Von Willebrand disease (VWD) is an inherited bleeding disorder caused by quantitative and qualitative abnormalities of von Willebrand factor (VWF), a multimeric glycoprotein that is the largest of its kind in plasma and is also found in platelet alpha granules and Weibel-Palade bodies of endothelial cells. VWF plays two roles in hemostasis: (1) primary hemostasis via adhesion of platelet GPIb to subendothelial connective tissue and (2) stabilization of coagulation factor VIII. The pathological classification proposed by the International Society of Thrombosis and Haemostasis (ISTH) in 1994 divided VWF into three major categories based on the results of VWF:RCo, VWF:Ag, and multimer analysis. Recent genetic analysis and molecular and cellular analysis of abnormal VWF have revealed a molecular basis for the dominant inheritance form of VWD.

We present a case of a woman in her 20s with inadequately treated systemic lupus erythematosus (SLE). She presented with heavy menstrual bleeding, along with nasal and gum bleeding worsening over 3 months. There was no bleeding history in her family, childhood, dental procedures or childbirth. Evaluation ruled out structural causes, revealing prolonged activated partial thromboplastin time (incomplete correction on mixing studies), normal prothrombin time, moderate thrombocytopenia, and lupus anticoagulant and anti-phosphatidylserine/prothrombin antibody positivity twice, 12 weeks apart. Further evaluation showed very low von Willebrand factor (vWF) levels (<5%). She was treated with pulse methylprednisolone for 3 days, resulting in complete symptom resolution and improvement in vWF levels to 130%. The absence of bleeding history, family history, presence of very low vWF and its response to corticosteroids led to a diagnosis of acquired vWF syndrome as the cause of mucosal bleeding in an SLE patient with concomitant positive antiphospholipid antibody. She was discharged on hydroxychloroquine, mycophenolate mofetil and tapering oral corticosteroids.

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UNASSIGNED: Between 2002 and 2011, the incidence of severe primary postpartum hemorrhage (PPH) in Dutch women with von Willebrand disease (VWD) and hemophilia carriers (HCs) was 8% vs 4.5% in the general population.
UNASSIGNED: To determine the contemporary incidence of severe primary PPH in women with VWD and HCs.
UNASSIGNED: All women with VWD or HCs who delivered between 2012 and 2017 were selected from all 6 Dutch hemophilia treatment centers. Data on patient and disease characteristics, peripartum hematologic and obstetric management, and outcomes were retrospectively collected. Incidence of severe primary (≥1000 mL of blood loss ≤24 hours after childbirth) and primary (≥500 mL within ≤24 hours after childbirth) PPH was compared with the (1) previous cohort and (2) general Dutch population and between (3) women with VWD and HCs with third-trimester coagulation activity levels <50 international units (IU)/dL vs ≥50 IU/dL and (4) women treated with vs without peripartum hemostatic prophylaxis.
UNASSIGNED: Three-hundred forty-eight deliveries (151 VWD, 167 hemophilia A, and 30 hemophilia B carriers) were included. The severe primary PPH incidence was 10% (36/348) and remained stable over time, whereas this incidence has increased in the general population (to 8%), leading to a similar risk (P = .17). Severe primary PPH risk was comparable between women with coagulation activity levels <50 and ≥50 IU/dL (11% [7/66] vs 10% [29/279]; odds ratio, 1.02; 95% CI, 0.43-2.44) and comparable between those with and those without prophylaxis (12% [11/91] vs 10% [25/254]; odds ratio, 1.26; 95% CI, 0.59-2.68).
UNASSIGNED: Severe primary PPH in women with VWD and HCs remained stable and is comparable with the increasing prevalence in the general population. More research is needed to find the optimal pregnancy management strategy for safe delivery in VWD and HC.

UNASSIGNED: Von Willebrand disease (VWD) is the most common inherited bleeding disorder, affecting about 0.6% to 1.3% of the population, and is characterized primarily by mucocutaneous bleeding secondary to defective platelet adhesion and aggregation. Current therapeutic options for those with severe disease are limited and require frequent intravenous infusions.
UNASSIGNED: This review discusses the current and recently completed clinical trials involving pathways to FVIII augmentation for the treatment of VWD. Clinical trials registered on clinicaltrials.gov and published data via PubMed searches through June 2024 were included.
UNASSIGNED: Available treatment options to those with VWD are limited in part due to limited clinical trials, the complexity of VWD types, and the pharmacokinetics of current treatment options. The development of therapeutic options that reduce treatment burden is necessary to improve quality of life and reduce bleeding complications and in recent years there has been an increased interest from industry to apply novel therapeutics for VWD. The FVIII mimetic, emicizumab, has demonstrated early success in patients with severe VWD and is a promising treatment option for those who require prophylaxis. Furthermore, products like efanesoctocog alfa (Altuviiio®) and BT200 have achieved enhanced VWF/FVIII half-life extension could expand the current treatment landscape while concurrently minimizing treatment burden.

A 28-year-old woman was found to have coagulation factor Ⅷ activity (FⅧ∶C) <1% and von Willebrand factor antigen (VWF∶Ag) <1% during routine prenatal examinations. No pathogenic variation was found in the exon region of the VWF gene using next-generation sequencing. The clinical presentation of this patient does not match the clinical characteristics of type Ⅲ hemophilia [von Willebrand disease (VWD) ]; therefore, third-generation sequencing technology was used to perform whole-genome sequencing on the patient and her family members. Multiple members of the patient\'s paternal family carried a heterozygous variant of VPS33B, c.869G>C. The family members carrying this variant all had varying degrees of reduced VWF levels (39% -56% ). Moreover, the proband was detected with the heterozygous variant c.1474dupA in GP1BA. The ACMG and Clinvar databases determined that this variation was associated with platelet-type pseudo VWD. The decrease in VWF levels caused by heterozygous variations in VPS33B in families is the first international report, and no previous studies have reported cases of severe decrease in plasma VWF levels caused by double heterozygous variations in VPS33B and GP1BA.
一例28岁女性，孕期常规体检发现凝血因子Ⅷ活性（FⅧ∶C）<1%、血管性血友病因子抗原（VWF∶Ag）<1%。二代测序未发现其VWF基因外显子区域存在致病变异。由于该患者临床表现与Ⅲ型血管性血友病（VWD）临床特征不符，因此采用三代测序技术对该患者及其家系成员进行全基因组测序，发现该患者父系家族中有多位成员中携带VPS33B基因杂合变异c.869G>C，携带该变异的家系成员均有不同程度的VWF水平降低（39%～56%）。同时，先证者还检出GP1BA基因杂合变异c.1474dupA，ACMG及Clinvar数据库判断该变异与\"血小板型假性VWD\"相关。VPS33B基因杂合变异导致的VWF水平降低家系为国际首次报道，VPS33B基因与GP1BA基因双重杂合变异引起血浆VWF水平严重降低病例之前也未见报道。.

UNASSIGNED: Patient-reported outcomes measurement information system (PROMIS) measures can be used to measure patient-reported outcomes. PROMIS measures, including computer adaptive tests (CATs) and short forms, have demonstrated the ability to adequately assess outcomes in patients with hemophilia. It is, however, unclear if PROMIS measures are suitable for patients with von Willebrand disease (VWD), inherited platelet function disorders (IPFDs), and rare bleeding disorders (RBDs).
UNASSIGNED: To evaluate the feasibility, measurement properties, and relevance of PROMIS measures in adults with VWD, IPFDs, and RBDs.
UNASSIGNED: In this cross-sectional multicenter study, adults with VWD, IPFDs, and RBDs completed 9 PROMIS measures and the Short Form-36 version 2 (SF-36v2) electronically. Feasibility was determined by the number of completed items and floor/ceiling effects. Measurement properties included construct validity based on a multitrait-multimethod analysis and reliability using the reliability coefficient and greatest lower bound. Relevance was evaluated based on comparison with the Dutch general population.
UNASSIGNED: In total, 111 patients (median age, 57 years [IQR, 44-67]; 60% VWD, 16% IPFD, 24% RBD) participated. Mean number of items answered varied from 5.3 to 8.7 (range, 4-12) per PROMIS CAT in patients with VWD. Construct validity was supported for all CATs and all instruments had a good reliability (≥0.70). The PROMIS measures had less ceiling effects than the SF-36v2.
UNASSIGNED: The PROMIS measures are a feasible, valid, and reliable alternative for the SF-36v2 in patients with primarily nonsevere forms of VWD. The relevance of the selected measures was limited. Additional research is necessary to evaluate the PROMIS measures in adults with IPFDs and RBDs.

von Willebrand disease (VWD) is the most common inherited bleeding disorder. The disorder is characterized by excessive mucocutaneous bleeding. The most common bleeding manifestations of this condition include nosebleeds, bruising, bleeding from minor wounds, menorrhagia or postpartum bleeding in women as well as bleeding after surgery. Other less frequent symptoms include gastrointestinal bleeding, haematomas or haemarthroses. VWD pathophysiology is complex and results from defects in von Willebrand factor (VWF) glycoprotein. Quantitative deficiencies are responsible for type 1 VWD with a partial decrease of VWF and type 3 with the complete absence of VWF. Qualitative abnormalities cause type 2 VWD, being further divided into types 2A, 2B, 2M and 2N. Although common, VWD is at risk of misdiagnosis, overdiagnosis and underdiagnosis owing to several factors, including complex diagnosis, variability of bleeding symptoms, presence of external variables (blood groups and other physiological modifiers such as exercise, thyroid hormones, oestrogens, and ageing), and lack of disease awareness among non-specialist health-care providers. Establishing the correct VWD diagnosis requires an array of specialized phenotypic assays and/or molecular genetic testing of the VWF gene. The management of bleeding includes increasing endogenous VWF levels with desmopressin or infusion of exogenous VWF concentrates (plasma-derived or recombinant). Fibrinolytic inhibitors, topical haemostatic agents and hormonal therapies are used as effective adjunctive measures.

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BACKGROUND: Historically, von Willebrand factor (VWF) activity assays utilized ristocetin despite limitations including poor limits of detection and high imprecision. Newer VWF activity assays such as the INNOVANCE® VWF Ac assay, however, do not rely on ristocetin to measure platelet-dependent VWF function. The purpose of this study was to evaluate the analytical and clinical performance of the Siemens Healthineers INNOVANCE VWF Ac Assay on the Siemens BCS® XP and the Sysmex® CS-2500 systems in a large reference laboratory setting.
METHODS: Performance indicators for the INNOVANCE VWF Ac assay were the limit of quantitation (LoQ), precision, and method comparison. Method comparison studies were performed using remnant plasma patient samples from routine coagulation tests and analyzed using both the INNOVANCE VWF Ac assay and the Siemens Healthineers ristocetin-dependent BC von Willebrand Reagent.
RESULTS: Evaluation of the INNOVANCE VWF Ac assay on the BCS® XP and CS-2500 systems demonstrated good precision and a lower LoQ compared to the BC von Willebrand Reagent. Method comparisons support the use of the INNOVANCE VWF Ac assay on the BCS® XP and CS-2500 systems to measure platelet-dependent VWF function. The INNOVANCE VWF Ac assay was able to further assist in von Willebrand disease classification in 6/7 (86%) samples when the result was below the LoQ for the BC von Willebrand Reagent (ristocetin cofactor activity).
CONCLUSIONS: These data are consistent with the 2021 American Society of Hematology/International Society on Thrombosis and Haemostasis/National Hemophilia Foundation/World Federation of Hemophilia von Willebrand disease guidelines that suggest using newer assays such as the INNOVANCE VWF Ac assay in place of ristocetin cofactor activity assays.