Significant Association between Serum Levels of Von Willebrand Factor (vWF) Antigen with Stages of Cirrhosis

The Addition of C-Reactive Protein and von Willebrand Factor to Model for End-Stage Liver Disease-Sodium Improves Prediction of Waitlist Mortality

BACKGROUND AND AIMS

Patients with cirrhosis on the liver transplant (LT) waiting list may die or be removed because of complications of portal hypertension (PH) or infections. von Willebrand factor antigen (vWF-Ag) and C-reactive protein (CRP) are simple, broadly available markers of these processes.

APPROACH AND RESULTS

We determined whether addition of vWF-Ag and CRP to the Model for End-Stage Liver Disease-Sodium (MELD-Na) score improves risk stratification of patients awaiting LT. CRP and vWF-Ag at LT listing were assessed in two independent cohorts (Medical University of Vienna [exploration cohort] and Mayo Clinic Rochester [validation cohort]). Clinical characteristics, MELD-Na, and mortality on the waiting list were recorded. Prediction of 3-month waiting list mortality was assessed by receiver operating characteristics curve (ROC-AUC). In order to explore potential mechanisms underlying the prognostic utility of vWF-Ag and CRP in this setting, we evaluated their association with PH, bacterial translocation, systemic inflammation, and circulatory dysfunction. In the exploration cohort (n = 269) vWF-Ag and CRP both improved the predictive value of MELD-Na for 3-month waitlist mortality and showed the highest predictive value when combined (AUC: MELD-Na, 0.764; MELD-Na + CRP, 0.790; MELD-Na + vWF, 0.803; MELD-Na + CRP + vWF-Ag, 0.824). Results were confirmed in an independent validation cohort (n = 129; AUC: MELD-Na, 0.677; MELD-Na + CRP + vWF-Ag, 0.882). vWF-Ag was independently associated with PH and inflammatory biomarkers, whereas CRP closely, and MELD independently, correlated with biomarkers of bacterial translocation/inflammation.

CONCLUSIONS

The addition of vWF-Ag and CRP-reflecting central pathophysiological mechanisms of PH, bacterial translocation, and inflammation, that are all drivers of mortality on the waiting list for LT-to the MELD-Na score improves prediction of waitlist mortality. Using the vWFAg-CRP-MELD-Na model for prioritizing organ allocation may improve prediction of waitlist mortality and decrease waitlist mortality.

Platelet function in dogs with chronic liver disease

OBJECTIVES

To assess platelet function, buccal mucosal bleeding time and plasma von Willebrand factor concentration in dogs with chronic inflammatory and/or fibrotic liver disease and to compare results with those obtained in healthy dogs.

MATERIALS AND METHODS

Preliminary study including 18 dogs with chronic inflammatory and/or fibrotic liver disease undergoing liver biopsy and 18 healthy age-matched control dogs. Platelet function was assessed by measuring closure time with the PFA-100® analyser using adenosine diphosphate (ADP) as an agonist. Buccal mucosal bleeding time, closure time and plasma von Willebrand factor antigen were measured in dogs in both groups. After undergoing ultrasound-guided needle biopsy, dogs were monitored for haemorrhage to determine if there was an association of any measurement with post-biopsy bleeding.

RESULTS

The closure time was not different between the liver disease group (median 76.3; range 53 to 118.5 seconds) and control group (72.8; 57 to 89.5 seconds). The buccal mucosal bleeding time was longer in the liver disease group (median 138; range 95 to 229 seconds) than the control group (103; 63 to 200 seconds). The plasma von Willebrand factor antigen concentration was not different between the liver disease group (median 203; range 109 to 351%) and control group (165.5; 63 to 246%).

CLINICAL SIGNIFICANCE

In this study, dogs with chronic necroinflammatory and/or fibrotic liver disease did not have overt, clinically relevant derangements in platelet function as assessed by buccal mucosal bleeding time, closure time and von Willebrand factor analysis. In addition, none of the dogs undergoing percutaneous ultrasound-guided biopsy in the study exhibited bleeding complications post-biopsy procedure.

Role of the von Willebrand factor and the VITRO score as predictors for variceal bleeding in patients with hepatitis C-related cirrhosis

BACKGROUND

Noninvasive methods have been established to detect clinically significant portal hypertension in liver cirrhosis with variable limitations. The von Willebrand factor (vEF) has been found to increase in liver cirrhosis.

AIM

The aim of this study was to explore the vEF and VITRO (von Willebrand factor antigen/platelet ratio) score in the prediction of variceal bleeding in patients with portal hypertension.

MATERIALS AND METHODS

Fifty patients with hepatitis C-related liver cirrhosis (25 patients with variceal bleeding and 25 without variceal bleeding) as well as 80 healthy controls were included. Laboratory investigations and upper gastrointestinal endoscopy were performed in all patients. Serum vEF was measured in the patient and the control group. The VITRO score was calculated.

RESULTS

The mean levels of the vEF antigen and the VITRO score were higher in patients with variceal bleeding compared with patients without variceal bleeding and controls (P<0.001). At levels of at least 100.1 ng/ml and at least 0.732, the vEF and the VITRO score could predict variceal bleeding with a sensitivity and a specificity of 92 and 99.9% for the vEF and 80 and 68% for the VITRO score (area under the curve=0.982 and 0.843), respectively. Levels of vEF were correlated positively with esophageal varices grade.

CONCLUSION

Serum vEF level and the VITRO score are potential noninvasive biomarkers for the prediction and risk stratification of variceal bleeding in hepatitis C-related liver cirrhosis.