhosis, but venous thromboembolism is not infrequent, and results in important morbidity and mortality in patients with cirrhosis, especially those with decompensated disease. Future studies and the more widespread use of point-of-care tests in evaluating hemostasis will aid the clinician in decision making when facing the patient with bleeding or with thrombotic complications, with both ends of a continuum being potentially fatal.

Procoagulant imbalance aggravated with falling liver function reserve, but not associated with the presence of portal vein thrombosis in cirrhosis

OBJECTIVES

Hypercoagulability, hemodynamic changes, and endothelial injury are the three major contributors to the development of thrombosis. However, the role of hypercoagulability in portal vein thrombosis (PVT) in liver cirrhosis is still controversial. The aim of this study is to elucidate the relationship between procoagulant imbalance and PVT in patients with liver cirrhosis.

METHODS

This study included 151 patients with cirrhosis with (n=20) or without PVT (n=131). Levels of procoagulant factor (FVIII) and anticoagulants [protein C (PC), protein S (PS), and antithrombin (AT)] were measured. Procoagulant imbalance was also evaluated using a thrombin generation test with/without Protac and the results were expressed as Protac-induced coagulation inhibition percentage (PICI%). The lower the PICI% value, the greater the procoagulant imbalance.

RESULTS

The levels of PC (P<0.001), PS (P<0.05), and AT (P<0.001) decreased progressively from Child-Pugh A to C in all patients, whereas the levels of FVIII did not alter with the severity of cirrhosis (P>0.05), which indicated the balance tilting toward procoagulation in liver cirrhosis. Similarly, the PICI% values decreased from Child-Pugh A to C (P<0.001). However, there were no differences in the levels of PC, PS, AT, FVIII or PICI% between patients with and without PVT (P>0.05), even after stratification by Child-Pugh classification (P>0.05).

CONCLUSION

Procoagulant imbalance is not associated with the presence of PVT in patients with cirrhosis, although the imbalance worsens with the severity of cirrhosis.

Role of D-dimer in the Development of Portal Vein Thrombosis in Liver Cirrhosis: A Meta-analysis

BACKGROUND AND AIMS

A meta-analysis was performed to explore the role of the D-dimer in the development of portal vein thrombosis (PVT) in liver cirrhosis.

METHODS

All papers were searched via PubMed, EMBASE, China National Knowledge Infrastructure, Wan Fang, and VIP databases. A standardized mean difference (SMD) with 95% confidence interval (CI) was pooled.

RESULTS

Overall, 284 studies were initially identified, of which 21 were included. Cirrhotic patients with PVT had a significantly higher D-dimer concentration than those without PVT (pooled SMD = 1.249, 95%CI = 0.740-1.758). After the portal hypertension-related surgery, cirrhotic patients with PVT had a similar preoperative D-dimer concentration to those without PVT (pooled SMD = 0.820, 95%CI = -0.122-0.286), but a higher postoperative value of D-dimer concentration than those without PVT (pooled SMD = 2.505, 95%CI = 0.975-4.036). Notably, the D-dimer concentration at the 1 st postoperative day was similar between cirrhotic patients with and without PVT (pooled SMD = 0.137, 95%CI = -0.827-1.101), but that at the 7 th post-operative day was higher in cirrhotic patients with PVT than in those without PVT (pooled SMD = 1.224, 95%CI = 0.277-2.171).

CONCLUSION

D-dimer might be regarded as a diagnostic marker for PVT in liver cirrhosis. In addition, postoperative D-dimer testing is worthwhile for the diagnosis of PVT after portal hypertension-related surgery.

Review article: portal vein obstruction--epidemiology, pathogenesis, natural history, prognosis and treatment

BACKGROUND

Portal vein obstruction may be due to portal vein thrombosis (PVT) or its sequale, the portal cavernoma. PVT is a common complication in liver cirrhosis, however, it may also occur as a primary vascular disorder, in absence of any liver disease.

AIM

To review the current knowledge on nomenclature, etiology, pathophysiology, clinical presentation, diagnostic workup and management of adult patients with obstruction in the portal vein, either as a primary vascular disease in adults, or as a complication of liver cirrhosis.

METHODS

A structured search in PubMed was performed using defined keywords (portal vein obstruction, extra-hepatic portal vein obstruction, PVT and portal cavernoma), including full text articles and abstracts in English language.

RESULTS

Several causes, operating both at local and systemic level, might play an important role in the pathogenesis of PVT. Frequently, more than one risk factor could be identified; however, occasionally no single factor is discernible. Diagnosis of portal vein obstruction depends on clinical presentation, imaging and laboratory investigations. Prompt treatment greatly affects the patient's outcome.

CONCLUSIONS

Portal vein obstruction occurring either due to thrombosis in the portal vein or due to the portal cavernoma, can contribute to significant morbidity and mortality in patients with or without cirrhosis. In recent years our understanding of etio-pathogenesis of portal vein obstruction has evolved tremendously, which has led to significant improvement in treatment outcomes. There are still areas where more studies are needed to better clarify the management issues of portal vein obstruction.

Portal vein thrombosis in cirrhosis

Portal vein thrombosis (PVT) is being increasingly recognized in patients with advanced cirrhosis and in those undergoing liver transplantation. Reduced flow in the portal vein is probably responsible for clotting in the spleno-porto-mesenteric venous system. There is also increasing evidence that hypercoagulability occurs in advanced liver disease and contributes to the risk of PVT. Ultrasound based studies have reported a prevalence of PVT in 10-25% of cirrhotic patients without hepatocellular carcinoma. Partial thrombosis of the portal vein is more common and may not have pathophysiological consequences. However, there is high risk of progression of partial PVT to complete PVT that may cause exacerbation of portal hypertension and progression of liver insufficiency. It is thus, essential to accurately diagnose and stage PVT in patients waiting for transplantation and consider anticoagulation therapy. Therapy with low molecular weight heparin and vitamin K antagonists has been shown to achieve complete and partial recanalization in 33-45% and 15-35% of cases respectively. There are however, no guidelines to help determine the dose and therapeutic efficacy of anticoagulation in patients with cirrhosis. Anticoagulation therapy related bleeding is the most feared complication but it appears that the risk of variceal bleeding is more likely to be dependent on portal pressure rather than solely related to coagulation status. TIPS has also been reported to restore patency of the portal vein. Patients with complete PVT currently do not form an absolute contraindication for liver transplantation. Thrombectomy or thromboendovenectomy is possible in more than 75% of patients followed by anatomical end-to-end portal anastomosis. When patency of the portal vein and/or superior mesenteric vein is not achieved, only non-anatomical techniques (reno-portal anastomosis or cavo-portal hemitransposition) can be performed. These techniques, which do not fully reverse portal hypertension, are associated with higher morbidity and mortality risks in the short term.

D-dimer as an early marker of severity in patients with acute superior mesenteric venous thrombosis

No early serum marker of disease severity contributes to the treatment decision-making process of acute superior mesenteric venous thrombosis (ASMVT). This study aims to assess the value of serum D-dimer level in the first 3 days after admission as a severity marker of ASMVT patients. From May 2010 to June 2014, 50 consecutive patients of ASMVT were enrolled in this observational study. The serum D-dimer level was measured on a daily basis during the first 3 days after admission as well as other laboratory-testing parameters, clinical score, and outcome variables recorded during the same period. The maximum and mean D-dimer values were analyzed and compared with other potential markers for prediction of multiple-organ dysfunction syndrome (MODS) and short-bowel syndrome (SBS). The correlation of D-dimer level with other potential severity markers and inflammation parameters were also studied. Both maximum and mean D-dimer level during the first 3 days of admission were significantly higher in patients with several clinical variables such as death within 30 days, bowel resection, sepsis, abdominal compartment syndrome, MODS, and SBS. In addition, serum D-dimer level showed precise prediction for MODS and SBS, greater than L-lactate and intestinal-type fatty acid-binding protein (I-FABP). The D-dimer level was correlated well with L-lactate, I-FABP, and APACHE II score on the first 3 days of admission. Poor correlation of D-dimer level and inflammation parameters, white blood cell count, and C-reactive protein level, was detected. D-dimer level could be an effective, early, and specific serum marker indicating the clinical evolution and outcome of ASMVT.

Is there a rationale for treatment of chronic liver disease with antithrombotic therapy?

Recent advances in the understanding of the coagulopathy in chronic liver disease have provided a strong support for anticoagulation as a new therapeutic paradigm for patients with cirrhosis. Laboratory studies indicate that the net effect of changes in hemostasis in many patients with chronic liver disease is a hypercoagulable status. In turn, clinical thrombosis is increasingly recognized as a complication of liver disease. When occurring within the liver, thrombosis may even progress the disease course. Exciting preliminary data regarding the potential of low-molecular-weight heparin to slow down the progression of liver disease indicate that this class of drugs may improve outcome without a major increase in bleeding risk. However, this new era for antithrombotic therapy in chronic liver disease is still hindered by a persistent false notion that patients with cirrhosis are "auto-anticoagulated" by their underlying liver disease. In addition, there is insufficient clinical evidence on safety and efficacy of anticoagulant therapy in cirrhosis and the studies conducted so far are limited by small sample sizes, uncontrolled treatment arms, or by their retrospective nature. Finally, a lack of knowledge on how or when to monitor antithrombotic treatment to optimize the risk-benefit ratio has restricted a widespread application of anticoagulant treatment in clinical management algorithms. Nonetheless, by systematically covering possibilities and pitfalls, this review highlights the potential of antithrombotic therapy to improve the quality of life and the clinical outcome of patients with chronic liver disease.

Association of hepatitis C with markers of hemostasis in HIV-infected and uninfected women in the women's interagency HIV study (WIHS)

BACKGROUND

Coinfection with HIV and hepatitis C virus (HCV) is common. HIV infection and treatment are associated with hypercoagulability; thrombosis in HCV is underinvestigated. Proposed markers of hemostasis in HIV include higher D-dimer, Factor VIII%, and plasminogen activator inhibitor-1 (PAI-1) antigen and lower total Protein S% (TPS) but have not been examined in HCV. We assessed the independent association of HCV with these 4 measures of hemostasis in a multicenter, prospective study of HIV: the Women's Interagency HIV Study.

METHODS

We randomly selected 450 HCV-infected (anti-HCV+ with detectable plasma HCV RNA) and 450 HCV-uninfected (anti-HCV-) women. HCV was the main exposure of interest in regression models.

RESULTS

Four hundred forty-three HCV+ and 425 HCV- women were included. HCV+ women had higher Factor VIII% (124.4% ± 3.9% vs. 101.8% ± 3.7%, P < 0.001) and lower TPS (75.7% ± 1.1% vs. 84.3% ± 1.1%, <0.001) than HCV- women, independent of HIV infection and viral load; there was little difference in PAI-1 or log10 D-dimer. After adjustment for confounders, these inferences remained. HIV infection was independently associated with higher Factor VIII% and log10 D-dimer and lower TPS.

CONCLUSIONS

HCV was independently associated with higher Factor VIII% and lower TPS consistent with hypercoagulability. Higher Factor VIII% and D-dimer and lower TPS were also strongly associated with HIV infection and levels of HIV viremia, independent of HCV infection. Further investigation is needed to determine if there is increased thrombotic risk from HCV. Studies examining hemostasis markers in HIV infection must also assess the contribution of HCV infection.

Coagulation imbalance may not contribute to the development of portal vein thrombosis in patients with cirrhosis

INTRODUCTION

The relationship between the imbalance in pro- and anti-coagulant factors and portal vein thrombosis (PVT) in individuals with cirrhosis is unclear. The aim of this study was to determine whether the imbalance in pro- and anti-coagulant factors contributes to the development of PVT in cirrhotic patients.

MATERIALS AND METHODS

Blood samples were collected from 30 consecutive cirrhotic patients with PVT and 30 age-, sex-, and Child-Pugh score-matched cirrhotic patients without PVT (controls), and the plasma levels of coagulation factors II, V, VII, VIII, IX, X, XI and XII and of protein C (PC), protein S (PS) and antithrombin (AT) were analyzed. The ratios of pro- vs. anti-coagulant factors were further investigated.

RESULTS

The levels of pro- and anti-coagulant factors were not statistically different between the PVT and control groups. Similar results were obtained when the patients were divided according to Child-Pugh classification. No difference was observed for the ratios of pro- vs. anti-coagulant factors between the two groups but the ratios of factor II-to-PC and factor VII-to-PC which were significantly decreased in the PVT group. Most of the ratios did not reach statistical significance in each Child-Pugh category except the followings: factor VIII-to-PS, factor XII-to-PC and factor XII-to-PS in class A patients; factor II-to-PS, factor VII-to-PC and factor VII-to-PS in class B patients. But the difference might not be so convincing.

CONCLUSIONS

PVT in cirrhotic patients may not result from coagulation imbalance.

Anticoagulation for the treatment of thrombotic complications in patients with cirrhosis

Cirrhotic patients can develop thrombotic complications, which in this group of patients occur with a greater frequency than in the general population. Portal vein thrombosis (PVT) is the most common thrombotic phenomenon, although deep venous thrombosis and pulmonary embolism can also occur. Risk factors for thrombosis include inherited and acquired deficiency of factors involved in anticoagulation mechanisms, venous stasis of the portal vein owing to architectural derangement of the liver and possibly local factors related to the endothelium. Clinical manifestations of PVT range from asymptomatic disease to a life-threatening complication, and although it is no longer considered an absolute contraindication for liver transplant, its presence may require challenging surgical techniques, which entail greater morbidity. Anticoagulation therapy is henceforth an important strategy to treat cirrhotic patients with PVT, although experience in this group of patients is limited. Vitamin K antagonists and low-molecular-weight heparin have been used successfully, achieving recanalization of the thrombosed vessel in patients with cirrhosis; however, the precise drug regimen management and monitoring has not be fully explored in this group of patients.

What we should know about portal vein thrombosis in cirrhotic patients: a changing perspective

Portal vein thrombosis (PVT) is one of the most common complications occurring during the natural course of liver cirrhosis. Even though PVT is often asymptomatic, the worsening of liver function, an unexpected episode of gastrointestinal bleeding or ascitic decompensation may be landmarks of PVT development. Beyond these clinical manifestations, it is debated whether PVT really has an impact on liver cirrhosis natural history or rather represents only one of its consequences. Probably PVT development should not only be considered as a matter of impaired blood flow or pro-coagulation tendency. On one hand, PVT seems a consequence of the worsening in portal vein outflow due to the increased hepatic resistance in cirrhotic livers. On the other hand, vascular microthrombosis secondary to necroinflammation may cause liver ischemia and infarction, with loss of hepatic tissue (parenchymal extinction) which is replaced by fibrotic tissue. Therefore, PVT might also be considered as the overt manifestation of the liver fibrosing process evolution and anticoagulant therapy may thus have microscopic indirect effects also on the progression of liver disease. At present, a connection between PVT development and the progression of liver fibrosis/cirrhosis has not yet been demonstrated. Nevertheless, it is not clear if PVT development may worsen cirrhotic patients' outcome by itself. Some authors tried to assess liver transplant benefit in PVT cirrhotic patients but data are contrasting. In this review, we will try to answer these questions, providing a critical analysis of data reported in literature.

Bleeding and thrombosis in cirrhotic patients: what really matters?

Bleeding complications, particularly in the gastro-intestinal tract, may complicate the clinical course of liver cirrhosis. Coexistence of abnormal global tests exploring the platelet and clotting systems generated the hypothesis that cirrhotic patients have "coagulopathy" predisposing to bleeding complications. Using more sophisticated laboratory methods this hypothesis has been partly confuted as cirrhotic patients actually disclose an ongoing prothrombotic state in the portal and systemic circulation that could predispose to thrombosis. Recent data of the literature support this hypothesis as portal vein thrombosis and peripheral thrombosis are frequent features of cirrhosis. We reviewed the literature data to assess the prevalence of bleeding and thrombotic complication in cirrhosis and the role of clotting activation in precipitating them. Whilst it appears scarcely relevant the interplay between the so called "coagulopathy" and bleeding, the interplay between clotting activation and thrombosis seems to be relevant but needs more accurate investigation in larger study populations.

Recombinant activated factor VII in liver patients: a retrospective cohort study from Australia and New Zealand

Recombinant factor VIIa (rFVIIa) is used in the treatment of life-threatening haemorrhage that is refractory to conventional treatment. The evidence supporting this practice in patients with liver disease is very limited. It has been used as a salvage therapy in end-stage liver disease (ESLD), in orthotopic liver transplant (OLT), other surgery, and upper gastrointestinal bleeding (UGIB) subpopulations. It has also been used prior to procedures in patients with ESLD. Data were collected by the Australia and New Zealand Haemostasis Registry (ANZHR) to perform a retrospective cohort study on the different subgroups of liver patients. This included 115 cases of use of rFVIIa in liver patients from 20 hospitals. A retrospective cohort study on the different subgroups of liver patients was performed. Main outcome measures were reduction or cessation of bleeding and 28-day mortality. Variables previously shown to predict response to bleeding after administration of rFVIIa were examined to determine whether correlations exist. Salvage therapy with rFVIIa was associated with reduction or cessation in bleeding in 24 of 36 OLT patients, 24 of 36 UGIB patients and 15 of 26 of other surgery patients. Clinical response to rFVIIa in OLT patients and other surgery patients was associated with a significantly lower mortality compared to nonresponders (P = 0.003 and 0.022, respectively). There was no relationship between mortality and bleeding response in patients with UGIB. Variables including acidosis, hypothermia, hypofibrinogenaemia, thrombocytopenia and Model of End-Stage Liver Disease (MELD) score were not associated with clinical response to rFVIIa. Five cases of use prior to procedures are described. Recombinant FVIIa is used as rescue therapy in surgical patients with ESLD and refractory haemorrhage in Australia and New Zealand. Traditional haemostasis variables were not associated with clinical response to rFVIIa in this cohort. Response to rFVIIa is associated with decreased mortality in ESLD patients undergoing OLT and other surgery, but not in UGIB.

The coagulopathy of chronic liver disease: is there a causal relationship with bleeding? Yes

Variceal hemorrhage is a major cause of death in patients with cirrhosis. Much still could be performed in clinical practice to reduce the risk for bleeding in cirrhotic patients and accurate predictive rules should be provided for early recognition of high-risk patients. Liver cirrhosis patients present a complex hemostatic dysfunction with prolongation of bleeding time, chronic coagulation activation, and secondary hyperfibrinolysis. Therefore, liver failure determines an acquired coagulopathy that has been considered to be one potential underlying mechanism of bleeding. Endotoxemia may play a pivotal role in activating clotting system in portal and systemic circulation and it could represent a common mechanism accounting for portal vein thrombosis, systemic hyperfibrinolysis and eventually gastrointestinal bleeding. Nevertheless, clinical trials should also be planned to investigate the causal relationship between acquired coagulopathy and bleeding in patients with chronic liver disease.

Systematic review: portal vein thrombosis in cirrhosis

BACKGROUND

As current imaging techniques in cirrhosis allow detection of asymptomatic portal vein thrombosis during routine ultrasonography, more patients with cirrhosis are diagnosed with portal vein thrombosis. Although a consensus on noncirrhotic extra-hepatic portal vein thrombosis has been published, no such consensus exists for portal vein thrombosis with cirrhosis.

AIM

To perform a systematic review of nonmalignant portal vein thrombosis in cirrhosis in terms of prevalence, pathogenesis, diagnosis, clinical course and management.

METHODS

Studies were identified by a search strategy using MEDLINE and EMBASE.

RESULTS

Portal vein thrombosis is encountered in 10-25% of cirrhotics. In terms of pathophysiology, cirrhosis is no longer considered a hypocoagulable state; rather than a bleeding risk in cirrhosis, various clinical studies support a thrombotic potential. Clinical findings of portal vein thrombosis in cirrhosis vary from asymptomatic disease to a life-threatening condition at first presentation. Optimal management of portal vein thrombosis in cirrhosis is currently not addressed in any consensus publication. Treatment strategies most often include the use of anticoagulation, while thrombectomy and transjugular intrahepatic portosystemic shunts are considered second-line options.

CONCLUSIONS

Portal vein thrombosis in cirrhosis has many unresolved issues, which are often the critical problems clinicians encounter in their everyday practice. We propose a possible research agenda to address these unresolved issues.

Viral cirrhosis: an overview of haemostatic alterations and clinical consequences

Viral hepatitis is a major health problem worldwide, the principal cause of cirrhosis and hepatocarcinoma. Once cirrhosis occurs, the consequences of liver dysfunction and portal hypertension become evident and, sometimes, life threatening for patients. Among the various complications of liver cirrhosis, the alteration of haemostatic balance is often a hard challenge for the clinician, since it is capable to predispose both to bleeding or thrombosis. In this review, we analyze the principal aspects of procoagulant, anticoagulant and fibrinolytic capacity of cirrhotic patients, which appears to be variably altered in all these aspects, not only in the direction of a tendency to bleeding. Laboratory investigations, at present, may provide only a partial representation of this condition, because of the impossibility to obtain a test capable to furnish a global overview of the haemostatic system and to reproduce in vivo conditions. Furthermore, we describe the pathophysiological mechanisms underlying bleeding manifestations and thrombosis development in cirrhotic patients, which should be considered not only as obvious consequences of the advanced liver disease but, rather, as the result of a complex interaction between inherited and acquired factors.

High levels of factor VIII and risk of extra-hepatic portal vein obstruction

BACKGROUND/AIMS

High levels of coagulation factor VIII are a risk factor for lower-limb deep vein thrombosis (DVT). Their role in extra-hepatic portal vein obstruction (EHPVO) is not established.

METHODS

Factor VIII was measured in 85 patients with EHPVO (primary in 58 and complicating liver cirrhosis in 27), in 200 with lower-limb DVT, in 108 with liver cirrhosis without thrombosis and in 200 healthy controls.

RESULTS

Factor VIII levels were significantly higher in patients with primary EHPVO (138 IU/dL, range 86-366), EHPVO and cirrhosis (147 IU/dL, 95-242), lower-limb DVT (140 IU/dL, 64-400) and cirrhosis alone (160 IU/dL, 43-446) than in controls (112 IU/dL, 62-250, p<0.001). When factor VIII exceeded 129 IU/dL (66th percentile), the odds ratios were 10.5 (95%CI 3.3-33.4) for primary EHPVO, 6.0 (1.2-30.7) for EHPVO and cirrhosis, 5.0 (2.6-9.4) for lower-limb DVT. After exclusion of the effect of the acute phase reaction, the odds ratio for primary EHPVO was 4.2 (0.8-22.7), and was 8.7 (0.9-80.5) after exclusion also of patients with chronic myeloproliferative disorders.

CONCLUSIONS

High factor VIII levels are independently associated with an increased risk for EHPVO. The risk of EHPVO increased with increasing factor VIII levels and was only partially dependent on the acute phase reaction.

Predictive value of D-dimer for portal vein thrombosis after portal hypertension surgery in hepatitis B virus-related cirrhosis

AIM

To evaluate the predictive value of D-dimer as a predictive indicator of portal vein thrombosis (PVT) after portal hypertension surgery in hepatitis B virus-related cirrhosis.

METHODS

A prospective study was carried out in 52 patients who had undergone surgery for portal hypertension in hepatitis B virus-related cirrhosis. Changes in perioperative dynamic D-dimer were observed. The sensitivity, specificity, positive predictive values and negative predictive values of D-dimer were calculated, and ROC curves were analyzed.

RESULTS

The D-dimer levels in the group developing postoperative PVT was significantly higher than those in the group not developing PVT (P = 0.001), and the ROC semiquantitative and qualitative analysis of D-dimer showed a moderate predictive value in PVT (semi-quantitative value Az = 0.794, P = 0.000; qualitative analysis: Az = 0.739, P = 0.001).

CONCLUSION

Dynamic monitoring of D-dimer levels in patients with portal hypertension after surgery can help early diagnosis of PVT, as in cases where the D-dimer levels steadily increase and exceed 16 microg/mL, the possibility of PVT is very high.

Portal vein thrombosis in liver cirrhosis

Portal vein thrombosis (PVT) is observed in 10-20% of patients with liver cirrhosis, which is responsible for 20% of all PVT cases. The main pathogenic factor of PVT in cirrhosis is the obstacle to portal flow, but acquired and inherited clotting abnormalities may play a role. The formation of collateral veins allows many patients to remain asymptomatic and prevents the onset of clinical complications also in patients with totally occlusive PVT. Gastrointestinal bleeding, thrombosis of superior mesenteric vein and refractory ascites are typical manifestations of PVT. Instrumental diagnosis can be obtained by colour-doppler ultrasonography. Future studies should verify whether asymptomatic PVT worsens liver failure, or if its life-threatening complications reduce survival in patients with cirrhosis. Moreover, randomized controlled trials should clarify the potential effectiveness of anticoagulant therapy in the treatment of PVT.

Predictive value of D-dimer for portal vein thrombosis after portal hypertension surgery in hepatitis B virus-related cirrhosis

AIM: To evaluate the predictive value of D-dimer as a predictive indicator of portal vein thrombosis (PVT) after portal hypertension surgery in hepatitis B virus-related cirrhosis.

METHODS: A prospective study was carried out in 52 patients who had undergone surgery for portal hypertension in hepatitis B virus-related cirrhosis. Changes in perioperative dynamic D-dimer were observed. The sensitivity, specificity, positive predictive values and negative predictive values of D-dimer were calculated, and ROC curves were analyzed.

RESULTS: The D-dimer levels in the group developing postoperative PVT was significantly higher than those in the group not developing PVT (P = 0.001), and the ROC semi-quantitative and qualitative analysis of D-dimer showed a moderate predictive value in PVT (semi-quantitative value Az = 0.794, P = 0.000; qualitative analysis: Az = 0.739, P = 0.001).

CONCLUSION: Dynamic monitoring of D-dimer levels in patients with portal hypertension after surgery can help early diagnosis of PVT, as in cases where the D-dimer levels steadily increase and exceed 16 μg/mL, the possibility of PVT is very high.

Are chronic hepatitis C viral infections more benign in patients with hemophilia?

BACKGROUND AND AIMS

Cirrhosis is associated with thromboses of the intrahepatic vasculature. This raises the possibility that HCV infections in hemophiliacs may differ from those in non-hemophiliacs

METHODS

Liver biopsy findings from 12 hemophiliacs and 20 age- and gender-matched, non-hemophiliac controls with chronic hepatitis C viral (HCV) infections were compared for inflammatory activity and fibrosis.

RESULTS

The mean ages of hemophiliacs and controls were 35.0 +/- 3.0 yr and 39.6 +/- 5.6 yr, respectively (P= 0.2). Serum aspartate aminotransferase (AST) levels were lower (44 +/- 13 vs 70 +/- 43 U/L) and the duration of the partial thromboplastin (PTT) time longer (49.2 +/- 16.9 vs 31.2 +/- 1.2 s.) in hemophiliacs than in controls (P < 0.02 and <0.001, respectively). Six of the seven hemophiliac patients (86%) and 8/17 controls (46%) were infected with genotypes 1a or 1b with the remainder being infected with 2b, 3a, or 3b. Histological activity and fibrosis scores were significantly lower in hemophiliacs than in controls (1.9 +/- 0.6 vs 3.6 +/- 2.7 and 0.3 +/- 0.2 vs 1.5 +/- 1.5, P < 0.05 and P < 0.01, respectively). None of the hemophiliacs had histological evidence of advanced disease (bridging fibrosis and/or cirrhosis) as compared to 7/20 (30%) controls (P < 0.05).

CONCLUSION

HCV infections in hemophiliacs may be less severe than in HCV infected patients without hemophilia.

Thrombosis of the portal venous system

Portal vein thrombosis (PVT) is a rare cause of portal hypertension. Its diagnosis has been facilitated by improvements in imaging techniques, in particular Doppler sonography. The prevalence is about 1% in the general population, but much higher rates are observed in patients with hepatic cirrhosis (7%, range 0.6-17%), particularly those who also have hepatocellular carcinoma (HCC) (35%). The most common causes of PVT are myeloproliferative disorders, deficiencies of anticoagulant proteins, prothrombotic gene mutations, cirrhosis with portal hypertension, and HCC. Its development often requires the presence of two or more risk factors (local and/or systemic), e.g., a genetically determined thrombophilic state plus an infectious episode or abdominal surgery. It is clinically useful to distinguish between cirrhotic and noncirrhotic forms. Portal vein thrombosis is also traditionally classified as acute or chronic, but this distinction is often difficult. Color Doppler ultrasound is the first-line imaging study for diagnosis of PVT; magnetic resonance angiography and CT angiography are valid alternatives. The main complications are ischemic intestinal necrosis (in acute PVT) and esophageal varices (in chronic cases); the natural history of the latter differs depending on whether or not the thrombosis is associated with cirrhosis. The treatment of choice for PVT has never been adequately investigated. It is currently based on the use of anticoagulants associated, in some cases, with thrombolytics, but experience with the latter agents is too limited to draw any definite conclusions. In chronic thrombosis (even forms associated with cirrhosis), anticoagulant therapy is recommended and possibly, beta-blockers as well. Naturally, treatment of the underlying pathology is essential.

A case of deep venous thrombosis associated with pegylated interferon alpha2b plus ribavirin treatment of chronic hepatitis C

We present a case of deep venous thrombosis (DVT) during pegylated interferon (peg-IFN)-alpha2b plus ribavirin treatment of chronic hepatitis C (CHC). A 67-year-old man, who had been under treatment for hypertension and diabetes mellitus, was admitted to our hospital for peg-IFN-alpha2b plus ribavirin treatment for CHC. His serum hepatitis C virus (HCV) RNA level became undetectable 1 week after the initiation of peg-IFN-alpha2b plus ribavirin treatment. He suffered from severe pain, flare, and edema in both of his lower legs 6 weeks after the initiation of peg-IFN-alpha2b plus ribavirin treatment. He was diagnosed as having DVT because of the presence of a thrombus in the right soleus vein by ultrasonography. Peg-IFN-alpha2b plus ribavirin treatment was discontinued because a causal relationship between DVT and peg-IFN-alpha2b plus ribavirin treatment was suspected. DVT was not observed and the symptoms in both of his legs were improved after the administration of warfarin potassium. Subsequently, DVT has not recurred, and he has remained HCV-RNA negative.