Plasma von Willebrand factor levels predict in-hospital survival in patients with acute-on-chronic liver failure

Definitions, Etiologies, and Outcomes of Acute on Chronic Liver Failure: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is a major public health concern. We aimed to assess the definitions, etiologic spectrum, organ failure (OF), and outcomes of ACLF globally.

METHODS

Three databases were searched for studies on ACLF from 1990 until September 2022. Information regarding definitions, acute precipitants, underlying chronic liver disease (CLD), OF, and mortality were extracted. Meta-analyses were performed for pooled prevalence rates (95% confidence interval [CI]) using random-effects model for each definition of ACLF.

RESULTS

Of the 11,451 studies identified, 114 articles (142 cohorts encompassing 210,239 patients) met the eligibility criteria. Most studies (53.2%) used the European Association for the Study of the Liver (EASL) definition, followed by Asia-Pacific Association for the Study of the Liver (APASL) (33.3%). Systemic infection was the major acute precipitant, and alcohol use was the major cause of CLD in EASL-defined studies, whereas alcohol was both the major acute precipitant and cause of CLD in APASL-defined studies. Liver failure was the major OF in APASL-based studies, whereas renal failure was predominant in EASL-based studies. Thirty-day mortality varied across definitions: APASL: 38.9%, 95% CI, 31.2%-46.9%; EASL: 47.9%, 95% CI, 42.2%-53.5%; and NACSELD: 52.2%, 95% CI, 51.9%-52.5%. Diagnostic overlap between definitions ranged from 7.7% to 80.2%. Meta-regression suggested that the World Health Organization region influenced 30-day mortality in studies using EASL definition.

CONCLUSIONS

Heterogeneity in the definition of ACLF proposed by different expert societies and regional preferences in its use result in differences in clinical phenotype and outcomes. A uniform definition would enhance the comparability and interpretation of global data.

Von Willebrand factor processing in patients with advanced chronic liver disease and its relation to portal hypertension and clinical outcome

BACKGROUND AND AIMS

Endothelial dysfunction and portal hypertension (PH) are reflected by increased von Willebrand factor antigen (VWF-Ag) levels in advanced chronic liver disease (ACLD). This study investigated VWF release and cleavage and their association with PH and clinical outcomes.

METHODS

Levels of VWF-Ag, VWF-N (VWF-propeptide), and VWF-A (VWF processed by the main VWF-cleaving protease ADAMTS13) were assessed in 229 patients with clinically stable ACLD (hepatic venous pressure gradient [HVPG] ≥ 6 mmHg; absence of bacterial infections or acute decompensation) undergoing HVPG-measurement. Liver-healthy individuals served as controls (n = 24).

RESULTS

VWF-Ag and VWF-N were similarly accurate for the identification of clinically significant PH (CSPH; HVPG ≥ 10 mmHg) in compensated ACLD (AUROC: VWF-Ag 0.748; VWF-N 0.728). ADAMTS13 activity was similar between patients with ACLD and controls and did not correlate with PH and disease severity, whereas VWF cleavage decreased in patients with CSPH (i.e., VWF-Ag/-A-ratio increased). In vitro VWF activity strongly reflected VWF-Ag levels (Spearman's r = 0.874, p < 0.001), but decreased (vs. controls) in patients with CSPH when normalized to VWF-Ag levels (VWF-activity/-Ag-ratio). VWF-Act/-Ag ratio correlated negatively with ADAMTS13 activity (r =- 0.256, p < 0.001). ADAMTS13 activity was independently predictive for (i) portal vein thrombosis (PVT) and (ii) hepatic decompensation or liver-related death.

CONCLUSIONS

VWF-Ag levels and its propeptide are similarly suitable surrogates of PH in patients with compensated ACLD. ADAMTS13-Act was not linked to disease and PH severity, however, when normalized to VWF-Ag, both VWF cleavage and VWF activity were decreased in patients with CSPH, as compared to liver-healthy individuals. Low ADAMTS13-Act was associated with presumably more procoagulant VWF and adverse outcomes.

CLINICAL TRIAL NUMBER

NCT03267615.

Von Willebrand factor is an independent predictor of short-term mortality in acutely ill patients with cirrhosis

BACKGROUND AND AIMS

Levels of von Willebrand factor (VWF) are elevated in patients with cirrhosis, and correlate well with disease severity. In patients with decompensated cirrhosis (DC), plasma VWF is associated with mortality. The value of VWF in predicting short-term mortality risk in patients with acute-on-chronic liver failure (ACLF) is, however, unclear.

METHODS

We included patients with DC (n = 111) and ACLF (n = 105). We measured VWF levels and correlated these with other laboratory parameters and prediction models for mortality. Also, we assessed the predictive value of VWF in the prediction of 90- and 30-day mortality in patients with DC and ACLF, respectively, and compared this to the predictive value of clinically used prediction models. Finally, we determined the optimal cut-off value for VWF in patients with ACLF.

RESULTS

Sixteen of 111 (14%) patients with DC and 35 of 105 (33%) with ACLF died within 90 and 30 days, respectively. VWF was associated with mortality and correlated closely with other prediction models. In patients with ACLF, VWF levels had a discrimination for 30-day mortality comparable with these models and accurately identified ACLF patients with high 30-day mortality risk.

CONCLUSIONS

Levels of VWF associate closely with risk of mortality in patients with DC and ACLF, and may have predictive utility as a laboratory marker of prognosis. Further research is warranted to assess the additional value of VWF in the prediction of mortality and associated complications in chronic liver failure syndromes.

Growing Evidence for Survival Benefit with Plasma Exchange to Treat Liver Failure

Plasma exchange (PLEX) to treat liver failure patients is gaining increasing momentum in recent years. Most reports have used PLEX to treat patients with acute liver failure (ALF) or acute on chronic liver failure (ACLF). Etiology of liver disease has an important bearing on the prognosis of the illness in these patients. The accruing data suggest survival benefit with PLEX compared with standard medical treatment to treat ALF and ACLF patients, in randomised controlled trials done world-over. The American College of Apheresis now recommends high-volume PLEX as first-line treatment for ALF patients. Most matched cohort studies done from India which recruited patients with a specific etiology of ALF or ACLF report survival benefit with PLEX compared to standard medical treatment. The survival benefit with PLEX appears more pronounced in ALF patients rather than in ACLF patients. Systematic analysis of the efficacy of PLEX to treat ALF and ACLF patients is needed. There is also a need to identify dynamic predictive scores to assess which patients with ALF or ACLF will respond to PLEX.

Von Willebrand Factor as a Biomarker for Liver Disease - An Update

The von Willebrand factor (vWF) is best known for its role in the hemostatic pathway, aiding platelet adhesion and aggregation, as well as circulating along with coagulation factor VIII, prolonging its half-life. However, vWF is more than a hemostatic protein and is a marker of endothelial dysfunction in patients with cirrhosis. The levels of vWF increase progressively as cirrhosis progresses. Despite its qualitative defects, it can support and carry out its hemostatic role and contribute to a pro-coagulant disbalance. Moreover, it has been shown to be a good noninvasive marker for predicting clinically significant portal hypertension (CSPH). The vWF has been shown to predict decompensation and mortality among cirrhosis patients independently of the stage of liver disease and severity of portal hypertension. Increased vWF levels in the setting of endothelial injury predict bacterial translocation and systemic inflammation. The vWF-to-thrombocyte ratio (VITRO) score adds to the diagnostic ability of vWF alone in detecting CSPH non-invasively. Not only have vWF levels been shown to help predict the risk of hepatocellular carcinoma (HCC) among cirrhosis patients, but they also predict the risk of complications post-resection for HCC and response to systemic therapies. vWF-induced portal microthrombi have been purported to contribute to the pathogenesis of acute liver failure progression as well as non-cirrhotic portal hypertension. The prospect of modulation of vWF levels using drugs such as non-selective beta-blockers, statins, anticoagulants, and non-absorbable antibiotics and its use as a predictive biomarker for the response to these drugs needs to be explored.

The Ratio of von Willebrand Factor Antigen to ADAMTS13 Activity: Usefulness as a Prognostic Biomarker in Acute-on-Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) has a high risk of short-term mortality. A disintegrin-like and metalloproteinase with thrombospondin type-1 motifs 13 (ADAMTS13) is a metalloproteinase that specifically cleaves multimeric von Willebrand factor (VWF). Imbalance between ADAMTS13 and VWF is associated with portal hypertension, which induces ACLF development. A previous study reported that ADAMTS13 activity (ADAMTS13:AC) and VWF antigen (VWF:Ag) are predictive biomarkers of ACLF development in patients with cirrhosis. This study investigated the changes in ADAMTS13:AC and VWF:Ag levels from before to after the development of ACLF to determine their usefulness as a prognostic biomarker in patients with ACLF. In total, 101 patients with cirrhosis were enrolled in this study. The level of ADAMTS13:AC and VWF:Ag was determined by an enzyme-linked immunosorbent assay. Cox proportional hazard regression analysis was conducted to determine independent prognostic factors for patients with liver cirrhosis in the post-ACLF group. ADAMTS13:AC levels gradually decreased in the order of non-ACLF group, pre-ACLF group, and finally post-ACLF group. VWF:Ag and the ratio of VWF:Ag to ADAMTS13:AC (VWF:Ag/ADAMTS13:AC) levels gradually increased in the order of non-ACLF group, pre-ACLF group, followed by post-ACLF group. VWF:Ag/ADAMTS13:AC and CLIF-C ACLF scores were associated with prognosis in the post-ACLF group in multivariate analysis. The cumulative survival of the post-ACLF group was significantly lower for patients with high VWF:Ag/ADAMTS13:AC (>9) compared with those with low VWF:Ag/ADAMTS13:AC (≤9) (HR: 10.72, 95% confidence interval: 1.39-82.78, p < 0.05). The VWF:Ag/ADAMTS13:AC increased according to the progression of ACLF in patients with cirrhosis and predicted prognosis in patients with cirrhosis with ACLF.

Ancient Herbal Formula Mahuang Lianqiao Chixiaodou Decoction Protects Acute and Acute-on-Chronic Liver Failure via Inhibiting von Willebrand Factor Signaling

BACKGROUND

Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) are characterized by systemic inflammation and high mortality, but there is no effective clinical treatment. As a classic traditional Chinese medicine (TCM) formula, MaHuang-LianQiao-ChiXiaoDou decoction (MHLQD) has been used clinically for centuries to treat liver diseases.

METHODS

The LPS/D-GalN-induced ALF mice model and the CCl4+LPS/D-GalN-induced ACLF mice model were used to observe the therapeutic effects of MHLQD on mice mortality, hepatocytes death, liver injury, and immune responses.

RESULTS

MHLQD treatment significantly improved mice mortality. Liver injury and systemic and hepatic immune responses were also ameliorated after MHLQD treatment. Mechanistically, proteomic changes in MHLQD-treated liver tissues were analyzed and the result showed that the thrombogenic von Willebrand factor (VWF) was significantly inhibited in MHLQD-treated ALF and ACLF models. Histological staining and western blotting confirmed that VWF/RAP1B/ITGB3 signaling was suppressed in MHLQD-treated ALF and ACLF models. Furthermore, mice treated with the VWF inhibitor ADAMTS13 showed a reduced therapeutic effect from MHLQD treatment.

CONCLUSIONS

Our study indicated that MHLQD is an effective herbal formula for the treatment of ALF and ACLF, which might be attributed to the protection of hepatocytes from death via VWF/RAP1B/ITGB3 signaling.

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.

Ratio of von Willebrand factor antigen to ADAMTS13 activity is a useful biomarker for acute-on-chronic liver failure development and prognosis in patients with liver cirrhosis

AIM

Acute-on-chronic liver failure (ACLF) is associated with a high risk of short-term mortality after progression to multiple organ failure. A disintegrin-like and metalloproteinase with thrombospondin type-1 motifs 13 (ADAMTS13) is a metalloproteinase that specifically cleaves multimeric von Willebrand factor (VWF). An imbalance between ADAMTS13 enzyme and VWF substrate is associated with liver cirrhosis progression that induces ACLF. This study examined the relationship between ADAMTS13 and VWF and ACLF development to determine whether ADAMTS13 and VWF are useful predictive biomarkers for ACLF development and prognosis of patients with liver cirrhosis.

METHODS

The study enrolled 67 patients with Child-Pugh class A and B liver cirrhosis. ADAMTS13 activity (ADAMTS13:AC) and VWF antigen (VWF:Ag) were measured using enzyme-linked immunosorbent assays. The ratio of VWF:Ag to ADAMTS13:AC (VWF:Ag/ADAMTS13:AC) was used to divide patients into two groups according to the classification and regression tree based on Gray model survival analysis.

RESULTS

Compared with patients with Child-Pugh class A liver cirrhosis, class B patients had a higher VWF:Ag/ADAMTS13:AC and a higher risk of ACLF development. Cumulative incidence of ACLF was significantly higher in patients with high (>7.9) versus low (≤7.9) VWF:Ag/ADAMTS13:AC (hazard ratio [HR], 6.50; 95% CI, 2.31-18.29; p < 0.001). Cumulative survival was significantly lower in cirrhotic patients with high versus low VWF:Ag/ADAMTS13:AC (HR 5.11; 95% CI, 1.85-14.14; p = 0.002).

CONCLUSIONS

For patients with liver cirrhosis, VWF:Ag/ADAMTS13:AC is associated with functional liver reserve and predicts the development of ACLF and the prognosis.

The Role of von Willebrand Factor Antigen in Predicting Survival of Patients with HBV-Related Cirrhosis

OBJECTIVE

The model for end-stage liver disease (MELD) scoring system cannot be used to assess the deterioration of patients with liver cirrhosis caused by infection and portal hypertension. Elevated von Willebrand factor antigen (vWF-Ag) in plasma is associated with portal pressure and complications in patients with liver cirrhosis. We aimed to evaluate whether the addition of vWF-Ag can improve the risk prediction ability of the MELD scoring system.

METHODS

A total of 228 patients with hepatitis B virus (HBV)-related liver cirrhosis were eligible for inclusion in this retrospective study. The vWF-Ag level was assessed by enzyme-linked immunosorbent assay (ELISA). The endpoint of this study was defined as the time to liver transplantation or death. Univariate and multivariate analyses were performed to assess the risk factors associated with transplant-free mortality. Receiver operating characteristic (ROC) curve analysis was used to assess potential discriminatory variables for transplant-free mortality.

RESULTS

During a median follow-up interval of 30.23 months, 124 patients (54.4%) reached the endpoint of this study. Patients who died or underwent liver transplantation had elevated levels of MELD and vWF-Ag. Moreover, vWF-Ag and MELD showed comparable predictive potential for transplant-free survival (area under the curve [AUC], vWF-Ag = 0.71; AUC, MELD = 0.73). Ultimately, vWF-Ag can significantly improve the predictive potential of MELD in determining transplant-free mortality (AUC, MELD-vWF-Ag = 0.79, P = 0.006).

CONCLUSION

An elevated vWF-Ag level was independently associated with transplant-free mortality in patients with liver cirrhosis. The inclusion of vWF-Ag in the MELD scoring system can improve mortality predictions in patients with liver cirrhosis.

Low Volume Plasma Exchange and Low Dose Steroid Improve Survival in Patients With Alcohol-Related Acute on Chronic Liver Failure and Severe Alcoholic Hepatitis - Preliminary Experience

Background

Alcohol-related acute on chronic liver failure (A-ACLF) patients have high short-term mortality and are poor candidates for steroid therapy. Plasma exchange (PLEX) improves survival in ACLF patients. We analyzed our experience with low volume PLEX (50% of plasma volume exchanged per session) and low dose steroids to treat A-ACLF patients.

Methods

We retrospectively compared the efficacy of low volume PLEX and low-dose steroids with standard medical treatment (SMT) in A-ACLF patients treated at our center between November 2017 to June 2019. The primary study outcome was one-year survival.

Results

Twenty-one A-ACLF patients in PLEX group [age 40 (29-56) years, median (range); MELD score 31 (29-46)] and 29 A-ACLF patients in SMT group [age 41.5 (28-63) years, MELD score 37 (21-48)] were studied. All 50 study patients had severe alcoholic hepatitis [mDF 84.7 (50-389)]. PLEX group patients had 3 (1-7) PLEX sessions with 1.5 (1.4-1.6) liters of plasma exchanged per session and oral Prednisolone 20 mg daily, tapered over 1 month. Kaplan Meier analysis showed better survival over 1 year in the PLEX group compared to the SMT group (P = 0.03). There was renal dysfunction in 10 patients in the PLEX group, which normalized in six patients after PLEX.

Conclusion

In this preliminary report, compared to SMT, low volume PLEX and low dose steroid improved survival over one year in A-ACLF patients with severe alcoholic hepatitis. In patients with renal dysfunction, 60% showed improvement in renal function with PLEX. Studies with a larger number of patients are needed to validate these results.

Recognizing Dysfunctional Innate and Adaptive Immune Responses Contributing to Liver Damage in Patients With Cirrhosis

The human host immune system wards off attacks by enemies such as viruses by mounting an inflammatory response which may sometimes injure self-tissues. Dysfunctional immune/inflammatory response by the host may affect the functioning of vital organs. The largest number of innate immune cells in the body resides in the liver. On encountering a new insult or injury to the liver, the innate immune system responds quickly to counter it. Acute liver insults may trigger acute liver failure or acute on chronic liver failure; these disorders are associated with a predominant innate immune response. Activation of the reticuloendothelial system (part of the innate immune response) predicts short-term and medium-term survival in patients with acute on chronic liver failure. Liver diseases associated with an aberrant adaptive immune response like autoimmune hepatitis respond well to treatment with steroids and other immunosuppressants, while those associated with innate immune dysfunction like acute on chronic liver failure do not respond well to steroids; recent reports suggest that the latter disorders may respond to therapeutic plasma exchange. How does the immune system in a patient with liver disease respond to SARS CoV2 infection? While commonly used tests in routine clinical practice provide clues to activation of different arms of immune response in patients with cirrhosis, specialized tests may help characterize this further. This review discusses the tests which reflect aberrant immune responses and treatment of patients with cirrhosis.

Reticuloendothelial activation correlates with disease severity and predicts mortality in severe alcoholic hepatitis

BACKGROUND

Overactivation of reticuloendothelial cells lining liver sinusoids - Kupffer cells (macrophages) and sinusoidal endothelial cells - may narrow the sinusoidal lumen, impair perfusion in liver microcirculation and contribute to disease severity in alcoholic hepatitis.

AIM

The aim of the article was to assess reticuloendothelial activation in patients with severe alcoholic hepatitis (SAH).

METHODS

In SAH patients, we prospectively studied baseline reticuloendothelial activation markers [serum ferritin, sCD163 and plasma von Willebrand factor (VWF) antigen] and Macrophage Activation Syndrome (MAS) criteria, correlated them with disease severity scores [model for end-stage liver disease (MELD) and Sequential Organ Failure Assessment (SOFA) scores] and analyzed their ability to predict survival over a 90-day follow-up period.

RESULTS

A total of 50 SAH patients [45 (37-49) years, median (interquartile range), 49 males, discriminant function, 76.2 (54.5-106.6); MELD score, 30 (26.2-36)] were studied. 41 SAH patients (82%) had ferritin >500 ng/mL, and all (100%) had markedly raised sCD163 and VWF levels. The median sCD163 level was 10-fold higher than healthy controls and the median VWF level was 5-fold above the upper limit of normal. In total, 37 SAH patients (74%) met MAS criteria. Reticuloendothelial activation markers correlated with MELD and SOFA scores (P < 0.05). VWF was an independent marker to predict mortality in SAH [adjusted hazard ratio, 1.002 (1.000-1.004)].

CONCLUSIONS

The reticuloendothelial system was markedly activated and correlated with disease severity scores in SAH patients.VWF predicted short-term mortality independent of MELD and sCD163. Further larger multicentric studies are needed to validate these findings.

Targeting von Willebrand factor in liver diseases: A novel therapeutic strategy?

Acute and chronic liver disease are associated with substantial alterations in the hemostatic system. Evidence from both experimental and clinical studies suggests that anticoagulants slow the progression of liver disease. Efficacy of those anticoagulant drugs is, in part, attributed to a reduction of microthrombi formation within the liver. Although anticoagulant drugs show promising results, bleeding risk associated with these drugs is an obvious drawback, particularly in patients with a complex coagulopathy driven by decreased liver function. Identifying therapies that reduce intrahepatic thrombosis with minimal bleeding risk would significantly advance the field. Among the hemostatic alterations observed in patients are substantially increased levels of the platelet-adhesive protein von Willebrand factor (VWF). In contrast, levels of A Disintegrin and Metalloproteinase with Thrombospondin motifs, the enzyme that regulates VWF activity, are significantly reduced in patients with liver disease. Highly elevated VWF levels are proposed to accelerate intrahepatic thrombus formation and thus be a driver of disease progression. Strong clinical evidence suggesting a link between liver disease and changes in VWF is now being matched by emerging mechanistic data showing a detrimental role for VWF in the progression of liver disease. This review focuses on clinical and experimental evidence supporting a connection between VWF function and the progression of acute and chronic liver diseases. Furthermore, with the recent anticipated approval of several novel therapies targeting VWF, we discuss potential strategies and benefits of targeting VWF as an innovative therapy for patients with liver disease.

Von Willebrand Factor, Factor VIII, and Other Acute Phase Reactants as Biomarkers of Inflammation and Endothelial Dysfunction in Chronic Graft-Versus-Host Disease

Chronic graft-versus-host disease (cGvHD) is an immune mediated late complication of allogeneic hematopoietic stem cell transplantation (alloHSCT). Discovery of adequate biomarkers could identify high-risk patients and provide an effective pre-emptive intervention or early modification of therapeutic strategy, thus reducing prevalence and severity of the disease among long-term survivors of alloHSCT. Inflammation, endothelial injury, and endothelial dysfunction are involved in cGvHD development. Altered levels of acute phase reactants have shown a strong correlation with the activity of several immune mediated disorders and are routinely used in clinical practice. Since elevated von Willebrand factor (VWF) and factor VIII (FVIII) levels have been described as acute phase reactants that may indicate endothelial dysfunction and inflammation in different settings, including chronic autoimmune diseases, they could serve as potential candidate biomarkers of cGvHD. In this review we focused on reported data regarding VWF and FVIII as well as other markers of inflammation and endothelial dysfunction, evaluating their potential role in cGvHD.

Rodenticidal hepatotoxicity: Raised plasma Von Willebrand factor levels predict in-hospital survival and preliminary report of the outcome of Von Willebrand factor reducing management protocol

BACKGROUND

High Von Willebrand factor (VWF) levels may predispose to multi-organ failure in acute liver failure (ALF). In rodenticide-induced hepatotoxicity patients, we analyzed if plasma VWF levels predicted survival and also the outcome of VWF lowering by N-acetyl cysteine (NAC), fresh frozen plasma (FFP) infusions, and plasma exchange (PLEX).

METHODS

We retrospectively analyzed prospectively collected data. Hepatotoxicity was classified as uncomplicated acute hepatitis (UAH), acute liver injury (ALI), and ALF. ALF patients, if not opting for liver transplantation, had PLEX and NAC; ALI patients received NAC ± FFP (PLEX, if worsening); UAH patients had NAC. Plasma VWF antigen was measured (normal, 50% to 150%). In-hospital survival was analyzed as discharged alive or died/discharged in a terminal condition (poor outcome).

RESULTS

Twenty-four consecutive rodenticide-induced hepatotoxicity patients (UAH in 1, ALI in 20, ALF in 3) from December 2017 to January 2019 were studied. Baseline VWF levels were 153%, 423 (146-890)% median (range), and 448 (414-555)% in UAH, ALI, ALF patients; model for end-stage liver disease (MELD) scores were 11, 24 (12-38), 36 (32-37) and in-hospital survival rates were 100%, 85%, 67%, respectively. VWF levels were higher in patients with poor outcome (555 [512-890]%) than in those discharged alive (414 [146-617]%) (p-value = 0.04). The area under the receiver operating curve of the VWF level, MELD score, and sequential organ failure assessment score to predict survival was 0.92, 0.84, and 0.66, respectively. Of 4 patients meeting criteria for liver transplantation (none had transplantation), 3 (75%) survived.

CONCLUSIONS

High VWF levels predict poor outcome in rodenticide-induced hepatotoxicity. VWF reduction may be useful in such patients.

Systematic review: role of elevated plasma von-Willebrand factor as predictor of mortality in patients with chronic liver disease

In this systematic review, we aimed to assess role of plasma von-Willebrand factor (vWF), an endothelial activation marker, as prognostic marker in patients with chronc liver disease [cirrhosis and acute-on-chronic liver failure (ACLF)]. We searched published databases using predefined keywords to identify all studies up to June 2018, in which plasma vWF (antigen or activity assay) was used as prognostic marker predicting mortality in patients with chronic liver disease. Relevant extracted data from selected studies were narratively summarized. The individual study's area under ROC curve for plasma vWF as a predictor of mortality was pooled and meta-analyzed. Six studies (cirrhosis: 5; ACLF: 1) with an aggregate data of 765 patients (cirrhosis: 715 patients; ACLF: 50 patients) were included. Baseline plasma vWF-antigen was an independent predictor of medium-term mortality in patients with cirrhosis (summary area under the curve: 0.74; 95% confidence interval: 0.70-0.79) with an optimal cutoff of 318% (216-390%; median, range) over a period of 25.6 months (23.6-33 months). Plasma vWF also predicted short-term (over 7 days) mortality in patients with ACLF. Plasma vWF levels correlated with Child's score, model for end-stage liver disease (MELD) score and hepatic venous pressure gradient and performed as well as MELD score in predicting mortality in patients with cirrhosis and ACLF. Baseline plasma vWF level predicts mortality over a medium term (1-3 years) in cirrhosis and over a short term (1 week) in ACLF patients. The marked elevation of baseline plasma vWF levels in ACLF patients was associated with drastic truncation of survival when compared with cirrhosis patients.

Perioperative von Willebrand factor dynamics are associated with liver regeneration and predict outcome after liver resection

von Willebrand Factor (vWF) was found to mediate platelet influx during the early phase of liver regeneration in mice. Furthermore, increased vWF-antigen (vWF-Ag) levels were shown to be predictive for outcome of patients with chronic liver disease. Accordingly, we aimed to assess the relevance of perioperative vWF-Ag dynamics in terms of liver regeneration and clinical outcome in patients undergoing liver resection (LR). Accordingly, we observed that vWF-Ag and its activity-estimated by ristocetin cofactor measurement-increased immediately after induction of liver regeneration and was associated with platelet accumulation within the liver. However, a significant vWF-Ag burst was only observed in patients with unaffected postoperative liver regeneration. E-selectin, as an established marker for endothelial cell activation, was found to correlate with vWF-Ag in the liver vein after induction of liver regeneration (R = 0.535, P = 0.022). Preoperative vWF-Ag levels significantly predicted postoperative liver dysfunction (LD; N = 95; area under the curve, 0.725; P = 0.009). Furthermore, a cutoff of vWF-Ag ≥182% was defined to identify patients with a higher risk for postoperative LD or morbidity. This was confirmed within an independent mulitcenter validation cohort (N = 133). Ultimately, multivariable analysis revealed that vWF-Ag was an independent predictor of postoperative LD and morbidity.

CONCLUSION

Within this study, we were able to provide evidence that an initial vWF burst is required to allow for adequate platelet accumulation and concomitant liver regeneration post-LR and might be abolished as a consequence of intrahepatic endothelial cell dysfunction. We were further able to reveal and validate the potential of preoperative vWF-antigen levels to predict poor postoperative outcome in patients undergoing LR. Despite the pathophysiological relevance of our findings, vWF-Ag seems to be a valuable tool for preoperative risk assessment in patients undergoing LR. (Hepatology 2018;67:1516-1530).