Von Willebrand Factor Values Research Articles

Evaluation of Von Willebrand Factor in Dogs with Parvoviral Enteritis

Canine parvoviral enteritis may lead to coagulopathy in various ways. In recent years, the importance of von Willebrand factor has become the focus of more attention in infectious diseases. The aim of this study was to determine the importance of von Willebrand factor level and coagulation parameters in dogs with parvoviral enteritis. The experimental group of this study consisted of 20 dogs with parvoviral enteritis of different breeds aged 2-6 months, and the control group consisted of 10 healthy dogs aged 2-6 months. Blood samples were taken from the dogs included in the experimental group at the 0th hour, 24th hour and before discharge, and only at the 0th hour from the healthy puppies in the control group The 0th and 24th hour von Willebrand factor values of the trial were significantly higher than the control group. The 0th hour Prothrombin Time of the trial was significantly prolonged compared to the control group. The 0th hour Activated Partial Thromboplastin Time value of the trial was significantly prolonged compared to the before-discharge and control group. The before-discharge fibrinogen level was determined to be significantly lower than at 0th and 24th hours of the trial. In conclusion, von Willebrand factor concentrations, which increase significantly in dogs with parvoviral enteritis compared to healty animals, can be evaluated as an acute phase protein. Prolongation of Prothrombin Time and Activated Partial Thromboplastin Time and no significant change in fibrinogen and D-dimer values demonstrated that dogs with parvoviral enteritis were in hypercoagulation state without dissemine intravascular coagulation.

Value of Von Willebrand Factor and Soluble Intercellular Adhesion Molecule-1 in the Evaluation of Primary Aldosteronism as well as Nutritional Status in Hypertensive Patients

Primary aldosteronism is a common clinical syndrome in hypertensive patients. Early identification and timely treatment of primary aldosteronism are of great significance to improve the prognosis of patients. Endothelial dysfunction is currently considered an important potential pathological change in primary aldosteronism. In this study, we observed that the levels of von Willebrand factor and soluble intercellular adhesion molecule-1 were significantly elevated in primary aldosteronism and were closely associated with pathological progression. Von Willebrand factor and soluble intercellular adhesion molecule-1 are important adhesion factors in blood, and their levels are directly related to blood viscosity. Meanwhile, both markers showed excellent efficacy in diagnosing primary aldosteronism in hypertensive patients. Additionally, an inverse correlation of soluble intercellular adhesion molecule-1 and primary aldosteronism with the nutritional protein levels of primary aldosteronism patients was identified, which also confirms the promising potential of von Willebrand factor and soluble intercellular adhesion molecule-1 for dynamic nutritional status assessment in primary aldosteronism. These findings are of great significance for the future clinical diagnosis and treatment of primary aldosteronism.

Haemostaseological Changes of VWF and FVIII during Pregnancy and the Oestrus Cycle in a Porcine Model of Von Willebrand Disease

Pregnancy and the oestrus cycle are challenging for female patients suffering from von Willebrand disease (VWD). Therefore, our study aimed to investigate the changes in von Willebrand factor (VWF) and factor VIII (FVIII) during pregnancy and the oestrus cycle in our porcine model of von Willebrand disease compared with the wild-type. Plasma analyses regarding primary hemostasis, secondary hemostasis, and VWF multimers, as well as immunohistochemistry analyses of VWF in the uterus and ovary, were performed. For levels of VWF and FVIII activities, significant elevations were seen in the last trimester. Primary hemostasis improved towards the end of pregnancy. In the oestrus cycle, significantly lower VWF values can be seen in the immunohistochemistry of the ovaries during the oestrus, while values were highest in the metoestrus. VWF multimer patterns in pigs were similar to the ones in human VWD patients. In summary, the course of VWF and FVIII during pregnancy and the oestrus cycle in porcine VWD were investigated for the first time. The porcine model seems to be suitable for haemostaseological studies on VWD. This provides an advantage for investigating reproduction-related bleeding and understanding the underlying mechanisms of post-partum hemorrhage or miscarriage in women with VWD.

Predictive value of von Willebrand factor for venous thromboembolism in critically ill patients based on propensity score matching

To analyze the predictive value of von Willebrand factor (vWF) for venous thromboembolism (VTE) of patients in intensive care unit (ICU) by using propensity score matching (PSM). Patients admitted to ICU of the Second Affiliated Hospital of Kunming Medical University from December 2020 to June 2022 who stayed in ICU for ≥72 hours and underwent daily bedside vascular ultrasound screening were included. Baseline data such as age, gender, primary disease, and chronic comorbidities were collected. Coagulation indexes before admission to ICU and 24 hours and 48 hours after ICU admission were collected, including prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), international normalized ratio (INR), fibrinogen (Fib), fibrin monomer (FM), vWF, D-dimer, antithrombin III (ATIII), etc. Patients were divided into VTE group and non-VTE group according to whether they had VTE or not [diagnosis of VTE: patients underwent daily ultrasound screening of bedside blood vessels (both upper and lower limbs, visceral veins), and those suspected of having thrombosis were confirmed by ultrasonographer or pulmonary angiography]. Using PSM analysis method, the VTE group was used as the benchmark to conduct 1 : 1 matching of age, whether there was malignant tumor, whether there was infection, whether there was diabetes, and coagulation indicators before admission to ICU. Finally, the cases with balanced covariates between the two groups were obtained. The risk factors of VTE were analyzed by multivariate Logistic regression analysis. Receiver operator characteristic curve (ROC curve) was drawn to evaluate the predictive value of vWF in the occurrence of VTE in critically ill patients. A total of 120 patients were enrolled, of which 18 (15.0%) were diagnosed with VTE within 72 hours after admission to ICU, and 102 (85.0%) were not found to have thrombus in ICU. Before PSM, there were significant differences in age, gender, proportion of malignant tumor and infection, and coagulation indexes between VTE group and non-VTE group. After PSM, 14 pairs were successfully matched, and the unbalanced covariables between the two groups reached equilibrium. Multivariate Logistic regression analysis showed that vWF was an independent risk factor for VTE at 48 hours after ICU admission in critically ill patients [odds ratio (OR) = 1.165, 95% confidence interval (95%CI) was 1.000-1.025, P = 0.004]. ROC curve analysis showed that the area under the ROC curve (AUC) of vWF at 48 hours after ICU admission for predicting VTE was 0.782, 95%CI was 0.618-0.945, P = 0.007. When the optimal cut-off value was 312.12%, the sensitivity was 67.7% and the specificity was 93.0. Dynamic monitoring of vWF is helpful to predict the occurrence of VTE in ICU patients, and vWF at 48 hours after ICU admission has certain value in predicting the occurrence of VTE.

The Impacts of Genetic Polymorphisms on the Von Willebrand Factor Level in Type 1 Von Willebrand Disease

Background: von Willebrand disease (VWD) is the most common inherited bleeding disease, which results from deficiency or defect of von Willebrand factor (VWF). In type 1 VWD, there are only 53-81% patient whose mutations of VWF gene can be identified. Some studies reported that variants outside the VWF gene may also contribute to the VWF level. There are 7 genetic variants of single nucleotide polymorphism ( SNP ) reported to be associated with the variation of VWF levels, including CLEC4M, STXBP5, SCARA5, ABO, VWF, STAB2 and UFM1. The aims of this study were to explore the frequency of SNPs of the 7 genes among type 1 VWD patients and the effects of the 7 genetic variants on the VWF levels in type 1 VWD patients. Patients and methods: There were 62 patients ( the ratio of M/F: 1 ) with type 1 VWD enrolled in this study, including 35 (56.5%) patients with found mutations of VWF gene. Each patient's bleeding symptoms were assessed by the MCMDM-1 VWD bleeding score. The results of VWF levels: VWF:Ag and VWF activity ( VWF:ACL or VWF:RCo ) and FVIII: C at the VWD diagnosis were retrospectively collected, as shown in Table 1. Each enrolled patient's genomic DNA was extracted and the SNPs of the 7 gene were targeted by PCR amplification followed by direct sequencing. Results: There was high correlations between VWF:Ag and VWF activity ( r = 0.73, p < 0.0001 ) and between VWF:Ag and FVIII:C ( r = 0.60, p < 0.0001 ), respectively. The patients without variant ( A/A) of UFM1 has significantly lower median VWF:Ag of 33% than 44.7% of patients with heterozygous variant ( A/C ) type ( p = 0.033 ). Patients without variant (A/A ) of STXBP gene had both significantly lower median value of VWF:Ag ( 31.9% vs 46.1%, p = 0.017 ) and VWF activity (26.55% vs 30.4%, p = 0.0467 ) than those patients with heterozygous variant ( A/G ). Four alleles substitution of SNP of UFM1( C>A ) and STXBP genes ( G>A ) variant has remarkably lowest median VWF antigen level of 27.4%, which was significantly lower than 43.05% of the three alleles substitution ( p = 0.0014 ) and the 48.6% of the two alleles substitution ( p = 0.0279 ), as shown in Figure 1. Conclusions: Our study demonstrates that both C to A variant of UFM1 gene and G to A variant of STXBP5 gene were associated with lower VWF: Ag level than those without variant, respectively. The combination of four allelic variant of UFM1 and STXBP5 genes had the most reducing effect on VWF: Ag level.

Utility of Assessing Primary Hemostasis By Determining Platelet Function and Von Willebrand Factor in Patients with Myeloproliferative Neoplasms

VWF Changes in primary hemostasis have been implicated in thrombotic and bleeding complications in myeloproliferative neoplasms (MPN), so their evaluation could be useful in the management of these patients. We studied primary hemostasis in 248 patients with essential thrombocythemia-type MPN (TE n=129), polycythemia vera (PV n=71) and myelofibrosis (MF n=48). Von Willebrand antigen (VWF:Ag) (normal: 60-160 U/dL), von Willebrand factor (VWF) activity (VWF:GPIbM) (normal: 60-160 U/dL) and closure time with the platelet function analyzer (PFA-200) (pathological: collagen-Epinephrine channel > 200 seconds; collagen-ADP channel > 140 seconds) were assessed. VWF:GPIbM < 60 U/dL and a VWF:GPIbM / VWF:Ag ratio < 0.7 were considered to be suggestive of acquired von Willebrand disease (aVWD). In antiplatelet patients with acetyl salicílic acid (ASA), we defined in vitro resistance as a PFA-200 Col-Epi time < 200 seconds. The results were correlated with the diagnosis, hematological values, conventional or NGS genotype (n=176) and treatment at the time of the study. Patients with thrombocytopenia < 50x10 9/L were excluded from the PFA-200 analysis. Table 1 describes the clinical variables of the patients. GPIbM was decreased in 14 cases, increased in 85 cases, and normal in the rest. We identified a direct correlation with age (β=0.29, R2=0.08, p=0.001), and an inverse correlation with the number of platelets (β=-0.45, R2=0.20, p<0.001), independent of the genotype. . We found elongated PFA-200 in the Col-Epi and Col-ADP channels in 129 (54%) and 63 (26%) cases, respectively. In 10 (4%) patients we found parameters suggestive of avWD. All of them had thrombocytosis. Elevated platelet count (>600x109/L) was associated with VWF values suggestive of aVWD, with a sensitivity and specificity of 90% and 83%, respectively (AUC: 0.938, 95%CI: 0.896-0.980). Of the 99 patients not on antiplatelet therapy, 31 (31%) had an elongated PFA-200. Elongated PFA-200 was associated with lower Hb, higher leukocytes, higher platelets, higher JAK2 mutational load, lower VWF:GPIbM, and CALR genotype. This alteration was observed in 71% of patients with the CALR genotype. In multivariate analysis, decreased VWF:GPIbM (OR: 0.98, 95%CI: 0.97-0.99, p=0.001) and CALR mutation (OR: 0.98, 95%CI: 0.97- 0.99, p=0.001), maintained their value. Of the 130 patients receiving ASA, in vitro resistance was found in 31 cases (24%) (PV 30%, TE 25%, MF 0%). ASA resistance was associated with a higher platelet count and higher VWF:GPIbM. 50% of the patients with increased VWF:GPIbM (>160 U/dL) had resistance to ASA, showing VWF:GPIbM as an independent variable in the multivariate analysis.

Initial von Willebrand factor antigen values in adolescent females predict future values.

Diagnosing von Willebrand Disease (VWD) in adolescent females is challenging as menstruation and physiologic stress elevate von Willebrand factor (VWF) laboratory values. To develop a VWF prediction model for adolescent females based on initial VWF results. We identified female patients aged 9 to 21 years with any VWF laboratory test over a 5-year period (2017-2021) at any Texas Children's Hospital facility. Patient demographics, VWF testing, haemoglobin concentration, serum ferritin and site of clinical testing were collected (initial and subsequent laboratory evaluations). A Bayesian linear regression model was developed. Prediction intervals were analysed to identify thresholds for patients in whom repeat testing was unlikely to identify low VWF levels (<50%), consistent with VWD. A total of 6125 adolescent females underwent VWF testing; 1204 (19.7%) had repeat testing. Based on the prediction model, initial VWF antigen values of 80%, 90% and ≥100% carried a 92.6%, 96.6% and ≥98.0% probability of having repeat normal repeat VWF values, respectively.Subjects assessed in outpatient adolescent medicine or gynaecology clinics were more likely to have low VWF values compared to those assessed in the acute care setting (p<.001). Median presenting haemoglobin and serum ferritin were 12.4g/dL and 13ng/mL, respectively and were similar in those with normal versus low VWF antigen values. Repeat testing in adolescent females whose initial VWF antigen values are ≥90% is unlikely to identify additional patients with VWD. Iron deficiency screening should be performed in all adolescent females.

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

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. 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. 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. 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.

Predictive value of von Willebrand factor for venous thrombosis in patients with chronic heart failure complicated with atrial fibrillation after anticoagulant therapy

BackgroundWe investigated the value of von Willebrand factor (vWF) in predicting venous thrombosis in patients with chronic heart failure complicated with atrial fibrillation after anticoagulation therapy.MethodsTotally, 126 patients with chronic heart failure complicated with atrial fibrillation who were treated with anticoagulant therapy and 60 healthy individuals were enrolled. One year after anticoagulant therapy, venous thrombosis occurred in 19 patients. Clinical data of patients were collected. The plasma vWF activity was detected and compared. The logistic regression analysis was used to analyze the influencing factors of vWF. ROC curve was used to evaluate the predictive value of plasma vWF.ResultsPlasma vWF activity was significantly higher in patients with heart failure and atrial fibrillation than control subjects (P < 0.01). The vWF activity in patients with venous thrombosis was significantly higher than that in patients without venous thrombosis (P < 0.01). ROC curve analysis showed that the cut-off value of vWF activity for venous thrombosis within one year after anticoagulant therapy was 267.5%, and the AUC was 0.742 (95% CI: 0.764–0.921, P < 0.05). The sensitivity was 80.0%, and the specificity was 63.6%. Factors of diabetes, myocardial ischemia, old myocardial infarction, and lower extremity atherosclerosis, but not sex, age, coronary heart disease, hypertension, and cardiac function, had significant effect on vWF activity (P < 0.05). Logistic regression analysis showed that vWF activity was significantly related with atherosclerosis of lower limbs and old myocardial infarction, but not significantly related with diabetes and myocardial ischemia. The risk of venous thrombosis in patients with vWF activity greater than 267.5% was 10.667 times higher than that in patients with vWF activity less than 267.5% (P < 0.05).ConclusionThe vWF activity greater than 267.5% has clinical predictive value for the risk of lower extremity venous thrombosis in patients with chronic heart failure complicated with atrial fibrillation within 1 year of anticoagulant therapy.

Features of the endothelial status in patients with gastric cancer and its impact on surgical treatment outcomes

BACKGROUND: The incidence of gastric cancer is still high and holds the leading place in the structure of oncological pathology in the world. Prognostic aspects in the treatment of generalized forms of gastric cancer are currently under revision.&#x0D; AIM: To study functional status of vascular endothelium in patients with gastric cancer in perioperative period and evaluate its influence on the outcomes of surgical treatment.&#x0D; MATERIALS AND METHODS: A prospective, randomized study was conducted from 2009 to 2019. Two populations were studied: healthy individuals (control group, n=40); patients diagnosed with gastric cancer (general group, n=122). Patients with gastric cancer underwent gastrectomy with lymphodissection.&#x0D; The functional state of the vascular endothelium was studied: the volume of circulating endotheliocytes (CCE); the level of von Willebrand factor (VF) and the degree of endothelium-dependent vasodilation (EDV). To study their prognostic significance we calculated a conventional cut-off point.&#x0D; RESULTS: The general group patients were divided into 2 subgroups: the main group the laparoscopic access (n=54) and the comparison group the laparotomy access (n=68).&#x0D; Endothelial dysfunction (EDF) correction with Glutargin 1.0 g per day in combination with Enalapril 2.5 mg per day was additionally used in the main subgroup.&#x0D; In the main group, the values of CCE and VF were lower (8.33.0 and 84.621.3, respectively) and the values of EDV were higher (13.73.9) in contrast to the comparison group (p 0.0001).&#x0D; Use of the EDF correction method in the main group resulted in a 4.4-fold and 5.1-fold decrease in CCE and VF concentrations, respectively, and a 4.3-fold normalization of EDV (p 0.0001). Increase of CCE concentration more than 7.0 per 103 platelets; PV more than 120 g/ml, as well as decrease of EDV below 14% in the study stages increased the risk of postoperative complications by 2.9; 1.7 and 1.8 times, respectively (p 0.0001).&#x0D; The incidence of surgical complications was 19.7% and non-surgical complications 31.1%. Hospital mortality was 3.3% and out-of-hospital mortality with up to three years follow-up was 13.1%.&#x0D; The number of purulent-septic complications in the main group was 2.9 times lower, and the rate of thrombotic complications was 4 times lower than in the comparison group (p 0.05).&#x0D; CONCLUSION: Combined use of laparoscopic technique by EDF medication correction reduces manifestations of stress reaction and decreases the potential risk of complications development in the postoperative period. Elevation of CCE, as well as EDV decrease beyond the relevant excision points in patients with gastric cancer in the perioperative period are prognostic predictors of the risk of purulent-septic and thrombotic complications development.

Prognostic value of von Willebrand factor levels in patients with metastatic melanoma treated by immune checkpoint inhibitors

BackgroundAn increased incidence of thrombotic complications associated with an increased mortality rate has been observed under immune checkpoint inhibition (ICI). Recent investigations on the coagulation pathways have highlighted the direct...

Plasma VWF: Ag levels predict long-term clinical outcomes in patients with acute myocardial infarction.

A vital role in coronary artery disease is played by Von Willebrand factor (VWF), which serves as a bridge between platelets and the subendothelial matrix after vessel damage. The purpose of the study was to assess the validity of plasma VWF antigen (VWF: Ag) levels as a predictor of clinical outcomes after acute myocardial infarction (AMI). Three hundred and seventy-four patients were studied following coronary angiography, including 209 patients suffering from acute myocardial infarction and 165 healthy participants. Coronary angiography was followed by measurement of plasma VWF: Ag levels. Over a 2-year follow-up period, major adverse cardiopulmonary and cerebrovascular events (MACEs) were the primary endpoint. All-cause mortality was investigated as a secondary endpoint. When compared to controls, patients with AMI had mean plasma VWF: Ag levels that were ~1.63 times higher (0.860 ± 0.309 vs. 0.529 ± 0.258 IU/ml; P < 0.001). The plasma VWF: Ag levels were substantially higher in patients who experienced MACEs after myocardial infarction vs. those without MACEs (1.088 ± 0.253 vs. 0.731 ± 0.252 IU/ml; P < 0.001). For predicting long-term MACEs using the optimal cut-off value (0.7884 IU/ml) of VWF: Ag, ROC curve area for VWF: Ag was 0.847, with a sensitivity of 87.2% and a specificity of 66.3% (95%CI: 0.792-0.902; P = 0.001). Two-year follow-up revealed a strong link between higher plasma VWF: Ag levels and long-term MACEs. At the 2-year follow-up, multivariate regression analysis revealed an independent relationship between plasma VWF: Ag levels and MACEs (HR = 6.004, 95%CI: 2.987-12.070). We found evidence that plasma VWF: Ag levels were independent risk factors for AMI. Meanwhile, higher plasma VWF: Ag levels are associated with long-term MACEs in people with AMI.

To Repeat or Not Repeat, That Is the Question: Von Willebrand Testing in Adolescent Girls with Heavy Menstrual Bleeding

Heavy menstrual bleeding (HMB) is often the initial manifestation of a bleeding disorder in adolescent females. Von Willebrand disease (VWD) is the most common bleeding disorder, yet diagnosing VWD in HMB is challenging given that menstruation, acute illness, and physiologic stress all elevate von Willebrand factor (VWF) laboratory values. Thus, the interpretation of initial VWF results may be challenging, and the need for repeat VWF testing in this population may be unclear. The aims of this study were to understand VWD diagnostic testing patterns in adolescent females evaluated within the Texas Children's Hospital (TCH) network and to develop a prediction model to determine whether repeat testing was indicated based on initial VWF testing results. Female patients aged 9 to 21 years who had any VWF laboratory test over a 5-year period (January 1, 2017 through December 31, 2021) at a TCH facility (greater Houston metroplex) were identified. Data collection included patient demographics, VWF-related testing (antigen and activity [ristocetin cofactor or glycoprotein Ib]), factor VIII activity, hemoglobin concentration and serum ferritin. Both initial and subsequent laboratory evaluations were collected. The site of clinical testing was also identified, including both acute care settings (emergency department, inpatient, and critical care), and outpatient settings (adolescent medicine, gynecology, hematology, otolaryngology, other outpatient TCH primary care clinics). To ensure that subsequent laboratory testing was not mistaken as the initial testing within the cohort, patients who underwent VWF laboratory testing from 2010 to 2016 were excluded. VWF levels obtained after the administration of VWF replacement products were also removed from the data set. Based on the ASH ISTH NHF WFH 2021 guidelines on the diagnosis of VWD, and with the presumption that adolescents with HMB met the criteria for abnormal bleeding, we analyzed the need to repeat VWF testing to identify any patient with a low VWF antigen level consistent with Type 1 VWD, defined as <50%. A Bayesian linear regression model was developed to predict follow-up VWF antigen levels using the initial levels. Prediction intervals were analyzed to identify thresholds for patients who may not require retesting. This study was approved by the Baylor College of Medicine Institutional Review Board. A total of 6,125 adolescent females underwent VWD testing at a TCH facility during the study period; 1,204 (19.7%) had repeat VWF antigen values performed and were included in the analysis (TABLE). Of those, 1,037 subjects (86.1%) had normal VWF values (≥50%) on both initial and repeat testing. Seventy-five subjects (6.2%) had low VWF antigen values on both initial and repeat testing. Ninety-two subjects had discrepant initial and repeat testing. Forty-seven (3.9%) had low initial VWF antigen values that normalized on subsequent testing. Forty-five (3.7%) had normal initial VWF values that subsequently fell below 50%. Based on our prediction model, in subjects with initial VWF antigen values of ≥80% there was ≥97% probability of having normal repeat VWF values. Values of ≥100% carry a 99.4% probability of having normal repeat VWF testing (FIGURE). No association was identified between age and VWF antigen level. Subjects assessed in outpatient adolescent medicine or gynecology clinics were more likely to have low VWF values (on any testing) whereas subjects with normal values were more frequently assessed in the acute care settings (P<0.001). The median serum ferritin and hemoglobin values in the cohort were 13 ng/ml and 12.8 g/dl, respectively, without a significant difference between those with normal versus low VWF antigen values. Repeat testing in adolescent females whose initial VWF antigen testing values are 80% and higher is unlikely to identify more patients with VWF values below 50%. In this cohort, subjects undergoing hemostatic evaluation, presumably for HMB, by adolescent medicine or gynecology providers were more likely to identify abnormal VWD testing compared to the acute care setting. Iron deficiency screening should be considered for all adolescent females with HMB and not just those girls with a confirmed bleeding disorder. Additional studies are needed to determine the effects of iron deficiency and anemia on VWD laboratory testing in adolescent females with HMB and to validate the accuracy of the prediction model. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Prognostic value of von-Willebrand factor in patients with liver cirrhosis and its relation to other prognostic indicators.

BACKGROUNDVon-Willebrand factor (vWF) disposes certain prognostic value in patients with liver cirrhosis, but its relation to other prognostic indicators has not been fully investigated. AIMTo analyze the relation between vWF and other prognostic indicators in cirrhotic patients and to evaluate its prognostic value for mortality. METHODSThis analytic prospective study was carried out in a tertiary center and initially enrolled 71 patients with liver cirrhosis and portal hypertension. It analyzed the relation between vWF and the stage of the disease and several inflammatory and prognostic indicators. The prospective analysis, performed on a sample of 63 patients, evaluated the association between the selected variables [vWF, Model for End-stage Liver Disease (MELD) score, C-reactive protein (CRP), ferritin, vitamin D, activated partial thromboplastin time, thrombin time, D-dimer concentration] and the survival time as well as their predictive value in terms of 3-mo, 6-mo and 1-year mortality.RESULTSvWF was significantly higher in patients with higher Child-Turcotte-Pugh class (P = 0.0045), MELD group (P = 0.0057), ferritin group (P = 0.0278), and D-dimer concentration (P = 0.0232). vWF significantly correlated with D-dimer concentration, ferritin, CRP, International Normalized Ratio, and MELD, Child-Turcotte-Pugh, Sequential Organ Failure Assessment, and CLIF-consortium organ failure (CLIF-C OF) scores. vWF, MELD score, and CRP were significantly associated with death and were significant predictors of 3-mo, 6-mo, and 1-year mortality. Each vWF unit significantly increased the probability for 3-mo mortality by 1.005 times (P = 0.008), for 6-mo mortality by 1.006 times (P = 0.005), and for 1-year mortality by 1.007 times (P = 0.002). There was no significant difference between the diagnostic performance of vWF and MELD score and also between vWF and CRP regarding the 3-mo, 6-mo, and 1-year mortality.CONCLUSIONIn patients with liver cirrhosis, vWF is significantly related to other prognostic indicators and is a significant predictor of 3-mo, 6-mo, and 1-year mortality similar to MELD score and CRP.

The clinical value of von Willebrand factor and VITRO score in evaluating disease progression in patients with HBV infection

Objective: To explore the clinical value of von Willebrand Factor (vWF) and VITRO score (vWF:Ag/platelet count) in assessing disease progression in patients with HBV infection. Methods: Randomly collect relevant clinical data of 308 patients with HBV infection (including 154 cases of chronic hepatitis B, 66 cases of hepatitis B cirrhosis in compensatory period, 88 cases of hepatitis B cirrhosis in decompensated period) from December 1, 2018 to January 5, 2021 in the Second Affiliated Hospital of Chongqing Medical University. The vWF values are measured by a uniform optical method, and all data are included using a uniform standard. Analyze the difference and significance of plasma vWF level and VITRO score in chronic hepatitis B, hepatitis B cirrhosis in the compensatory phase and decompensated phase. Results: The plasma vWF level and VITRO score of the chronic hepatitis B group were (139.47±76.44) and (0.86±0.8), respectively, and the hepatitis B cirrhosis compensated group was (164.95±67.12 and 1.44±1.14), respectively. Hepatitis cirrhosis decompensated group were (317.48±103.32 and 6.81±4.98), respectively; plasma vWF level and VITRO score increased with the progression of HBV infection, and the difference was statistically significant (F=133.669,P=0.000F=137.598,P=0.000).The plasma vWF level and VITRO score in patients with hepatitis B cirrhosis were (185.65±85.07 and 2.3±2.37) in the Child-Pugh A group, (304.74±105.81 and 6.37±5.19) in the B grade group, and (369.48±73.238.28±5.38) in the C grade group; plasma vWF level and VITRO score in patients with hepatitis B cirrhosis increased with the increase of Child-Pugh grade, and the difference was statistically significant (F=60.236, P=0.000F=32.854, P=0.000). The area under the curve (AUC) of plasma vWF level and VITRO score for diagnosing the decompensated stage of hepatitis B cirrhosis were 0.897 [95% confidence interval (CI): 0.855-0.940, P＜0.01], 0.949 [95% CI: 0.916-0.982, P＜0.01). When the vWF level and VITRO score were taken as cut-off values of 238.5% and 1.65, respectively, the sensitivity of diagnosing the decompensated stage of hepatitis B cirrhosis was 79.5% and 94.3%, the specificity was 92.3% and 87.7%, and the positive predictive value was 80.5% and 94.3%, the negative predictive value was 91.9% and 97.5%, and the diagnostic accuracy was 88.6% and 89.3%. Among the patients with decompensated hepatitis B cirrhosis, the level of vWF in the group with gastrointestinal bleeding (367.24±68.29)% was significantly higher than that in the group without gastrointestinal bleeding (286.15±109.69)%, and the difference was statistically significant (P＜0.001) The VITRO score of the group with gastrointestinal bleeding (9.12±5.4) was significantly higher than that of the group without gastrointestinal bleeding (5.36±4.13), and the difference was statistically significant (P＜0.01). The vWF level in the spontaneous peritonitis group was (341.73±87.92)% higher than that in the non-spontaneous peritonitis group (296.32±111.74)%, and the difference was statistically significant (P＜0.05). There was no statistical difference in VITRO score between the two groups. significance. Conclusion: Plasma vWF level and VITRO score can evaluate the progression of liver disease and the degree of decompensation of liver cirrhosis in patients with HBV infection, and have a predictive effect on various complications after decompensation of liver cirrhosis, and have certain guiding significance for early intervention measures.

Значення фактора Віллебранда як предиктора ризику розвитку остеопоротичного процесу в жінок із гіпотиреозом

У проведеному дослідженні встановлено значення фактора Віллебранда як маркера ендотеліальної дисфункції у формуванні та прогнозуванні ризику розвитку остепоротичного процесу в жінок із гіпотиреозом. У жінок постменопаузального періоду з гіпотиреозом спостерігається вірогідне збільшення концентрації фактора Віллебранда при остеопенії в поперековому відділі хребта. Високі концентрації фактора Віллебранда у жінок із гіпотиреозом слід розглядати як предиктор ризику розвитку остеопоротичного процесу. Підвищений рівень С-реактивного білка належить до несприятливих прогностичних ознак щодо зниження мінеральної щільності кісткової тканини у хворих на первинний гіпотиреоз.

Plasma ADAMTS13 and von Willebrand factor in diagnosis and prediction of prognosis in pulmonary arterial hypertension.

To improve outcome in pulmonary arterial hypertension, earlier diagnosis and better prognostic assessments are required. We aimed to investigate the diagnostic and prognostic potential of plasma proteins related to pathways recognized in pulmonary arterial hypertension including coagulation, inflammation, and metabolism. Forty-two proteins were analysed with proximity extension assay from plasma of 20 healthy controls and 150 patients, including (pulmonary arterial hypertension, n = 48, whereof 33 also during early treatment follow-ups); chronic thromboembolic pulmonary hypertension (CTEPH, n = 20); pulmonary hypertension (PH) due to heart failure (HF) with preserved ejection fraction (HFpEF-PH, n = 31); PH due to HF with reduced ejection fraction (HFrEF-PH, n = 36); and HF without PH (Dyspnoea/HF-non-PH, n = 15). Patients’ haemodynamics were assessed by right heart catheterization. Plasma ADAMTS13 in incident pulmonary arterial hypertension was lower compared to the healthy controls (p = 0.055), as well as CTEPH (p < 0.0001), HFrEF-PH (p < 0.0001), HFrEF-PH (p < 0.0001), and Dyspnoea/HF-non-PH (p < 0.0001). Adjusted for age and sex, ADAMTS13 discriminated pulmonary arterial hypertension from the other disease groups with an AUC of 0.91 (sensitivity = 87.5%, and specificity = 78.4%). Higher plasma von Willebrand factor was associated with worse survival (log-rank p = 0.0029), and a higher mortality rate (adjusted hazard ratio 1.002, 95% confidence interval 1–1.004; p = 0.041). Adjusted for age, sex, and combined with the ESC/ERS risk score, von Willebrand factor predicted mortality (median follow-up 3.6 years) in pulmonary arterial hypertension with an AUC of 0.94 (sensitivity = 81.3%, and specificity=93.8%). ADAMTS13 may be a promising biomarker for early detection of PAH and von Willebrand factor as a candidate prognostic biomarker. The putative additional value of von Willebrand factor to the European multiparametric risk assessment strategy remains to be elucidated.

Prognostic value of von Willebrand factor in adult patients with congenital heart disease

Objectivesvon Willebrand factor (vWF) has prognostic value in patients with heart failure (HF) and in those with liver disease. Liver congestion, due to right-sided HF (RHF), is one of the...

Association of Blood Type With Postsurgical Mucosal Bleeding in Pediatric Patients Undergoing Tonsillectomy With or Without Adenoidectomy

Blood type (BT) O has been identified as a risk factor for bleeding complications, while non-O BTs may increase risk for thromboembolic events. Limited data are available in children undergoing tonsillectomy with or without adenoidectomy. To determine whether BT O is associated with hemorrhage after tonsillectomy with or without adenoidectomy. Retrospective cohort study of patients younger than 22 years who underwent tonsillectomy with or without adenoidectomy at a single institution between January 1, 2008, and August 7, 2017. Statistical analysis was performed from November 2017 to January 2019. Prevalence of hemorrhage following surgery was defined as any bleeding requiring cauterization up to 1 month after the procedure. Data on sex, age, von Willebrand disease (VWD) status, BT, white blood cell counts, and platelet counts closest to date of surgery were collected from an electronic medical record system, and the association of these factors with hemorrhage following surgery was investigated. A total of 14 951 pediatric patients (median [range] age, 5.6 [0.8-21.9] years; 6956 [46.5%] female) underwent tonsillectomy with or without adenoidectomy. Prevalence of hemorrhage following the procedure was 3.9% (578 patients) for the full cohort and 2.8% (362 of 13 065) for patients with no BT identified or preprocedure VWD panel results at baseline. Children who had a BT identified and/or a VWD panel before surgery had higher bleeding rates (BT only, 14.9% [172 of 1156]; preprocedure VWD panel only, 4.6% [28 of 607]; and BT and preprocedure VWD panel, 13.0% [16 of 123]), all of which were significantly different from the baseline bleeding rate (P < .001). While the bleeding rates in children with BT O were not statistically different from those with non-O BT (14.8% and 14.6%, respectively; P > .99), mean von Willebrand factor values were statistically different (mean [SD] von Willebrand factor antigen level in O group, 86.9 [42.4] IU/dL in the O group vs 118.0 [53.8] IU/dL in the non-O group; P = .002; and mean [SD] von Willebrand factor ristocetin-cofactor in the O group, 72.2 [44.3] IU/dL vs 112.6 [68.0] IU/dL in the non-O group; P = .001). In addition, children older than 12 years had increased bleeding rates in the full cohort (8.3% vs 3.2%), in the testing-naive cohort (6.5% vs 2.3%), and in those with a preprocedure VWD panel only (13.5% vs 3.1%) compared with children aged 12 years or younger. Type O blood was not a risk factor associated with hemorrhage after tonsillectomy with or without adenoidectomy despite lower baseline von Willebrand factor antigen and von Willebrand factor ristocetin-cofactor values in children with BT O vs those with non-O BT in our study cohort. No association was found between VWD status and bleeding, and there was no difference in VWD panel values in those who experienced hemorrhage vs those who did not within BT groups. Further studies elucidating the utility of von Willebrand factor values for children undergoing tonsillectomy with or without adenoidectomy are needed.

Hemostasis in elderly patients with human immunodeficiency virus (HIV) infection-Cross-sectional study.

Introduction: Aging and chronic HIV infection are clinical conditions that share the states of inflammation and hypercoagulability. The life expectancy of the world population has increased in the last decades, bringing as complications the occurrence of diseases that undergoing metabolic, bone, cardiological, vascular and neurological alterations. HIV-infected patients experience these changes early and are living longer due to the success of antiretroviral therapy. The objectives of this study was to evaluate some changes in the plasma hemostatic profile of 115 HIV-reactive elderly individuals over 60 years old in the chronic phase of infection, and compare with 88 healthy uninfected elderly individuals. Plasma determinations of D-dimers, Fibrinogen, von Willebrand Factor, Antithrombin, Prothrombin Time, Activated Partial Thromboplastin Time, and platelet count were performed. In the HIV-reactive group, these variables were analyzed according to viral load, protease inhibitor use and CD4+ T lymphocyte values. After adjusted values for age and sex, the results showed higher levels of Antithrombin (103%; 88%, p = 0.0001) and Prothrombin Time activities (92.4%; 88.2%, p = 0.019) in the HIV group compared to the control group. We observed higher values of Fibrinogen in protease inhibitor users in both the male (p = 0.043) and female (p = 0.004) groups, and in the female HIV group with detected viral load (p = 0.015). The male HIV group with a CD4+ count> 400 cells / mm3 presented higher von Willebrand Factor values (p = 0.036). D-Dimers had higher values in the older age groups (p = 0.003; p = 0.042, respectively). Conclusion: Our results suggest that the elderly with chronic HIV infection with few comorbidities had a better hemostatic profile than negative control group, reflecting the success of treatment. Protease inhibitor use and age punctually altered this profile.