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1
Scharrer, I. "Women with von Willebrand disease." Hämostaseologie 24, no. 01 (2004): 44–49. http://dx.doi.org/10.1055/s-0037-1619605.
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SummaryThe clinical presentation of VWD shows sex-related differences of symptoms. In women the most typical symptoms are menorrhagia, bleeding during and after delivery or abortion and bleeding in connection with caesarean section or gynaecological surgery. Menorrhagia is one of the most common symptoms presented to gynaecologists. In 7-20% of menorrhagia the underlying cause is VWD, in our cohort of 185 women with menorrhagia the prevalence of VWD was even 32%. On the other hand in women with VWD menorrhagia with onset at the menarche can be found in 60-93%, influencing substantially their morbidity and quality of life. During pregnancy women with mild VWD experience a decrease of bleeding tendency due to an increase of endogenous VWF. But as the VWF concentration drops rapidly after delivery, the post-partum period is often associated with significant bleeding complications. In severe forms of VWD the bleeding risk is high during delivery and postpartum period. Laboratory monitoring and therapeutical measures should be continued for 8-10 days after delivery. During menopause the clinical situation improves for most of the women with mild or moderate VWD.
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Arif, Mansyur. "Laboratory Diagnosis of von Willebrand's Disease." Indonesian Biomedical Journal 1, no. 3 (December 1, 2009): 57. http://dx.doi.org/10.18585/inabj.v1i3.100.
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von Willebrand's disease (vWD) is an autosomally inherited bleeding disorder caused by a deficiency or abnormality of von Willebrand factor (vWF). vWF is a multimeric adhesive protein that plays an important role in primary hemostasis by promoting platelet adhesion to the subendothelium at the sites of vascular injury. It is also the carrier of factor VIII (FVIII), thus indirectly contributing to the coagulation process. Bleeding symptoms are usually mucocutaneous and postsurgical with varying severity. The diagnosis of vWD requires a personal and family history of bleeding and confirmation by laboratory analysis involving vWF antigen level, vWF ristocetin cofactor, FVIII activity, ristocetin-induced platelet aggregation, and vWF multimer analysis.KEYWORDS: von Willebrand's disease, von Willebrand factor
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Sanders, Yvonne V., Dafna Groeneveld, Karina Meijer, Karin Fijnvandraat, Marjon H. Cnossen, Johanna G. van der Bom, M. Coppens, et al. "von Willebrand factor propeptide and the phenotypic classification of von Willebrand disease." Blood 125, no. 19 (May 7, 2015): 3006–13. http://dx.doi.org/10.1182/blood-2014-09-603241.
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Key Points VWFpp discriminates between type 3 VWD patients and severe type 1 VWD patients with very low VWF levels. The pathophysiological mechanisms of all types of VWD can be defined by the combined ratios of VWFpp/VWF:Ag and FVIII:C/VWF:Ag.
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Varma, Subhash, Pankaj Malhotra, Jasmina Ahluwalia, Aashima Arora, Rashmi Bagga, and Akanksha Jangid. "Von Willebrand Disease in Pregnancy." Journal of Postgraduate Medicine, Education and Research 48, no. 3 (2014): 157–58. http://dx.doi.org/10.5005/jp-journals-10028-1123.
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ABSTRACT Von Willebrand disease (vWD) is the most common inherited bleeding disorder. It is due to deficiency of von Willebrand factor (vWF) which may be either quantitative or qualitative. There are 3 types of vWD out of which Type III is the rarest but the most severe. We report a 27 years second gravida diagnosed with vWD in her index pregnancy. Though her antenatal period was uneventful, she developed complications in the perioperative period following a caesarean section. However, with a multidisciplinary team effort, the maternal and fetal outcome were favourable. How to cite this article Bagga R, Jangid A, Gainder S, Malhotra P, Varma S, Ahluwalia J, Arora A. Von Willebrand Disease in Pregnancy. J Postgrad Med Edu Res 2014;48(3):157-158.
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Trossaërt, Marc, Catherine Ternisien, Armelle Lefrancois, Laura Llopis, Jenny Goudemand, Marianne Sigaud, Marc Fouassier, and Claudine Caron. "Evaluation of an Automated von Willebrand Factor Activity Assay in von Willebrand Disease." Clinical and Applied Thrombosis/Hemostasis 17, no. 6 (August 19, 2010): E25—E29. http://dx.doi.org/10.1177/1076029610379848.
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We evaluated the use of the turbidimetric HemosIL von Willebrand Factor (VWF) Activity assay (VWF:Act) on the STA-R automated coagulometer (Stago, Asnières, France) for the diagnosis of von Willebrand disease (VWD). For this, we prospectively screened 268 patients. As a second part, we retrospectively assayed 111 patients with well-defined VWD subtype. In the first prospective study, we demonstrate that in most cases of VWD, VWF ristocetin cofactor activity (VWF:RCo) and VWF:Act are highly correlated but that they both cannot be considered a good screening assay when used alone, since they could miss about 25% of VWF abnormalities. However, the association of VWF:Act analysis and the Platelet Function Analyzer-100 (PFA-100) test constitutes an excellent screening strategy. In our second retrospective study concerning VWD subtypes, VWF:RCo and VWF:Act were well correlated but could be very discrepant, especially for some cases of type 2M VWD. We consider that VWF:RCo remains the “reference assay” for VWD subtype classification.
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Stufano, Francesca, Marco Boscarino, Paolo Bucciarelli, Luciano Baronciani, Alberto Maino, Giovanna Cozzi, and Flora Peyvandi. "Evaluation of the Utility of von Willebrand Factor Propeptide in the Differential Diagnosis of von Willebrand Disease and Acquired von Willebrand Syndrome." Seminars in Thrombosis and Hemostasis 45, no. 01 (June 18, 2018): 036–42. http://dx.doi.org/10.1055/s-0038-1660481.
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AbstractAn increased von Willebrand factor propeptide (VWFpp) to VWF antigen (VWF:Ag) ratio (VWFpp/VWF:Ag) indicates an enhanced clearance of VWF. This finding has been described in von Willebrand disease (VWD) and in acquired von Willebrand syndrome (AVWS). A distinction between these two diseases, one congenital and the other acquired, is primarily based on family and personal history of bleeding. However, if this information is scanty, the diagnosis might be challenging due to the lack of an effective diagnostic biomarker. In this cross-sectional study, we assessed the ability of VWFpp/VWF:Ag for the differential diagnosis between VWD and AVWS. VWFpp/VWF:Ag was measured in a group of 153 patients (125 with VWD and 28 with AVWS). Most patients with AVWS and VWD showed an increased VWFpp/VWF:Ag, although to variable degrees. A marked increase of VWFpp/VWF:Ag was mainly associated with the diagnosis of AVWS and VWD type 1 Vicenza. A receiver operating characteristic curve was used to identify the optimal cutoff of VWFpp/VWF:Ag for discrimination of patients with a modestly increased (most VWD cases) versus those with a markedly increased clearance (AVWS and VWD type 1 Vicenza), and this cutoff was identified at the value of 3.9 (sensitivity: 0.70, specificity: 0.97). The ROC curve sorting from a logistic model containing VWFpp/VWF:Ag, age, and sex had an area under the curve (AUC) of 0.88 (95% confidence interval: 0.80–0.95). A subsequent molecular evaluation discriminated VWD type 1 Vicenza from AVWS. In conclusion, VWFpp/VWF:Ag appears helpful to discriminate patients with a markedly increase VWF clearance (AVWS or VWD type 1 Vicenza) from those with a modestly increased clearance (most VWD patients).
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Periayah, Mercy Halleluyah, Ahmad Sukari Halim, Arman Zaharil Mat Saad, Nik Soriani Yaacob, and Faraizah Abdul Karim. "Report on von Willebrand Disease in Malaysia." Open Access Macedonian Journal of Medical Sciences 4, no. 1 (February 29, 2016): 112–17. http://dx.doi.org/10.3889/oamjms.2016.030.
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BACKGROUND: Von Willebrand disease (vWD) is an inherited hemostatic disorder that affects the hemostasis pathway. The worldwide prevalence of vWD is estimated to be 1% of the general population but only 0.002% in Malaysia.AIM: Our present paper has been written to disclose the statistical counts on the number of vWD cases reported from 2011 to 2013.MATERIAL AND METHODS: This article is based on sociodemographic data, diagnoses and laboratory findings of vWD in Malaysia. A total of 92 patients were reported to have vWD in Malaysia from 2011 to 2013.RESULTS: Sociodemographic-analysis revealed that 60% were females, 63% were of the Malay ethnicity, 41.3% were in the 19-44 year old age group and 15.2% were from Sabah, with the East region having the highest registered number of vWD cases. In Malaysia, most patients are predominately affected by vWD type 1 (77.2%). Factor 8, von Willebrand factor: Antigen and vWF: Collagen-Binding was the strongest determinants in the laboratory profiles of vWD.CONCLUSION: This report has been done with great interest to provide an immense contribution from Malaysia, by revealing the statistical counts on vWD from 2011-2013.
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Lavin, Michelle, and James S. O’Donnell. "New treatment approaches to von Willebrand disease." Hematology 2016, no. 1 (December 2, 2016): 683–89. http://dx.doi.org/10.1182/asheducation-2016.1.683.
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Abstract von Willebrand disease (VWD) is the commonest inherited bleeding disorder and results from either a quantitative or qualitative deficiency in the plasma glycoprotein von Willebrand factor (VWF). Recent large cohort studies have significantly enhanced our understanding of the molecular mechanisms involved in the pathogenesis of VWD. In contrast, however, there have been relatively few advances in the therapeutic options available for the treatment of bleeding in patients with VWD. Established treatment options include tranexamic acid, 1-deamino-8-d-arginine vasopressin (DDAVP), and plasma-derived VWF concentrates. In addition, a recombinant VWF has also recently been developed. In this review, we focus on how recent insights into the clinical and molecular aspects underpinning VWD are already beginning to influence treatment in the clinic. For example, a number of different bleeding assessment tools (BATs) have been developed to objectively assess bleeding symptoms in patients with VWD. Interestingly, however, these BAT scores may also have an important role to play in predicting bleeding risk in VWD. Furthermore, recent studies have demonstrated that enhanced VWF clearance plays a critical role in the etiology of both type 1 and type 2 VWD. These findings have direct translational relevance with respect to the use of DDAVP in patients with VWD. As understanding of the mechanisms involved in VWD pathogenesis continues to advance, novel treatment options are likely to emerge. Critically, however, large adequately powered and stratified clinical trials will be required to address the outstanding questions that remain regarding VWD treatment optimization.
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Henniker, Anthony, David Facey, Mark Hertzberg, and Emmanuel Favaloro. "Discrimination of von Willebrands Disease (VWD) Subtypes: Direct Comparison of von Willebrand Factor:Collagen Binding Assay (VWF:CBA) with Monoclonal Antibody (MAB) Based VWF-capture Systems." Thrombosis and Haemostasis 84, no. 10 (2000): 541–47. http://dx.doi.org/10.1055/s-0037-1614064.
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SummaryDiscrimination of von Willebrand’s Disease (VWD) subtypes is important since it influences management. Qualitative [ie Type 2A, 2B, 2M] defects exhibit von Willebrand factor (VWF) discordance and give high VWF:Ag to VWF:’activity’ ratios. Classically, VWF:’activity’ is assessed using the VWF:RCof assay. The VWF:CBA is an ELISAbased VWF-functional adhesive assay which has consistently proved to be superior to VWF:RCof. A commercially available monoclonal antibody (MAB) based ELISA assay system claimed to mimic a VWF:RCof-like activity has also been recently described (‘SE’), as has the production and characterisation of a large number [n = 10] of locally generated anti-VWF MAB. In the current study, we have adapted these MAB to in-house ELISA assays to assess their utility for VWD diagnosis and subtype discrimination, and to compare them with other assay systems. Thus, the VWF:CBA, VWF:RCof by agglutination, the SE assay, and in-house MAB based assays have been directly compared for their ability to discriminate Type 1 [n = 9] from Type 2 VWD samples [phenotypes 2A and 2B; n = 11]. In summary, MAB-based systems can be used to measure VWF and confirm a diagnosis of VWD, as well as exhibiting some VWD-subtype-discriminatory capabilities. However, better evidence of VWF-discordance was usually achieved using the VWF:RCof (agglutination) assay, while the greatest degree of VWFdiscordance was consistently observed using the VWF:CBA assay. In conclusion, the VWF:CBA assay proved to offer the best diagnostic predictive tool for a Type 2 VWD defect, while MAB-based systems appear to be less effective in this regard. Abbreviations: HMW: High Molecular Weight [VWF], MAB: Monoclonal antibody (/antibodies), PNP: Pooled Normal Plasma, RIPA: Ristocetin induced platelet aggregation, VWD: von Willebrands disease (/disorder), VWF: von Willebrand Factor, VWF:Ag: von Willebrand Factor Antigen (assay), VWF:CBA: Collagen Binding [Activity] Assay for VWF, VWF:RCof: Ristocetin Cofactor Assay for VWF
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Batlle, Javier, Almudena Pérez-Rodríguez, Irene Corrales, Nina Borràs, Joana Costa Pinto, María Fernanda López-Fernández, and Francisco Vidal. "Update on Molecular Testing in von Willebrand Disease." Seminars in Thrombosis and Hemostasis 45, no. 07 (April 30, 2019): 708–19. http://dx.doi.org/10.1055/s-0039-1679922.
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AbstractDiagnosis of von Willebrand disease (VWD) depends on personal and family history of bleeding and confirmatory laboratory testing. Currently available phenotypic tests for VWD contain potential sources for error that may distort results. Despite an exponential growth of information about the von Willebrand factor gene (VWF), the role of molecular diagnosis in VWD is still controversial. Due to the complexity and high cost of conventional molecular analyses, some investigators have recommended limiting this approach to distinguish suspected type 2N VWD from hemophilia A, type 2B from platelet-type VWD, and the exploration of type 3 VWD. New genetic methodologies and approaches are becoming available, but there is still some reluctance for their implementation in VWD diagnosis. This article discusses the pros and cons of molecular testing in VWD considering the experience obtained through the multicenter project “Molecular and Clinical Profile of VWD in Spain (PCM-EVW-ES).”
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Goodeve, Anne. "Diagnosing von Willebrand disease: genetic analysis." Hematology 2016, no. 1 (December 2, 2016): 678–82. http://dx.doi.org/10.1182/asheducation-2016.1.678.
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Abstract Investigation of a patient with possible von Willebrand disease (VWD) includes a range of phenotypic analyses. Often, this is sufficient to discern disease type, and this will suggest relevant treatment. However, for some patients, phenotypic analysis does not sufficiently explain the patient’s disorder, and for this group, genetic analysis can aid diagnosis of disease type. Polymerase chain reaction and Sanger sequencing have been mainstays of genetic analysis for several years. More recently, next-generation sequencing has become available, with the advantage that several genes can be simultaneously analyzed where necessary, eg, for discrimination of possible type 2N VWD or mild hemophilia A. Additionally, several techniques can now identify deletions/duplications of an exon or more that result in VWD including multiplex ligation-dependent probe amplification and microarray analysis. Algorithms based on next-generation sequencing data can also identify missing or duplicated regions. These newer techniques enable causative von Willebrand factor defects to be identified in more patients than previously, aiding in a specific VWD diagnosis. Genetic analysis can also be helpful in the discrimination between type 2B and platelet-type VWD and in prenatal diagnosis for families with type 3.
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Seaman, Craig D., and Margaret V. Ragni. "The Effect of Age on von Willebrand Factor and Bleeding Symptoms in von Willebrand Disease." Thrombosis and Haemostasis 120, no. 08 (July 6, 2020): 1159–65. http://dx.doi.org/10.1055/s-0040-1713636.
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Abstractvon Willebrand disease (VWD) is a quantitative or qualitative defect in von Willebrand factor (VWF) resulting in mucocutaneous bleeding symptoms and hemorrhage following hemostatic challenges, such as trauma or surgery. VWD-specific therapy, DDAVP (1-desamino-8-D-arginine vasopressin) and VWF concentrates, is necessary periprocedurally to ensure adequate hemostasis. The aging VWD patient may complicate this matter. The plasma concentration of many coagulation proteins, including VWF, increases with age. While it has been established that VWF levels increase with age in a healthy population, emerging research demonstrates this occurs in certain subtypes of VWD, too. Thus, the management of periprocedural VWD-specific therapy in the aging VWD patient is problematic when VWF levels increase over time to normal, and hematologists are left with uncertainty regarding whether or not periprocedural VWD-specific therapy is still necessary. In this article, we will review the current state of the literature regarding the effect of age on VWF levels in the healthy population and VWD while exploring possible etiologies for this phenomenon. Further, we will detail how this affects bleeding symptoms and highlight what research remains to be done to optimize care in this patient population.
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Asakura, A., J. Harrison, E. Gomperts, and C. Abildgaard. "Type IIA von Willebrand disease with apparent recessive inheritance." Blood 69, no. 5 (May 1, 1987): 1419–20. http://dx.doi.org/10.1182/blood.v69.5.1419.1419.
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Abstract Type IIA von Willebrand's Disease (vWD) is the most common type II variant, and all reported cases (56 individuals in 26 families) have had autosomal dominant inheritance. An eight-year-old female with an increased bleeding tendency since infancy was found to have laboratory values typical of type IIA vWD, but her parents and siblings were asymptomatic. With the exception of uniformly decreased levels of ristocetin cofactor in relation to von Willebrand factor antigen, the results of family studies were normal including the presence of large multimeric forms of von Willebrand factor antigen. These findings are consistent with the propositus having the homozygous state of an autosomal recessive trait. Desmopressin infusion in the propositus was followed by a significant increase of factor VIII coagulant and von Willebrand factor antigen but a limited change in ristocetin cofactor with no development of large multimers.
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Asakura, A., J. Harrison, E. Gomperts, and C. Abildgaard. "Type IIA von Willebrand disease with apparent recessive inheritance." Blood 69, no. 5 (May 1, 1987): 1419–20. http://dx.doi.org/10.1182/blood.v69.5.1419.bloodjournal6951419.
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Type IIA von Willebrand's Disease (vWD) is the most common type II variant, and all reported cases (56 individuals in 26 families) have had autosomal dominant inheritance. An eight-year-old female with an increased bleeding tendency since infancy was found to have laboratory values typical of type IIA vWD, but her parents and siblings were asymptomatic. With the exception of uniformly decreased levels of ristocetin cofactor in relation to von Willebrand factor antigen, the results of family studies were normal including the presence of large multimeric forms of von Willebrand factor antigen. These findings are consistent with the propositus having the homozygous state of an autosomal recessive trait. Desmopressin infusion in the propositus was followed by a significant increase of factor VIII coagulant and von Willebrand factor antigen but a limited change in ristocetin cofactor with no development of large multimers.
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Rodeghiero, Francesco, Giancarlo Castaman, and Alberto Tosetto. "How I treat von Willebrand disease." Blood 114, no. 6 (August 6, 2009): 1158–65. http://dx.doi.org/10.1182/blood-2009-01-153296.
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Abstract Recent multicenter studies have clarified the molecular basis underlying the different von Willebrand disease (VWD) types, all of which are caused by the deficiency and/or abnormality of von Willebrand factor (VWF). These studies have suggested a unifying pathophysiologic concept. The diagnosis of VWD, remains difficult because its clinical and laboratory phenotype is very heterogeneous and may overlap with normal subjects. Stringent criteria are therefore required for a clinically useful diagnosis. In this paper, we delineate a practical approach to the diagnosis and treatment of VWD. Our approach is based on the critical importance of a standardized bleeding history that has been condensed into a final bleeding score and a few widely available laboratory tests, such as VWF ristocetin cofactor activity, VWF antigen and factor VIII. This approach would help identify those subjects who will probably benefit from a diagnosis of VWD. The next step involves performing a trial infusion with desmopressin in all patients who fail to exhibit an enhanced responsiveness to ristocetin. On the basis of these results and through a series of illustrative examples, the clinician will be able to select the best approach for the optimal management of VWD, according to the patient's characteristics and clinical circumstances.
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Riddel, James P., and Bradley E. Aouizerat. "Genetics of von Willebrand Disease Type 1." Biological Research For Nursing 8, no. 2 (October 2006): 147–56. http://dx.doi.org/10.1177/1099800406286492.
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The most common form of von Willebrand disease (VWD) is reported to be type 1, accounting for as much as 80% of reported cases. With prevalence estimates as high as 1.6% in the general population, upwards of 4.5 million Americans may be affected. Unfortunately, VWD type 1 is also the most difficult type to diagnose. Despite the continuing progress in defining the genetic lesions responsible for VWD types 2 and 3, identification of the genetic determinants of VWD type 1 remains elusive. Herein the phenomenon known as VWD is summarized, the challenges associated with the diagnosis of type 1 VWD are described, and the role of genetic research in meeting these challenges is explored. The authors identify key gaps in the current genetics literature and suggest new avenues for future research. Lastly, they explore the role of nurses in this research and clinical endeavor. To the authors'knowledge, this review is the first to address these complex issues in nursing research.
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Casonato, Alessandra, Elena Pontara, Francesca Sartorello, Maria Grazia Cattini, Maria Teresa Sartori, Roberto Padrini, and Antonio Girolami. "Reduced von Willebrand factor survival in type Vicenza von Willebrand disease." Blood 99, no. 1 (January 1, 2002): 180–84. http://dx.doi.org/10.1182/blood.v99.1.180.
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Type Vicenza variant of von Willebrand disease (VWD) is characterized by a low plasma von Willebrand factor (VWF) level and supranormal VWF multimers. Two candidate mutations, G2470A and G3864A at exons 17 and 27, respectively, of the VWF gene were recently reported to be present in this disorder. Four additional families, originating from northeast Italy, with both mutations of type Vicenza VWD are now described. Like the original type Vicenza subjects, they showed a mild bleeding tendency and a significant decrease in plasma VWF antigen level and ristocetin cofactor activity but normal platelet VWF content. Unlike the original patients, ristocetin-induced platelet aggregation was found to be normal. Larger than normal VWF multimers were also demonstrated in the plasma. Desmopressin (DDAVP) administration increased factor VIII (FVIII) and VWF plasma levels, with the appearance of even larger multimers. However, these forms, and all VWF oligomers, disappeared rapidly from the circulation. The half-life of VWF antigen release and of elimination was significantly shorter than that in healthy counterparts, so that at 4 hours after DDAVP administration, VWF antigen levels were close to baseline. Similar behavior was demonstrated by VWF ristocetin cofactor activity and FVIII. According to these findings, it is presumed that the low plasma VWF levels of type Vicenza VWD are mainly attributed to reduced survival of the VWF molecule, which, on the other hand, is normally synthesized. In addition, because normal VWF-platelet GPIb interaction was observed before or after DDAVP administration, it is proposed that type Vicenza VWD not be considered a 2M subtype.
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Meiring, Muriel, Philip N. Badenhorst, and Mareli Kelderman. "Laboratory Diagnosis of von Willebrand Disease." European Oncology & Haematology 03, no. 01 (2009): 33. http://dx.doi.org/10.17925/eoh.2009.03.1.33.
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von Willebrand disease (VWD) is a bleeding disorder caused by either quantitative (type 1 and 3) or qualitative (type 2) defects of von Willebrand factor (VWF). No single available test provides appropriate information about the various functions of VWF, and the laboratory diagnosis of VWD is based on a panel of tests, including the measurement of factor VIII coagulant activity (FVIIIC), VWF antigen levels (VWF:Ag), VWF activity as measured by the ristocetin co-factor activity (VWF:RCo), the collagen-binding activity of VWF (VWF:CB), VWF multimer analysis, ristocetininduced platelet agglutination (RIPA), the factor-VIII-binding assay of plasma VWF and VWF propeptide levels. Due to the heterogeneity of VWF defects and the variables that interfere with VWF levels, a correct diagnosis of types and subtypes may sometimes be difficult, but is very important for therapy. Furthermore, the RCo assay and the RIPA test are based on platelet agglutination in reaction with the non-physiological antibiotic ristocetin. These tests also have low sensitivity and are difficult to standardise. Therefore, several analyses (tests) are required to diagnose VWD and it is important to be aware of the pitfalls to which these tests are subjected in terms of the diagnosis. In this article, the laboratory diagnosis of patients with type 1, 2A, 2B, 2M, 2N and 3 VWD will be explained by using a modified algorithm that was first proposed by the guidelines for diagnosis and treatment of VWD in Italy.
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Denis, Cécile V., Sophie Susen, and Peter J. Lenting. "von Willebrand disease: what does the future hold?" Blood 137, no. 17 (April 29, 2021): 2299–306. http://dx.doi.org/10.1182/blood.2020008501.
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Abstract von Willebrand disease (VWD) is characterized by its heterogeneous clinical manifestation, which complicates its diagnosis and management. The clinical management of VWD has remained essentially unchanged over the last 30 years or so, using von Willebrand factor (VWF) concentrates, desmopressin, and anti–fibrinolytic agents as main tools to control bleeding. This is in contrast to hemophilia A, for which a continuous innovative path has led to novel treatment modalities. Despite current VWD management being considered effective, quality-of-life studies consistently reveal a higher than anticipated burden of VWD on patients, which is particularly true for women. Apparently, despite our perceived notion of current therapeutic efficiency, there is space for innovation with the goal of reaching superior efficacy. Developing innovative treatments for VWD is complex, especially given the heterogeneity of the disease and the multifunctional nature of VWF. In this perspective article, we describe several potential strategies that could provide the basis for future VWD treatments. These include genetic approaches, such as gene therapy using dual-vector adenoassociated virus and transcriptional silencing of mutant alleles. Furthermore, protein-based approaches to increase factor FVIII levels in VWD-type 3 or 2N patients are discussed. Finally, antibody-based options to interfere with VWF degradation (for congenital VWD-type 2A or acquired von Willebrand syndrome-type 2A) or increase endogenous VWF levels (for VWD-type 1) are presented. By highlighting these potential strategies, we hope to initiate an innovative path, which ultimately would allow us to better serve VWD patients and their specific needs.
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Takahashi, Hoyu, and Akira Shibata. "Agglutination of Platelet-Type von Willebrand’s Disease Platelets by Bovine von Willebrand Factor." Thrombosis and Haemostasis 53, no. 02 (1985): 204–7. http://dx.doi.org/10.1055/s-0038-1661274.
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SummaryIt has been shown that platelets from patients with platelet- type von Willebrand’s disease (vWD) agglutinate upon the addition of human von Willebrand factor (vWF) in the absence of ristocetin or botrocetin, suggesting that platelet membrane receptors for human vWF is abnormal. The present work reports the platelet agglutinability on stimulation with bovine vWF in platelet-type vWD. Platelets in patient platelet-rich plasma or washed platelet suspensions and patient platelets treated with formalin agglutinated in the presence of markedly lower concentrations of bovine vWF than those required for normal platelets. This finding provides additional evidence that platelet-type vWD platelets have abnormal expression of binding sites for vWF on their surface, and supports that platelet receptors for bovine vWF are identical or very close to those for human vWF.
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O'Donnell, James S. "Toward Personalized Treatment for Patients with Low von Willebrand Factor and Quantitative von Willebrand Disease." Seminars in Thrombosis and Hemostasis 47, no. 02 (February 26, 2021): 192–200. http://dx.doi.org/10.1055/s-0041-1722864.
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AbstractThe biological mechanisms involved in the pathogenesis of type 2 and type 3 von Willebrand disease (VWD) have been studied extensively. In contrast, although accounting for the majority of VWD cases, the pathobiology underlying partial quantitative VWD has remained somewhat elusive. However, important insights have been attained following several recent cohort studies that have investigated mechanisms in patients with type 1 VWD and low von Willebrand factor (VWF), respectively. These studies have demonstrated that reduced plasma VWF levels may result from either (1) decreased VWF biosynthesis and/or secretion in endothelial cells and (2) pathological increased VWF clearance. In addition, it has become clear that some patients with only mild to moderate reductions in plasma VWF levels in the 30 to 50 IU/dL range may have significant bleeding phenotypes. Importantly in these low VWF patients, bleeding risk fails to correlate with plasma VWF levels and inheritance is typically independent of the VWF gene. Although plasma VWF levels may increase to > 50 IU/dL with progressive aging or pregnancy in these subjects, emerging data suggest that this apparent normalization in VWF levels does not necessarily equate to a complete correction in bleeding phenotype in patients with partial quantitative VWD. In this review, these recent advances in our understanding of quantitative VWD pathogenesis are discussed. Furthermore, the translational implications of these emerging findings are considered, particularly with respect to designing personalized treatment plans for VWD patients undergoing elective procedures.
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Ginsburg, David. "Molecular Genetics of von Willebrand Disease." Thrombosis and Haemostasis 82, no. 08 (1999): 585–91. http://dx.doi.org/10.1055/s-0037-1615884.
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IntroductionVon Willebrand disease (vWD) is a common inherited bleeding disorder that is notable for a high degree of variability in clinical presentation and the considerable heterogeneity of its molecular basis. Confusion about the genetic origin of this disorder has existed since its original description by Eric von Willebrand in 1926.1 Dr. von Willebrand coined the term “pseudohemophilia” to describe the disease in the original pedigree. Though it resembled the bleeding diathesis of hemophilia, von Willebrand also noted findings suggesting an abnormality in platelet function. The severity of bleeding in this family varied widely from mild bleeding to severe hemorrhage, the latter resulting in the death of the proband at the time of her fourth menstrual period.Von Willebrand incorrectly characterized the inheritance pattern in the original Åland Island pedigree as X-linked dominant, because of the apparent greater frequency of the disease in female patients. Now, it is recognized that the greater frequency was largely by chance and due to increased penetrance related to the hemostatic stresses of menstruation and pregnancy. Nonetheless, von Willebrand clearly distinguished the inheritance pattern of vWD from that of classic hemophilia. It is now known that vWD is due to either quantitative or qualitative defects in von Willebrand factor (vWF), encoded by a gene on chromosome 12, whereas hemophilia is due to mutations in the factor VIII gene on the X chromosome.2
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Park, Jeong Jin, Chang-Hoon Kim, Jeung-Gweon Lee, and Hyung-Ju Cho. "Von-Willebrand Disease Presenting as Intractable Epistaxis after Nasal Polypectomy." Case Reports in Otolaryngology 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/902071.
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Von-Willebrand disease (VWD) is one of the platelet dysfunction disorders that results from a deficiency of Von-Willebrand factor, which is essential for hemostasis. VWD patients typically have normal laboratory results on screening for bleeding disorders. To suspect and diagnose VWD, a careful review of past medical history and laboratory tests is critical. A 59-year-old male patient presented with intractable nasal bleeding after nasal polypectomy. The bleeding was controlled by platelet transfusion, and he was later diagnosed with VWD.
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Saccullo, Giorgia, and Mike Makris. "Prophylaxis in von Willebrand Disease: Coming of Age?" Seminars in Thrombosis and Hemostasis 42, no. 05 (June 2, 2016): 498–506. http://dx.doi.org/10.1055/s-0036-1581106.
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Although in most cases von Willebrand disease (VWD) is a mild disorder, a subgroup of patients experience frequent bleeding. In contrast to severe hemophilia in which prophylaxis is the accepted standard of care, this is less frequently used in VWD. Most type 1 VWD patients can be adequately managed with episodic desmopressin and tranexamic acid. In patients with more severe disease, especially those with type 3 VWD, joint bleeds, epistaxis, menorrhagia, and gastrointestinal bleeding are problematic and usually require treatment with von Willebrand factor/factor VIII (VWF/FVIII) concentrate. While in the past these patients were managed with on-demand VWF/FVIII concentrate, several recent reports have demonstrated the value of prophylactic treatment. Despite some uncertainties about the economic impact of treatment of severe VWD, prophylaxis with VWF concentrate should now be considered as the standard of care for the more severe end of the spectrum of affected individuals. The recent introduction of recombinant VWF concentrate is likely to improve the acceptability of prophylaxis in VWD.
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Zolkova, J., J. Sokol, T. Simurda, L. Vadelova, Z. Snahnicanova, D. Loderer, M. Dobrotova, et al. "The Importance and Complications of Sequencing of Von Willebrand Gene in Von Willebrand Disease." Acta Medica Martiniana 19, no. 1 (April 1, 2019): 5–11. http://dx.doi.org/10.2478/acm-2019-0001.
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Abstract Genetic testing in patients with von Willebrand disease completes phenotypic testing with an aim to confirm the von Willebrand factor defect at a molecular level. Structure of the VWF gene was described 30 years ago; since then a large number of mutations leading to VWD have been described in this gene. Thanks to describing these mechanisms it is possible to understand the pathogenesis of the most common congenital bleeding disorder. In the Slovak Republic genetic testing is still not a routine part of VWD diagnostics. The National Center of Hemostasis and Thrombosis in Martin is the first department in Slovakia which has begun genetic testing of patients with VWD. Sequencing of the VWF gene has many limitations which are referred in more details within this article. Therefore, we decided to use the methods of new generation sequencing in combination with Sanger sequencing. We believe that soon we will have the first results which will help us to identify the possible cause of VWD in these patients.
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Franchini, Massimo, and Pier Mannucci. "Alloantibodies in von Willebrand Disease." Seminars in Thrombosis and Hemostasis 44, no. 06 (November 17, 2017): 590–94. http://dx.doi.org/10.1055/s-0037-1607440.
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Abstractvon Willebrand disease (VWD), the most commonly known inherited bleeding disorder, is caused by a partial (type 1) or total (type 3) deficiency or dysfunction (type 2) of von Willebrand factor (VWF). Its management encompasses the prevention or treatment of bleeding by raising endogenous VWF levels using a synthetic agent, such as desmopressin, or providing exogenous VWF concentrates. The development of inhibitory alloantibodies against VWF is a rare but often severe complication encountered during the treatment of type 3 VWD, which is associated with a lack of hemostatic response to infused VWF concentrates and more rarely with allergic, even anaphylactic, reactions. This narrative review will focus on the characteristics of such alloantibodies and their management, which can be very challenging for physicians operating at hemophilia treatment centers.
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Kruse-Jarres, Rebecca, and Jill M. Johnsen. "How I treat type 2B von Willebrand disease." Blood 131, no. 12 (March 22, 2018): 1292–300. http://dx.doi.org/10.1182/blood-2017-06-742692.
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Abstract Type 2B von Willebrand disease (VWD) is an inherited bleeding disorder caused by changes in von Willebrand factor (VWF) that enhance binding of VWF to GPIb on platelets. Although this disorder is seemingly well defined because of this single molecular defect, in reality type 2B VWD is a clinically heterogeneous disorder that can be difficult to identify and manage. Diagnostic criteria include a history of mucocutaneous bleeding, laboratory studies showing enhanced VWF binding of platelets and/or a 2B VWD genetic variant, and a family history consistent with autosomal dominant inheritance. Thrombocytopenia, although not always present, is common and can be exacerbated by physiologic stressors such as pregnancy. The mainstay of therapy for type 2B VWD is VWF replacement therapy. Adjunct therapies useful in other types of VWD, such as antifibrinolytics, are also used in type 2B VWD. 1-Desamino-8-d-arginine vasopressin (DDAVP) is controversial because of exacerbation of thrombocytopenia, but is, in practice, sometimes used for minor bleeding. Here we review the available evidence and provide 3 clinical cases to illustrate the intricacies of diagnosing type 2B VWD to describe the response to DDAVP and to review complexities and management during pregnancy.
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Sharma, Ruchika, and Sandra L. Haberichter. "New advances in the diagnosis of von Willebrand disease." Hematology 2019, no. 1 (December 6, 2019): 596–600. http://dx.doi.org/10.1182/hematology.2019000064.
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Abstract von Willebrand disease (VWD) is the most common autosomal inherited bleeding disorder, with an estimated prevalence of 1 in 1000 individuals. VWD is classified into quantitative and qualitative forms. Diagnosis of VWD is complex and requires (1) a personal history of bleeding symptoms, (2) family history of bleeding or VWD, and (3) confirmatory laboratory testing. There are certain bleeding assessment tools to objectively measure bleeding symptoms in patients that have been shown to correlate with the diagnosis as well as the severity of VWD. Laboratory diagnosis requires at least initially a measurement of von Willebrand factor (VWF) antigen levels, VWF platelet binding activity (VWF:RCo, VWF:GPIbM, and VWF:GPIbR), and factor VIII (FVIII) activity. Additional testing to confirm the specific subtype may include VWF collagen binding activity, low-dose ristocetin VWF-platelet binding, FVIII-VWF binding, VWF multimer analysis, and VWF propeptide antigen. Recent advances have been made regarding some of these assays. Molecular testing in VWD is not found to be useful in “low VWF” or most type 1 VWD cases but may be informative in patients with severe type 1 VWD, type 1C VWD, type 2 VWD, or type 3 VWD for accurate diagnosis, genetic counseling, and appropriate treatment. The diagnostic algorithm for VWD is complex, but advances continue to be made in improving VWF functional assays and diagnostic pathways.
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Brenner, Benjamin, Tamar Stemberg, Arieh Laor, Shulamit Tavori, Ilana Tatarsky, and Naomi Lanir. "Von Willebrand Factor Antigen and Factor XI Activity Levels As Predictors of Bleeding Tendency in Israeli Patients with Von Willebrand's Disease." Clinical and Applied Thrombosis/Hemostasis 1, no. 4 (September 1995): 260–64. http://dx.doi.org/10.1177/107602969500100402.
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Previous preliminary data and case reports have suggested an association of von Willebrand's disease (vWD) with factor XI deficiency and platelet abnormalities. We have analyzed the prevalence of factor XI deficiency and thrombocytopathy in a cohort of Israeli patients with vWD. Decreased factor XI levels (<67 U/dl) were documented in 35 of 63 (36%) vWD subjects; factor XI levels were <30 U/dl in five of 60 (8%). A significant decline in ADP-induced platelet aggregation (<30% of control) was found in 48% of vWD patients. Likewise, epinephrine-induced aggregation was reduced in 41%, and collagen-induced aggregation was decreased in 7% of vWD patients. Logistic regression analysis showed that while Ivy bleeding time, ristocetin cofactor, and ristocetin-induced platelet aggregation did not predict bleeding, both von Willebrand factor antigen and factor XI activity levels predict bleeding in patients with vWD. These findings suggest that mild factor XI deficiency and thrombocytopathy are common in Israeli subjects with vWD and that associated factor XI deficiency can result in clinical bleeding in these patients. Key Words: Von Willebrand' s disease—Factor XI deficiency—Thrombocytopathy.
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Bahou, WF, EJ Bowie, DN Fass, and D. Ginsburg. "Molecular genetic analysis of porcine von Willebrand disease: tight linkage to the von Willebrand factor locus." Blood 72, no. 1 (July 1, 1988): 308–13. http://dx.doi.org/10.1182/blood.v72.1.308.bloodjournal721308.
Full textAbstract:
von Willebrand disease (vWD), one of the most common bleeding disorders in humans, is manifested as a quantitative or qualitative defect in von Willebrand factor (vWF), an adhesive glycoprotein (GP) with critical hemostatic functions. Except for the rare severely affected patient with a gene deletion as etiology of the disease, the molecular basis for vWD is not known. We studied the molecular basis for vWD in a breeding colony of pigs with a disease closely resembling the human disorder. The porcine vWF gene is similar in size and complexity to its human counterpart, and no gross gene deletion or rearrangement was evident as the pathogenesis of porcine vWD. A restriction fragment- length polymorphism (RFLP) within the porcine vWF gene was identified with the restriction endonuclease HindIII, and 22/35 members of the pedigree were analyzed for the polymorphic site. Linkage between the vWF locus and the vWD phenotype was established with a calculated LOD score of 5.3 (1/200,000 probability by chance alone), with no crossovers identified. These findings indicate that porcine vWD is due to a molecular defect within (or near) the vWF locus, most likely representing a point mutation or small insertion/deletion within the vWF gene.
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Schneppenheim, R., and J. Patzke. "Laboratory diagnosis of von Willebrand disease." Hämostaseologie 30, no. 04 (2010): 203–6. http://dx.doi.org/10.1055/s-0037-1619057.
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SummaryOver the last decade, considerable progress has been made in the laboratory diagnosis of VWD. Precise, sensitive and automated VWF : Ag assays became widely available. The VWF : RCo performance was improved to a certain degree. However, the sensitivity, precision and general availability of automated applications is not yet optimal. Nevertheless, this type of assay is still recognized as superior to other activity assays, e. g. VWF : CBA assays and antibody-binding “activity” assays, for the detection of defects in VWF function.A decision limit of either 30 or 40 IU dl-1 VWF (VWF:RCo or VWF:Ag) is recommended for a diagnosis of type 1 VWD. Type 2 VWD can be differentiated from type 1 by calculating the VWF:RCo/VWF:Ag ratio.Improved and easier to perform multimer analysis and genetic testing are beginning to facilitate the diagnosis of the VWD type 1, 2A, 2B, 2N, 2M or 3. Within type 1 or 2, a decreased VWF survival can be detected by the VWFpp assay and its ratio to VWF : Ag.A new type of VWF activity assay, based on the binding of VWF to a GPIb〈-fragment, has been developed. One assay variant does not need ristocetin as a cofactor anymore. The performance investigations presented so far are very promising. It is probable that these GPIb〈-binding assays will detect functional VWF defects as the VWF : RCo assay, but are much more sensitive and precise. Fully automated applications on routine analyzers are expected to be commercialized soon.
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Delbrück, Christiane, and Wolfgang Miesbach. "The Course of von Willebrand Factor and Factor VIII Activity in Patients with von Willebrand Disease during Pregnancy." Acta Haematologica 142, no. 2 (2019): 71–78. http://dx.doi.org/10.1159/000496820.
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Introduction: Women with von Willebrand disease (VWD) are at a higher risk of bleeding, which might affect the health of mother and child during pregnancy and the intra- and postpartum periods. This retrospective cohort study evaluates changes in the coagulation parameters von Willebrand factor antigen (VWF:Ag), von Willebrand ristocetin cofactor (VWF:RCo), and Factor VIII activity (FVIII:C) during pregnancy in patients with VWD. In total, 44 pregnancies of 38 patients were assessed (VWD type 1 n = 32, type 2A n = 3, type 2B n = 1, type 2 subtype unidentified n = 2). The patients’ median age at childbirth was 32 years (range 22–40). Results: A significant increase in coagulation parameters was found in patients with VWD type 1 (VWF:Ag, VWF:RCo, and FVIII:C p = 0.000). In the third trimester, VWF:Ag and FVIII:C normalized in all patients with VWD type 1; in 3 patients VWF:RCo remained below the normal range. Patients with VWD type 2 showed a significant increase of VWF:Ag (p = 0.003) and FVIII:C (p = 0.011), and a non-significant increase of VWF:RCo (p = 0.097). In 4 of 9 pregnancies of patients with VWD type 2, all surveyed coagulation parameters normalized until the third trimester. Conclusion: For the majority of the observed patients, the von Willebrand parameters increased during pregnancy.
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O'Brien, Lee A., Paula D. James, Maha Othman, Ergul Berber, Cherie Cameron, Colleen R. P. Notley, Carol A. Hegadorn, et al. "Founder von Willebrand factor haplotype associated with type 1 von Willebrand disease." Blood 102, no. 2 (July 15, 2003): 549–57. http://dx.doi.org/10.1182/blood-2002-12-3693.
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AbstractTo date, no dominant mutation has been identified in a significant proportion of patients with type 1 von Willebrand disease (VWD). In this study, we examined 70 families as part of the Canadian Type 1 VWD Study. The entire VWF gene was sequenced for 1 index case, revealing 2 sequence variations: intron 30 (5312—19A>C) and exon 28 at Tyr1584Cys (4751A>G). The Tyr1584Cys variation was identified in 14.3% (10 of 70) of the families and was in phase with the 5312—19A>C variation in 7 (10.0%) families. Both variants were observed in 2 of 10 UK families with type 1 VWD, but neither variant was found in 200 and 100 healthy, unrelated persons, respectively. Mean von Willebrand factor antigen (VWF:Ag), VWF ristocetin cofactor (VWF:RCo), and factor VIII coagulant activity (FVIII:C) for the index cases in these families are 0.4 U/mL, 0.36 U/mL, and 0.54 U/mL, respectively, and VWF multimer patterns show no qualitative abnormalities. Aberrant VWF splicing was not observed in these patients, and both alleles of the VWF gene are expressed as RNA. Molecular dynamic simulation was performed on a homology model of the VWF-A2 domain containing the Tyr1584Cys mutation. This showed that no significant structural changes occur as a result of the substitution but that a new solvent-exposed reactive thiol group is apparent. Expression studies revealed that the Tyr1584Cys mutation results in increased intracellular retention of the VWF protein. We demonstrate that all the families with the Tyr1584Cys mutation share a common, evolved VWF haplotype, suggesting that this mutation is ancient. This is the first report of a mutation that segregates in a significant proportion of patients with type 1 VWD.
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Franchini, Massimo, and Pier Mannuccio Mannucci. "Gastrointestinal angiodysplasia and bleeding in von Willebrand disease." Thrombosis and Haemostasis 112, no. 09 (2014): 427–31. http://dx.doi.org/10.1160/th13-11-0952.
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SummaryVon Willebrand disease (VWD), the most common genetic bleeding disorder, is characterised by a quantitative or qualitative defect of von Willebrand factor (VWF). Patients with VWD suffer from mucocutaneous bleeding, of severity usually proportional to the degree of VWF defect. In particular, gastrointestinal bleeding associated with angiodysplasia is often a severe symptom of difficult management. This review focuses on the pathophysiology, diagnosis and treatment of VWD-associated gastrointestinal angiodysplasia and related bleeding.
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Coppes, M. J., S. W. Zandvoort, C. R. Sparling, A. O. Poon, S. Weitzman, and V. S. Blanchette. "Acquired von Willebrand disease in Wilms' tumor patients." Journal of Clinical Oncology 10, no. 3 (March 1992): 422–27. http://dx.doi.org/10.1200/jco.1992.10.3.422.
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PURPOSE A prospective study was performed to determine the incidence of acquired von Willebrand disease (vWD) in children with newly diagnosed Wilms' tumor. PATIENTS AND METHODS Fifty consecutive children with newly diagnosed Wilms' tumor were evaluated. Detailed family and bleeding histories were obtained in all cases. Laboratory evaluation included measurement of the circulating platelet count, bleeding time (BT), factor VIII (FVIII) and von Willebrand factor (vWF) levels, and ristocetin cofactor (RCoF) activity. A vWF multimer analysis was obtained in all cases in which vWD was suspected. RESULTS Four of 50 (8%) consecutive children with a diagnosis of Wilms' tumor were found to have acquired vWD. Laboratory findings indicated type III vWD in two patients and type I vWD in the other two. CONCLUSIONS The incidence of acquired vWD in association with Wilms' tumor merits further study through a large prospective trial. Such a trial should include careful family and clinical bleeding histories plus measurement of a platelet count, BT, coagulant FVIII and vWF levels, RCoF activity, and vWF multimer analysis. The response to 1-desamino-8-D-arginine vasopressin (DDAVP) should be tested in all patients with Wilms' tumor and acquired vWD, including patients with a type III profile, before an invasive procedure is performed. Successful use of DDAVP may avoid exposure of affected patients to blood products.
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Bahou, WF, EJ Bowie, DN Fass, and D. Ginsburg. "Molecular genetic analysis of porcine von Willebrand disease: tight linkage to the von Willebrand factor locus." Blood 72, no. 1 (July 1, 1988): 308–13. http://dx.doi.org/10.1182/blood.v72.1.308.308.
Full textAbstract:
Abstract von Willebrand disease (vWD), one of the most common bleeding disorders in humans, is manifested as a quantitative or qualitative defect in von Willebrand factor (vWF), an adhesive glycoprotein (GP) with critical hemostatic functions. Except for the rare severely affected patient with a gene deletion as etiology of the disease, the molecular basis for vWD is not known. We studied the molecular basis for vWD in a breeding colony of pigs with a disease closely resembling the human disorder. The porcine vWF gene is similar in size and complexity to its human counterpart, and no gross gene deletion or rearrangement was evident as the pathogenesis of porcine vWD. A restriction fragment- length polymorphism (RFLP) within the porcine vWF gene was identified with the restriction endonuclease HindIII, and 22/35 members of the pedigree were analyzed for the polymorphic site. Linkage between the vWF locus and the vWD phenotype was established with a calculated LOD score of 5.3 (1/200,000 probability by chance alone), with no crossovers identified. These findings indicate that porcine vWD is due to a molecular defect within (or near) the vWF locus, most likely representing a point mutation or small insertion/deletion within the vWF gene.
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van Galen, Karin, Merel Timmer, Piet de Kleijn, Kathelijn Fischer, Wouter Foppen, Roger Schutgens, Jeroen Eikenboom, et al. "Joint assessment in von Willebrand disease." Thrombosis and Haemostasis 117, no. 08 (2017): 1465–70. http://dx.doi.org/10.1160/th16-12-0967.
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SummaryAssessment of clinical outcome after joint bleeding is essential to identify joint damage and optimise treatment, to prevent disability. However, disease-specific tools to assess the musculoskeletal status in patients with von Willebrand disease (VWD) are lacking. We aimed to determine validity and reliability of the Haemophilia Joint Health Score (HJHS) and Haemophilia Activities List (HAL) in patients with Von Willebrand disease (VWD). Ninety-six patients with VWD were included (mean age 46 years) of whom 27 had more than five documented joint bleeds. The HJHS was performed in all patients and all patients completed the HAL and Impact on Participation and Autonomy (IPA) questionnaires. Health-related quality of life (SF36) results were obtained from the prior ‘Willebrand in the Netherlands’ study. Joint X-rays of knees, elbows and ankles were scored according to Pettersson (PS). Internal consistency of the HJHS (Cronbach’s α (α)=0.75) and HAL (α=0.89) were good. Inter-observer agreement of the HJHS was good (ICC 0.84; Limits of Agreement ± 10.3). The HJHS showed acceptable correlation with the X-ray PS (Spearman’s r (rs)>0.60 all joints) and HAL (rs=0.71). The HAL also showed acceptable correlation with the SF36 physical functioning (rs=0.65) and IPA (rs=0.69). Hypothesis testing showed adequate discriminative power of both instruments: in patients with a history of >5 versus ≤ 5 joint bleeds (median HJHS 10 vs 2 (p<0.01); median HAL 77 vs 98 (p<0.01)), independent from age. In conclusion, both the HJHS and HAL are feasible to assess clinical outcome after joint bleeds in VWD.
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James, Andra H., Evan R. Myers, Chad Cook, and Ricardo Pietrobon. "Complications of Hysterectomy in Women with Von Willebrand Disease." Blood 112, no. 11 (November 16, 2008): 3399. http://dx.doi.org/10.1182/blood.v112.11.3399.3399.
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Abstract Background: Case reports and small case series suggest that women with von Willebrand disease (VWD) are at a very high risk of bleeding complications with hysterectomy. Because the procedure may be beneficial to women who suffer from heavy menstrual bleeding, an understanding of the true risks involved is essential for appropriate decision making. Objectives: To estimate the incidence of bleeding and other complications in women with VWD who undergo hysterectomy. Methods: The United States Nationwide Inpatient Sample (NIS) from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality for the years 1988–2004 was queried for all hysterectomies for nonmalignant conditions. Data were analyzed based on the NIS sampling design. Bivariate analyses were used to examine the differences between women with and without VWD. Multivariate analysis was used to adjust for potential confounders among women who underwent hysterectomy for heavy menstrual bleeding. Results: 545 of the 1,358,133 hysterectomies were to women with VWD. Women with VWD were significantly more likely to experience intraoperative and postoperative bleeding (2.75% versus 0.89%, p < 0.001) and require transfusion (7.34% versus 2.13%, p < 0.001) than women without VWD. One woman with VWD died (odds ratio = 28.49). Conclusions: While the risk of bleeding complications from hysterectomy in women with VWD is smaller than previously reported, women with VWD did experience significantly more bleeding complications than women without VWD. Nonetheless, for women who have completed childbearing, the risks of hysterectomy may be acceptable.
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Ledford, MR, I. Rabinowitz, JE Sadler, JW Kent, and F. Civantos. "New variant of von Willebrand disease type II with markedly increased levels of von Willebrand factor antigen and dominant mode of inheritance: von Willebrand disease type IIC Miami." Blood 82, no. 1 (July 1, 1993): 169–75. http://dx.doi.org/10.1182/blood.v82.1.169.bloodjournal821169.
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A variant of von Willebrand disease (vWD) was identified in six members of a kindred spanning four generations. The proband was a 46-year-old woman with a lifelong history of bleeding, a prolonged bleeding time (> 15 minutes), markedly elevated von Willebrand factor (vWF) antigen (vWF:Ag = 2.09 U/mL), slightly reduced ristocetin cofactor activity, and a plasma vWF multimer pattern similar to that of vWD type IIC. Similar findings were observed in her three children, mother, and brother. In affected family members, platelet and plasma vWF multimer patterns were discrepant with higher molecular weight multimers observed in platelet vWF. Following a 1-Des-amino-8-D-arginine vasopressin (DDAVP) challenge, the proband failed to normalize her bleeding time even though vWF: Ag rose by 70% and higher molecular weight multimers were increased slightly. Genetic studies were consistent with autosomal dominant inheritance of a mutation within the vWF gene. By sequencing of cloned genomic DNA, mutations were excluded in exons 4, 5, 14, and 15, which encode regions of the vWF propeptide proposed to be important in multimer biosynthesis. Mutations also were excluded in exons 28 to 31, which encompass the known mutations that cause vWD types IIA, IIB, and B. This new variant of vWD, characterized by autosomal dominant inheritance, a qualitative defect that resembles vWD type IIC, and increased plasma vWF:Ag, was tentatively designated vWD type IIC Miami.
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Woods, JP, IB Johnstone, D. Bienzle, G. Balson, and CJ Gartley. "Concurrent lymphangioma, immune-mediated thrombocytopenia, and von Willebrand's disease in a dog." Journal of the American Animal Hospital Association 31, no. 1 (January 1, 1995): 70–76. http://dx.doi.org/10.5326/15473317-31-1-70.
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Lymphangioma, immune-mediated thrombocytopenia (IMT), and von Willebrand's disease (vWD) were diagnosed by histology, hematology, and a coagulation profile in a 14-month-old, female dachshund. Clinical and laboratory findings included ecchymotic inguinolabial swelling, thrombocytopenia, positive platelet factor-3 assay, prolonged buccal mucosal bleeding time, and subnormal von Willebrand factor antigen concentration and factor VIII activity. The IMT resolved with immunosuppressive glucocorticoid therapy. Histologic examination identified lymphangioma which was too extensive for surgical excision. The history and the clinical and laboratory findings were consistent with congenital vWD, although acquired vWD secondary to lymphangioma could not be ruled out.
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Favaloro, Emmanuel. "Collagen Binding Assay for von Willebrand Factor (VWF:CBA): Detection of von Willebrands Disease (VWD), and Discrimination of VWD Subtypes, Depends on Collagen Source." Thrombosis and Haemostasis 83, no. 01 (2000): 127–35. http://dx.doi.org/10.1055/s-0037-1613768.
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SummaryA large number of different collagen preparations [n = 21] have been assessed for their ability to both detect von Willebrands Disease (VWD), and discriminate different VWD subtypes. Collagen preparations were tested at a range of concentrations and included: Type I, III and IV, and various mixtures of these, as aqueous supplied preparations and/or reconstituted from bulk lyophilised stock. Tissue sources for collagens ranged from human placenta to calf skin to equine tendon. Three of the collagen preparations tested did not support von Willebrand factor (VWF) binding in an ELISA process (therefore unable to detect VWD). The ability of the remaining preparations to detect VWF was variable, as was their ability to discriminate VWD subtypes. Detection of VWF and discrimination of VWD subtypes was not mutually inclusive. Thus, some collagen preparations provided excellent detection systems for VWF, but comparatively poorer discrimination of Type 2 VWD, while others provided good to acceptable detection and discrimination. Subtype discrimination was also dependent on the collagen concentration, and some batch to batch variation was evident with some preparations (particularly Type I collagens). Overall, best discrimination was typically achieved with Type I/III collagen mixtures, or Type III collagen preparations (where effectiveness was highly dependent on concentration). Good discrimination was also achieved with a commercial Type III collagen based VWF:CBA kit method. Results of the various ‘VWF:CBA assays’ are also compared with those using the Ristocetin Cofactor (VWF:RCof) assay (by platelet agglutination) and that using a commercial ‘VWF:RCof-alternative/ activity’ ELISA procedure. These latter methodologies tended to be less sensitive to VWF-discordance when compared to that detected by the majority of the VWF:CBA procedures. Abbreviations: FVIII:C Factor VIII: coagulant (assay); HMW High Molecular Weight [VWF]; PNP Pooled Normal Plasma; RIPA Ristocetin induced platelet aggregation procedure; VWD von Willebrands disease; VWF von Willebrand Factor; VWF:Ag von Willebrand Factor Antigen (assay); VWF: CBA Collagen Binding [Activity] Assay for VWF; VWF:RCof Ristocetin Cofactor Assay for VWF
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Noone, Stephanie, Ralf Schubert, Stephan Fichtlscherer, Thomas Hilberg, Sonja Alesci, and Wolfgang Miesbach. "Endothelial Function in Patients With Von Willebrand Disease." Clinical and Applied Thrombosis/Hemostasis 27 (January 1, 2021): 107602962098454. http://dx.doi.org/10.1177/1076029620984546.
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In patients with von Willebrand disease (vWD) the interest in age-related comorbidities has grown, because the life expectancy of these patients has increased. The research question of this study was whether patients with vWD show a different endothelial function compared to the general population. A total of 37 patients with type 1 (n = 23), type 2 (n = 10) and type 3 (n = 4) vWD, 14 controls and 38 patients with coronary artery disease (CAD) were included in this study. Five markers of endothelial dysfunction (MOED) were determined. Moreover, the endothelial function was examined using the Itamar Endo-PAT. The reactive hyperemia index (RHI) was calculated from the results. The markers soluble intercellular adhesion molecule-1 (p = 0.171), P-Selectin (p = 0.512), interleukin-6 (p = 0.734) and monocyte chemoattractant protein-1 (p = 0.761) showed higher levels in patients with vWD, but were not significantly different compared to the control group. RHI was impaired in CAD-patients (1.855), whereas vWD patients had mean results of 1.870 and controls 2.112 (p = 0.367). In this study, the endothelial function measurements of patients with von Willebrand disease were not significantly different compared to healthy controls.
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Lavenu-Bombled, Cécile, Corinne Guitton, Arnaud Dupuis, Marie-Jeanne Baas, Céline Desconclois, Marie Dreyfus, Renhao Li, et al. "A novel platelet-type von Willebrand disease mutation (GP1BA p.Met255Ile) associated with type 2B “Malmö/New York” von Willebrand disease." Thrombosis and Haemostasis 116, no. 12 (November 2016): 1070–78. http://dx.doi.org/10.1160/th16-06-0438.
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SummaryInteraction between von Willebrand factor (VWF) and platelet GPIbα is required for primary haemostasis. Lack or loss-of-function in the ligand-receptor pair results in bleeding complications. Paradoxically, gain-of-function mutations in VWF or GPIbα also result in bleeding complications as observed in type 2B von Willebrand disease (VWD) and platelet-type- (PT-) VWD, respectively. A similar phenotype is observed with increased ristocetin-induced platelet agglutination and disappearance of the highest molecular weight multimers of VWF. We evaluated a patient with a bleeding disorder and a biological presentation compatible with type 2B VWD. VWF and platelet functional assays, sequencing of the VWF and GP1BA genes, and expression studies in HEK cells were performed. Sequencing of the VWF gene in the propositus revealed a heterozygous p.Pro1266Leu mutation previously found in type 2B VWD Malmö/New York. These variants are characterised by a mild phenotype and a normal VWF multimer composition suggesting the presence of a second mutation in our propositus. Sequencing of the GP1BA gene revealed a heterozygous c.765G>A substitution changing Met at position 255 of GPIbα to Ile. This new mutation is located in the β-switch domain where five other gain-of-function mutations have been reported in PT-VWD. Expression of GPIbα Ile255 in HEK GPIb-IX cells resulted in enhanced VWF binding compared to wild-type, similar to known PT-VWD mutations (p.Val249, p.Ser249 and p.Val255) indicating that it contributes to the propositus defects. This first report associating PT-with type 2B VWD illustrates the importance of combining biological assays with genetic testing to better understand the clinical phenotype.
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Wang, J. W., and J. Eikenboom. "Von Willebrand disease and Weibel-Palade bodies." Hämostaseologie 30, no. 03 (2010): 150–55. http://dx.doi.org/10.1055/s-0037-1619048.
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SummaryVon Willebrand factor (VWF) is a pivotal haemostatic protein mediating platelet adhesion to injured endothelium and carrying coagulation factor VIII (FVIII) in the circulation to protect it from premature clearance. Apart from the roles in haemostasis, VWF drives the formation of the endothelial cell specific Weibel-Palade bodies (WPBs), which serve as a regulated storage of VWF and other thrombotic and inflammatory factors. Defects in VWF could lead to the bleeding disorder von Willebrand disease (VWD).Extensive studies have shown that several mutations identified in VWD patients cause an intracellular retention of VWF. However, the effects of such mutations on the formation and function of its storage organelle are largely unknown. This review gives an overview on the role of VWF in WPB biogenesis and summarizes the limited data on the WPBs formed by VWD-causing mutant VWF.
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Schneppenheim, Reinhard, Ulrich Budde, Tobias Obser, Jacqueline Brassard, Kerstin Mainusch, Zaverio M. Ruggeri, Sonja Schneppenheim, Rainer Schwaab, and Johannes Oldenburg. "Expression and characterization of von Willebrand factor dimerization defects in different types of von Willebrand disease." Blood 97, no. 7 (April 1, 2001): 2059–66. http://dx.doi.org/10.1182/blood.v97.7.2059.
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Abstract Dimerization defects of von Willebrand factor (vWF) protomers underlie von Willebrand disease (vWD) type 2A, subtype IID (vWD 2A/IID), and corresponding mutations have been identified at the 3′ end of the vWF gene in exon 52. This study identified and expressed 2 additional mutations in this region, a homozygous defect in a patient with vWD type 3 (C2754W) and a heterozygous frameshift mutation (8566delC) in a patient with vWD type 2A, subtype IIE. Both mutations involve cysteine residues that we propose are possibly essential for dimerization. To prove this hypothesis, transient recombinant expression of each of the 2 mutations introduced in the carboxy-terminal vWF fragment II and in the complete vWF complementary DNA, respectively, were carried out in COS-7 cells and compared with expression of vWD 2A/IID mutation C2773R and the wild-type (WT) sequence in COS-7 cells. Recombinant WT vWF fragment II assembled correctly into a dimer, whereas recombinant mutant fragments were monomeric. Homozygous expression of recombinant mutant full-length vWF resulted in additional dimers, probably through disulfide bonding at the amino-terminal multimerization site, whereas recombinant WT vWF correctly assembled into multimers. Coexpression of recombinant mutant and recombinant WT vWF reproduced the multimer patterns observed in heterozygous individuals. Our results suggest that a common defect of vWF biosynthesis—lack of vWF dimerization—may cause diverse types and subtypes of vWD. We also confirmed previous studies that found that disulfide bonding at the vWF amino-terminal is independent of dimerization at the vWF carboxy-terminal.
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Grundy, Pamela, Stephen Keeney, William Lester, Said Enayat, Andrea Guilliatt, Derrick Bowen, John Pasi, et al. "An investigation of the von Willebrand factor genotype in UK patients diagnosed to have type 1 von Willebrand disease." Thrombosis and Haemostasis 96, no. 11 (2006): 630–41. http://dx.doi.org/10.1160/th06-07-0383.
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SummaryForty families diagnosed by UK centres to have type 1 VWD were recruited. Following review, six families were re-diagnosed to have type 2 VWD, one to have a platelet storage pool disorder, and one family was determined to be unaffected. Direct DNA sequencing of the promoter region and all exons and intronic boundaries of the VWF gene identified six mutations likely to be causative of VWD in index cases of nine of the 32 (28%) confirmed type 1 VWD families. These included R1205H (3614G>A) VWD Vicenza, P1648fsX45 (4944delT), D141G (422A>G) and three splice site mutations: 3108+5G>A, 7437+1G>A and 3379+1G>A. The Y1584C (4751A>G) polymorphism was present in eight additional families. No significant VWF gene mutation or polymorphism was identified in 15 of the32 type 1VWD index cases (47%). Haplotype studies were performed using a panel of VWF polymorphisms to investigate the segregation in families of VWD phenotype with the VWF gene. In 13 of the 32 families it was likely that VWD segregated with the VWF gene. In eight families (25%) VWD clearly did not segregate with the VWF gene. We suggest that mutation screening of the VWF gene has limited general utility in genetic diagnostic and family studies in type 1 VWD. If genetic studies are performed, the incomplete penetrance and variable expressivity of type 1 VWD must be taken into account. Unless linkage of VWD phenotype with the VWF gene can be clearly demonstrated, the results of any genetic family studies should be interpreted with caution.
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Machin, Nicoletta, and Margaret V. Ragni. "Recombinant vs plasma-derived von Willebrand factor to prevent postpartum hemorrhage in von Willebrand disease." Blood Advances 4, no. 14 (July 21, 2020): 3234–38. http://dx.doi.org/10.1182/bloodadvances.2020002046.
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Abstract von Willebrand disease (VWD) is a congenital bleeding disorder characterized by deficient or defective von Willebrand factor (VWF). Among women with VWD, postpartum hemorrhage (PPH) is common. Treatment options at delivery include plasma-derived VWF (pdVWF) and recombinant VWF (rVWF). However, limited data are available regarding their efficacy. We conducted a retrospective observational study comparing PPH in women with VWD treated at the Hemophilia Center of Western Pennsylvania between 1 February 2017 and 31 January 2018 with either rVWF or pdVWF. We compared postpartum outcomes, including PPH frequency and estimated blood loss (EBL) at delivery. There were a total of 12 deliveries, 7 vaginal and 5 cesarean. At delivery and for 3 days postpartum, 6 women received 80 IU/kg of rVWF and 6 received 80 IU/kg of pdVWF, based on prepregnancy weight, insurance, and/or patient choice. Treatment groups had similar demographics, including median age (32.0 vs 27.0 years; P = .075), bleeding scores (3.0 vs 3.5; P = .734), and prepregnancy body mass index (29.0 vs 29.2 kg/m2; P = .691). PPH occurred in 3 (25.0%) of 12 deliveries, with no difference by treatment group (2 of 6 rVWF vs 1 of 6 pdVWF; P = 1.000) and no difference in EBL by treatment group (685 vs 462 mL; P = .384) or delivery type (vaginal, P = .722 vs cesarean, P = .531). In summary, PPH occurred in one-fourth of the deliveries in women with VWD, despite a higher dose (80 IU/kg) of rVWF or pdVWF. Future trials are needed to develop and assess novel strategies to prevent PPH in VWD.
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Guerrero, Jose A., Mark Kyei, Susan Russell, Junling Liu, T. Kent Gartner, Brian Storrie, and Jerry Ware. "Visualizing the von Willebrand factor/glycoprotein Ib-IX axis with a platelet-type von Willebrand disease mutation." Blood 114, no. 27 (December 24, 2009): 5541–46. http://dx.doi.org/10.1182/blood-2009-03-210823.
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AbstractPlatelet-type von Willebrand disease (PT-VWD) is a bleeding disorder of the platelet glycoprotein Ib-IX/von Willebrand factor (VWF) axis caused by mutations in the glycoprotein Ib-IX receptor that lead to an increased affinity with VWF. In this report, platelets from a mouse expressing a mutation associated with PT-VWD have been visualized using state-of-the art image collection and processing. Confocal analysis revealed that VWF bound to the surface of single platelets and bridging micro-aggregates of platelets. Surface-bound VWF appears as a large, linear structure on the surface of 50% of the PT-VWD platelets. In vivo thrombus formation after chemical injury to the carotid artery revealed a severe impairment to occlusion as a consequence of the PT-VWD mutation. In vitro stimulation of PT-VWD platelets with adenosine diphosphate or thrombin demonstrates a significant block in their ability to bind fibrinogen. The impairment of in vivo thrombus formation and in vitro fibrinogen binding are more significant than might be expected from the observed platelet binding to VWF polymers over a small portion of the plasma membrane. Visualization of the receptor/ligand interaction and characterization of a severe antithrombotic phenotype provide a new understanding on the molecular basis of bleeding associated with the PT-VWD phenotype.
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de Jager, Nico C. B., Jessica M. Heijdra, Quincy Kieboom, Marieke J. H. A. Kruip, Frank W. G. Leebeek, Marjon H. Cnossen, and Ron A. A. Mathôt. "Population Pharmacokinetic Modeling of von Willebrand Factor Activity in von Willebrand Disease Patients after Desmopressin Administration." Thrombosis and Haemostasis 120, no. 10 (August 3, 2020): 1407–16. http://dx.doi.org/10.1055/s-0040-1714349.
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Abstract Objective Most von Willebrand disease (VWD) patients can be treated with desmopressin during bleeding or surgery. Large interpatient variability is observed in von Willebrand factor (VWF) activity levels after desmopressin administration. The aim of this study was to develop a pharmacokinetic (PK) model to describe, quantify, and explain this variability. Methods Patients with either VWD or low VWF, receiving an intravenous desmopressin test dose of 0.3 µg kg−1, were included. A PK model was derived on the basis of the individual time profiles of VWF activity. Since no VWF was administered, the VWF dose was arbitrarily set to unity. Interpatient variability in bioavailability (F), volume of distribution (V), and clearance (Cl) was estimated. Results The PK model was developed using 951 VWF activity level measurements from 207 patients diagnosed with a VWD type. Median age was 28 years (range: 5–76), median predose VWF activity was 0.37 IU/mL (range: 0.06–1.13), and median VWF activity response at peak level was 0.64 IU/mL (range: 0.04–4.04). The observed PK profiles were best described using a one-compartment model with allometric scaling. While F increased with age, Cl was dependent on VWD type and sex. Inclusion resulted in a drop in interpatient variability in F and Cl of 81.7 to 60.5% and 92.8 to 76.5%, respectively. Conclusion A PK model was developed, describing VWF activity versus time profile after desmopressin administration in patients with VWD or low VWF. Interpatient variability in response was quantified and partially explained. This model is a starting point toward more accurate prediction of desmopressin dosing effects in VWD.
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Titapiwatanakun, Ruetima, Jennifer C. Guenther, Yan W. Asmann, Todd M. Daniels, John A. Heit, William L. Nichols, and Rajiv K. Pruthi. "Novel Mutations in Types 2 & 3 von Willebrand Disease and Correlation with von Willebrand Factor Multimer Patterns." Blood 110, no. 11 (November 16, 2007): 2136. http://dx.doi.org/10.1182/blood.v110.11.2136.2136.
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Abstract Background & Objectives: Diagnosis and classification of VWD are currently based on integration of personal and family bleeding histories and results of protein-based diagnostic tests (VWF:Ag, VWF:RCo, FVIII:C, VWF:CB and VWF multimers) which have performance limitations. Genetic testing is emerging as a complementary diagnostic tool. We have identified mutations and correlated VWF multimer patterns in our patients (pt) with types 2 & 3 VWD, and report novel candidate mutations. Patients & Methods: Unrelated pt with type 3 (n=6) and subtypes 2 (n=22) VWD, from Mayo Comprehensive Hemophilia Center, consented to this IRB approved study. PCR amplification, from genomic DNA, of VWF gene (splice junctions, coding and promoter regions), avoiding pseudogene amplification, followed by ABI® sequencing and analysis (Mutation Surveyor: SoftGenetic®) were performed. Mutations were compared to VWD (ISTH), NCBI NR nucleotide and DV SNP databases. Comparison with available VWF sequences from other vertebrate species was performed. Selected regions not known to contain mutations remain to be sequenced. VWF multimer analysis was performed using a novel in-gel immunostaining and infrared imaging system. Results: Type 2A VWD (n=10), a novel mutation in exon 28 (E28) (V1524G: 2 pt) with characteristic VWF multimer abnormalities (decreased HMWM, increased satellite banding, suggesting enhanced VWF proteolysis). Type 2B VWD (n=6), 2 pt were compound heterozygous for 2 previously reported mutations, the first in E28 (R1306W)/E48 (T2647M) and the second in E28 (V1316M)/E20 (R854Q). Type 2M VWD (n=4): an 84 yr female with personal (spontaneous and post-surgical) and family bleeding histories, VWF:RCo 72%, VWF:Ag 118% (RCo:Ag ratio 0.61), normal FVIII and platelets, and aberrant VWF multimer banding pattern without substantive reduction of HMWM, had a novel mutation in E52 (S2775C; conserved in mouse, rat, chicken and dog); a 14 yr female with a history of bleeding, VWF:RCo 34%, VWF:Ag 68% (RCo:Ag ratio 0.5) and normal FVIII and platelets, was compound heterozygous for a known mutation (R1399C subtype not classified in VWD database) and two novel mutations: E30 (P1725S) (conserved in mouse, rat, dog, cow and chimp) & E49 (T2666M) (conserved in mouse, dog, rat not in chicken). VWF multimers demonstrated abnormal banding pattern without substantive reduction of HMWM; 2 unrelated pt and families with ultra-large and smeary multimers, previously classified as Vicenza variant, had R1374C mutations and were reclassified as Type 2M VWD. Type 2N VWD (n=1) previously reported mutation E20 (R854Q) was confirmed. Type 3 VWD, 2 pt had novel mutations, the first in E22 (E950X) and the second was a compound heterozygote for E43 (R2478Q)/E40 (E2322V) mutations. In general, patients with similar mutations had similar multimer patterns. Conclusions: We report novel candidate mutations in types 2 & 3 VWD and demonstrate novel VWF multimer patterns with our in-gel staining system. Multimer patterns correlated well with the underlying genotype. The novel mutations are likely causative, given their occurrence at highly conserved residues, but this needs to be confirmed with expression studies. Integration of genetic testing into the diagnostic workup of VWD will potentially lead to more accurate diagnosis and subtyping of VWD, and may further refine protein based testing and provide additional biological insight into VWD.