Von Willebrand Research Articles

Improved prevention of bleeding episodes with emicizumab in 3 patients with concomitant hemophilia A and von Willebrand disease.

The typical phenotype of hemophilia A (HA) is that of frequent bleeding episodes, up to several per month, unless prophylactic factor VIII (FVIII) replacement or alternatives are given. Related bleeding may be heightened in severity or frequency by co-morbid bleeding disorders. Based on the reported prevalence of von Willebrand disease (VWD) of up to 1% of the general population, the co-existence of HA and VWD occurs, but is likely less recognized. Prophylactic FVIII replacement may or may not adequately prevent bleeding in persons with HA and mild VWD, and plasma-derived concentrates containing FVIII and von Willebrand factor (VWF) may be used for more successful bleeding prophylaxis. However, therapy adherence remains problematic for many reasons, one being treatment via intravenous access. Emicizumab is a nonfactor subcutaneous prophylactic therapy for HA that may overcome this concern. We describe three patients, with severe HA and VWD, for whom regular FVIII/VWF prophylaxis was deemed inadequate. FVIII/VWF prophylaxis was replaced with weekly prophylactic injections of the bispecific monoclonal antibody, emicizumab. When the patients were transitioned to emicizumab, all experienced a significant reduction in their annualized bleed rate (ABR). Although the mechanism of action does not directly affect or replace VWF function, emicizumab may be an effective prophylaxis alternative to FVIII/VWF concentrate in patients with concomitant severe HA and VWD.

A Comparative Analysis of the Bleeding Profile and Quality of Life Among Women With Hemophilia Genotype Compared to Other Bleeding Disorders.

Introduction Women with bleeding disorders continue to be underdiagnosed as well as undertreated. Women with bleeding disorders include those with genotype for hemophilia (traditionally named hemophilia carriers), von Willebrand disease (VWD), platelet function disorders, and rare bleeding disorders. Among these women, the carriers of hemophilia are usually considered asymptomatic. The present study compares the bleeding profile and quality of life (QOL) of women and girls with hemophilia and compares it to those diagnosed with VWD and rare bleeding disorders. Methods The present study is part of a prospective observational study (August 2023-July 2028) done on women and girls >12 years in two groups. Group 1 was mothers, sisters, or daughters of patients with hemophilia A who were proven carriers. Group 2 was girls and women registered at our center as following bleeding symptoms and diagnosed as either suffering from VWD or rare bleeding disorders. The bleeding profile was assessed by 1:1 interview using the International Society on Thrombosis and Haemostasis (ISTH) Bleeding Assessment Tool (BAT). Health-related QOL (HRQOL) was assessed using the EuroQOL five dimension (EQ5D5L) questionnaire. Results The baseline data collected in the first six months of this prospective study is being presented here. At the time of submission, the center caters to 970 patients with hemophilia and inherited bleeding disorders. Eighty girls (post pubertal) and women with either obligate carrier status for hemophilia (n=68) or a previously diagnosed bleeding disorder (10 VWD, one afibrinogenemia, one factor VII deficiency) were enrolled.The median age of Group 1 was 35 years (25-70 years), whereas that of Group 2 was 15.5 years (13-23 years). In Group 1 (women and girls with hemophilia (WGH)), 58 and 10 were carriers of hemophilia A and B, respectively. Additionally, 83% of WGH had more than one family member with bleeding disorder, whereas 75% of Group 2 had a positive family history. The number of family members with the same disorder ranged from 0-4. Among 68 hemophilia carrier women, 20 reported bleeding symptoms (29.4%), of which 18 reported menorrhagia, one antepartum hemorrhage, and one post-partum hemorrhage and two had joint/muscle bleeds and one each had ENT and gastrointestinal bleeding. Three of them were admitted for treatment of excessive bleeding and treated with plasma/red cells. Three women reported gynecological procedures for excessive bleeding, one was on treatment for ovarian cysts, and four received packed red cells after delivery. The BAT score above 6 was reported only in 10% of WGH. Eighteen patients had undergone a surgical procedure in their life, and three of these women required a transfusion during surgery. Only one woman reported similar complaints in her daughter. The comparative analysis of HRQOL showed a significantly worse score for Group 1 in EQ5D5L domains for pain and anxiety/depression compared to that of Group 2. Conclusions A significant proportion of previously asymptomatic women with hemophilia carrier status were recognized to have significant bleeding tendencies. The QOL of these carriers is comparable to girls with VWD and rare bleeding disorders and requires special attention.

Von Willebrand Factor Collagen-Binding Activity and Von Willebrand Factor-Mediated Platelet Adhesion in Patients with Coronary Artery Disease.

In this study, we investigated von Willebrand factor (VWF)-related parameters in 30 patients with stable coronary artery disease (CAD) and 50 patients without CAD. In both groups, the following were measured: the VWF antigen level (VWF:Ag); the VWF ristocetin cofactor activity (VWF:RCo); the VWF collagen-binding activity (VWF:CB); and VWF-mediated platelet adhesion. Platelet adhesion was measured in whole blood at a shear rate of 1300 s-1 using a microfluidic chamber with a collagen-coated surface. VWF:Ag and VWF:RCo were found to be the same in both groups of patients. However, VWF:CB was found to be lower in patients with CAD compared with patients without CAD, with values of 106.7% (82.1; 131.6) and 160.4% (112.5; 218.1), respectively (p < 0.001). The decrease in platelet adhesion after GPIb inhibition was more pronounced in patients with CAD compared with patients of the control group, with recorded values of 76.0% (60.6; 82.1) and 29.3% (0.0; 60.4), respectively (p < 0.001). After adjusting for traditional risk factors, the odds ratio for CAD was found to be 0.98 (95% CI, 0.97-0.99; p = 0.011) per 1% increase in VWF:CB activity, and 1.06 (95% CI, 1.03-1.09; p < 0.001) per 1% decrease in GPIb-mediated platelet adhesion. The findings presented in this paper indicate a possible critical role played by complex VWF-collagen-platelet interactions in the development of CAD.

Menorrhagia in inherited bleeding disorders in Iraqi women

Abstract: BACKGROUND: Menorrhagia, or excessive menstrual bleeding, is a common symptom in women with inherited bleeding disorders; they are conditions where the blood ability to clot is impaired. Some of the common bleeding disorders include von Willebrand disease (VWD), clotting factor deficiencies, and platelet function disorders. OBJECTIVE: To assess different types of inherited bleeding disorders in women with menorrhagia referred to the National Center of Hematology/Mustansiriyah University in Baghdad/Iraq. PATIENTS AND METHODS: A prospective study was carried out on 193 women who had experienced menorrhagia for a duration of 3 years, from 2020 to 2023. These women sought consultation at the National Centre of Hematology/Mustansiriyah University. All participants were diagnosed through various laboratory tests, including complete blood count, blood film, blood group and Rh, bleeding time, prothrombin time, activated partial thromboplastin time, fibrinogen level, factor assay, von Willebrand factor antigen using ELISA technique, ristocetin cofactor, and platelet function test. RESULTS: Out of the 193 women with menorrhagia who participated in this study, the majority of whom had an unidentified cause (36.3%), followed by VWD (30.1%) and platelet function disorders (21.2%). Other bleeding disorders (thrombocytopenia and factors deficiencies) were 5.7% and 6.7%, respectively. Furthermore, the results showed that there was a significant difference in family history and consanguinity between patients with a hereditary bleeding disorder and nonhereditary bleeding disorder (P &lt; 0.001). CONCLUSIONS: Fifty eight percent of females with Menorrhagia in this study have inherited bleeding disorders(IBDs), VWD, and thrombasthenia account for 51.3% are the most common causes of inherit bleeding disorder (IBD). Consanguineous marriage should be discouraged in Iraqi society to reduce such inherited diseases.

Single von Willebrand factor C-domain protein-2 confers immune defense against bacterial infections in the silkworm, Bombyx mori

Single-domain von Willebrand factor type C proteins (SVWCs), primarily found in arthropods, responds to infections caused by various pathogens. Three SVWCs have been identified in the silkworm and BmSVWC2 might play a crucial role in the immune system. However, the regulatory mechanism of BmSVWC2 remains largely unknown. This study aimed to investigate the biochemical functions of BmSVWC2 in the immune system of B. mori comprehensively. Phylogenetic analysis revealed that BmSVWC1, BmSVWC3, and BmSVWC2 were distributed in diverse groups, suggesting distinct biochemical functions. The mRNA and protein levels of BmSVWC2 increased significantly in response to bacterial infection. BmSVWC2 exhibited clear binding activity to the polysaccharide pathogen-associated molecular patterns of bacteria and fungi, enhancing bacterial clearance in vivo but not in vitro. RNA-sequencing assays of the fat body and hemocytes showed that numerous immune genes were markedly up-regulated with higher level of BmSVWC2, primarily affecting recognition, signaling, and response production of the Toll and immune deficiency (IMD) signaling pathways. This led to the production of various antimicrobial peptides and significant antibacterial activities in the hemolymph. BmSVWC2 up-regulated phagocytosis-related genes in the fat body and hemocytes, and phagocytosis assays confirmed that BmSVWC2 improved the phagocytic ability of hemocytes against bacteria. Additionally, BmSVWC2 induced the expression of nitric oxide synthetase (NOS) in the fat body, and bioassays confirmed that BmSVWC2 increased NOS activity in the fat body and hemolymph, resulting in nitric oxide accumulation. However, BmSVWC2 did not affect phenoloxidase activity, despite it caused differential expression of a few serine proteases and serine protease inhibitors. Co-immunoprecipitation and mass spectrometry assays showed that BmSVWC2 interacted with 30 K proteins, such as 30 K protein 2, 30 K pBmHPC-19, 30 K 19G1-like, 30 K protein 8, 30 K protein 7, 30 K pBmHPC-23, and low molecular mass lipoprotein 4-like. Our study provides a comprehensive characterization of BmSVWC2 and elucidates the mechanism underlying its regulation of immune responses activation.

Management of von Willebrand Disease for Orthognathic Surgery: Evidenced-Based Recommendations and Scoping Review of the Literature

BackgroundThe general management of von Willebrand Disease has evolved over the past several decades. Advances in blood product replacement manufacturing have led to changes in perioperative management of the bleeding diathesis in its various subtypes. Surgical management follows changes in medical management, but unique perioperative considerations exist depending on the type of surgery. Orthognathic surgery is considered a major surgery that can have life-threatening complications in patients with von Willebrand Disease (vWD) and updates in evidenced-based management are presented. ObjectivesThe objectives of this report are to review available literature regarding management of patients with von Willebrand Disease and other bleeding disorder undergoing orthognathic surgery and to provide a case report regarding the management of a patient vWD type 2M undergoing orthognathic surgery. Eligibility CriteriaArticles included for review were studies addressing patients with bleeding disorders undergoing orthognathic surgery. Sources of EvidencePubMed and Ovid were queried using the terms “orthognathic surgery OR jaw deformity” AND “von Willebrand OR bleeding disorders OR hemophilia.” Additional references relevant to the review were obtained from the reference lists of available articles ultimately deemed appropriate for inclusion in the review. MethodsA recent example case of a patient with type 2M vWD undergoing orthognathic surgery and the patient’s perioperative management is presented for consideration. A scoping review of the literature was undertaken for evaluation of available literature using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Review (PRISMA-ScR). ResultsInsufficient evidence exists for significant analysis of perioperative management strategies previously reported compared to the currently utilized management strategy for the case presented. A review of the available literature with reference to updated literature regarding management of patients with vWD undergoing surgical procedures other than orthognathic surgery yields primarily case reports, two randomized controlled trials, and one systematic review. The results indicate that an evolution in the general management of patients with vWD undergoing surgery can be applied to patients undergoing orthognathic surgery and that the addition of hemostatic agents such as tranexamic acid may be considered with a low level of evidence. ConclusionsFor patients undergoing orthognathic surgery, the use of cryoprecipitate in large quantities has been replaced with the use of Humate-P infusion and will likely be replaced with the use of recombinant von Willebrand factor (VWF). The timing of infusion of adjuncts preoperatively for patients with vWD can potentially be extended to the previous day, and the addition of medications to aid in hemostasis such as tranexamic acid may be considered. Prophylactic use of additional VWF adjuncts should be considered in the postoperative setting, and close monitoring is prudent. The use of newer agents may allow for the expansion of craniomaxillofacial surgery procedures that can be safely considered in patients with vWD.

Lung Fibrosis Is Linked to Increased Endothelial Cell Activation and Dysfunctional Vascular Barrier Integrity.

Pulmonary fibrosis (PF) can be a fatal disease characterized by progressive lung scarring. It is still poorly understood how the pulmonary endothelium is involved in the disease pathogenesis. Differences of the pulmonary vasculature between patients and donors were analyzed using transmission electron microscopy, immunohistochemistry, and single-cell RNA sequencing. Vascular barrier resistance, endothelial-immune cell adhesion, and sensitivity to an inflammatory milieu were studied invitro. Integrity and activation markers were measured by ELISA in human plasma. Transmission electron microscopy demonstrated abnormally swollen endothelial cells (ECs) in fibrotic lungs compared with donors. A more intense CD31 and von Willebrand Factor (vWF) and patchy vascular endothelial (VE)-Cadherin staining in fibrotic lungs supported the presence of a dysregulated endothelium. Integrity markers CD31, VE-Cadherin, Thrombomodulin, and VEGFR-2 (vascular endothelial growth factor receptor-2) and activation marker vWF gene expression was increased in different endothelial subpopulations (e.g., arterial, venous, general capillary, aerocytes) in PF. This was associated with a heightened sensitivity of fibrotic ECs to TNF-α or IFN-γ and elevated immune cell adhesion. The barrier strength was overall reduced in ECs from fibrotic lungs. vWF and IL-8 were increased in the plasma of patients, whereas VE-Cadherin, Thrombomodulin, and VEGFR-2 were decreased. VE-Cadherin staining was also patchy in biopsy tissue and was decreased in plasma samples of patients with PF 6 months after the initial diagnosis. Our data demonstrate highly abnormal ECs in PF. The vascular compartment is characterized by hyperactivation and increased immune cell adhesion, as well as dysfunctional endothelial barrier function. Reestablishing EC homeostasis and function might represent a new therapeutic option for fibrotic lung diseases.

Unfolded von Willebrand factor binds protein S and reduces anticoagulant activity

AbstractThe critical plasma anticoagulant protein S (PS) circulates in 2 functionally distinct pools: free (anticoagulant) or bound to complement component 4b-binding protein (C4BP; anti-inflammatory). Acquired free PS deficiency is detected in several viral infections, but its cause is unclear. Here, we used biochemical approaches and human patient plasma samples to identify an interaction between PS and von Willebrand factor (VWF), which causes free PS deficiency and reduced PS anticoagulant activity. We first identified a shear-dependent interaction between PS and VWF by mass spectrometry. Consistently, PS and VWF could be crosslinked together in plasma, and plasma PS and VWF comigrated in gel electrophoresis. The PS/VWF interaction was blocked by and tissue factor pathway inhibitor but not activated protein C, suggesting an interaction with the sex hormone binding globulin region of PS. Microfluidic systems demonstrated that PS stably binds VWF because VWF unfolds under turbulent flow. PS/VWF complexes also localized to platelet thrombi under laminar arterial flow. In thrombin generation–based assays, shearing plasma decreased PS activity, an effect not seen in the absence of VWF. Finally, free PS deficiency in patients with COVID-19 correlated with changes in VWF, but not C4BP, and with thrombin generation. Our data indicate that PS binds to a shear-exposed site on VWF, thus sequestering free PS and decreasing its anticoagulant activity, which would account for the increased thrombin generation potential. Because many viral infections present with free PS deficiency, elevated circulating VWF, and increased vascular shear, we propose that the PS/VWF interaction reported here is a likely contributor to virus-associated thrombotic risk.

The role of von Willebrand in chronic inflammatory bowel disease

The role of von Willebrand in chronic inflammatory bowel disease

Fibrin clot permeability (Ks) in patients on left ventricular assist device

Patients on left ventricular assist devices (LVAD) are prone to excessive hemostasis disturbances due to permanent contact of artificial pump surfaces with blood components. We aimed to investigate if fibrin clot permeability is altered in patients on long-term continuous-flow LVAD therapy and if the clot permeability is associated with clinical characteristics and adverse events. We investigated 85 end-stage heart failure patients (90.6% men, age 48.6–63.8 years) scheduled for continuous flow long-term LVAD support according to current clinical indications. The patients were assessed periodically: prior to LVAD implantation (T1), 3–6 months (T2) after LVAD implantation, 6–12 months after (T3) and then every 6 months. We tested the first three blood samples (T1-T3) and the last available blood sample (T4), but no longer than 5 years after LVAD implantation. We assessed hemostasis parameters (Activated Partial Thromboplastin Time (APTT) Prothrombin Time, Activated Partial Thromboplastin Time, Fibrinogen, d-dimer, Antithrombin, Thrombin Time, Factor VIII, and von Willebrand Factor, aspirin-induced platelet inhibition, adenosine-diphosphate test) changes during the study period. Fibrin Clot Permeability was evaluated using a pressure system and Permeability Coefficient (Ks) was calculated. We observed a decrease in fibrin clot permeability (Ks) between T1, T2, T3 and T4 time periods; P < 0.01 for each comparison. Fibrin clot permeability was negatively correlated with fibrinogen concentration: r = − 0.51, P < 0.001, factor VIII activity r = − 0.42, P < 0.001. There was no association of Ks with age, Left Ventricular Ejection Fraction (LVEF) and medications P > 0.001, however cumulative measurements in patients on aspirin showed shortening of Ks in this group P = 0.0123. Major adverse cardiac and cerebrovascular events (MACCE) occurred in 36.5% patients, bleeding events in 25.9%, Net Adverse Clinical Events (NACE) in 62.4%; 31.7% patients died, and 17.6% underwent transplantation. The transplantation was considered as the endpoint. Discrepancies in Ks were observed between patients with MACCE, bleeding, and NACE, and patients without adverse events. Ks showed a constant trend towards normalization (P < 0.01) only in patients without adverse events. Patients with advanced heart failure have disturbed clot structure. A trend towards normalization of the Ks values is associated with fewer thromboembolic and bleeding complications in this group of patients.

Association of periodontitis with cardiometabolic and haemostatic parameters

ObjectiveTo investigate the association between periodontitis and cardiometabolic and haemostatic parameters.Materials and methodsBetween 2014 and 2019, 54 individuals needing full mouth extraction, and 50 control individuals, were recruited for a combined cross-sectional (individuals versus controls) and longitudinal (individuals before and after extraction) study. Periodontitis severity was measured using the periodontal inflamed surface area (PISA). Blood was drawn to measure the haemostatic (Factor VIII, von Willebrand factor [VWF], endogenous thrombin potential, d-dimer, clot lysis time) and cardiovascular risk (C-reactive protein [CRP], lipid profile) parameters, prior to and 12 weeks post-extraction. The results were analysed group-wise.ResultsThe mean VWF and CRP levels were higher and the high-density lipoprotein levels were lower in the individuals prior to extraction compared to the controls. The VWF was significantly correlated with the PISA (a 21% unit increase in VWF per 1000 mm2 increase in PISA, 95%CI: 6–36%, p = 0.01). The other analyses were comparable between the individuals and controls, and did not change in the individuals after the extraction.ConclusionVWF levels are associated with periodontitis severity; they do not improve after full-mouth extraction. Severe periodontitis in control individuals does not induce substantial changes in their haemostatic or inflammatory systems.Clinical relevanceTreatment of periodontitis has been shown to improve the cardiometabolic blood profile of patients with established cardiometabolic disease. However, whether periodontitis treatment improves cardiometabolic and haemostatic profiles in people without cardiometabolic disease is uncertain.

Legionella Pneumophila Presenting as a Rare Cause of Acute Thrombocytopenia: A Case Report and Review of Literature.

Legionella pneumophila can cause a wide spectrum of clinical manifestations, ranging from a mild flu-like illness to fulminant multi-organ involvement, characterised by severe pneumonia, diarrhoea, encephalopathy, shock, hepatic dysfunction and renal failure. Very rarely, it can be associated with haematologic conditions such as thrombotic thrombocytopenic purpura (TTP), haemolytic uraemic syndrome (HUS) and immune thrombocytopenic purpura (ITP). We report a rare case of L. pneumophila causing ITP and review previously published cases of thrombocytopenia associated with Legionellosis in the literature. A 53-year-old male presented with fevers, chills, a productive cough and severe haemoptysis. Blood work was remarkable for leukocytosis, severe thrombocytopenia and hyponatraemia. Computed tomography (CT) imaging showed left lower lobe lung consolidation, and a peripheral blood smear showed giant platelets consistent with ITP. Legionella urine antigen testing returned positive. He was treated with intravenous immunoglobin, steroid taper and a ten-day course of azithromycin, which led to normalisation of his platelet count and resolution of the pneumonia. L. pneumophila can lead to complement-mediated destruction of platelets resulting in ITP. Antibodies against L. pneumophila can also cross-react with the enzyme ADAMTS13, inhibiting its function and resulting in TTP and HUS. Additionally, L. pneumophila can infect vascular endothelial cells causing their death and stimulating release of von Willebrand factor (vWF) multimers into the bloodstream, promoting thrombosis and platelet consumption. It is important for internists to consider L. pneumophila in the differential for any patient presenting with pneumonia and severe thrombocytopenia. Earlier detection and intervention can lead to prevention of critical bleeding and better outcomes. Legionella pneumophila is rarely associated with different haematologic disorders resulting in severe bleeding diathesis as well as thrombosis.It is important for internists to consider Legionella pneumophila in the differential diagnosis for any patient presenting with pneumonia and severe thrombocytopenia.Earlier detection and intervention can lead to prevention of critical bleeding and better outcomes.

Von Willebrand factor in inflammation and heart failure: beyond thromboembolic and bleeding risk.

Von Willebrand factor in inflammation and heart failure: beyond thromboembolic and bleeding risk.

Evaluation of FVIII pharmacokinetic profiles in Korean hemophilia A patients assessed with myPKFiT: a retrospective chart review

PurposeThis study aimed to investigate the pharmacokinetics (PK) of factor VIII (FVIII) in Korean patients, as limited information is available on the PK of FVIII in this population.MethodsWe collected the FVIII PK results from patients with moderate-to-severe hemophilia A using myPKFiT. PK variations were assessed according to age, blood type, inhibitor history, von Willebrand factor antigen (vWF:Ag) level, and body mass index. Additionally, the correlation between the PK profile and prophylaxis regimen was specifically analyzed for each product in severe cases.ResultsThe PK data of 48 and 81 patients treated with octocog alfa and rurioctocog alfa pegol, respectively, were obtained. The median half-lives of octocog alfa and rurioctocog alfa pegol were 9.9 (range: 6.3–15.2) h and 15.3 (range: 10.4–23.9) h, respectively. The PK profiles for each product did not differ according to age group; however, blood type-O patients had shorter half-lives and time to 1% compared to non-blood type-O patients. In regression analysis, the PK of octocog alfa showed a statistically significant difference according to age, whereas the PK of rurioctocog alfa pegol correlated with vWF:Ag. Only the frequency of rurioctocog alfa pegol use showed a statistically significant difference in relation to time to 1%, although the coefficient of determination was small.ConclusionThis study confirmed significant interpatient variation in the PK of FVIII among Korean patients with hemophilia A. To achieve optimized prophylaxis, personalizing the regimen based on the PK profile of each individual patient is essential.

The clinical impact of acquired von Willebrand syndrome secondary to Waldenström macroglobulinemia: an underrecognized source of major bleeding events.

The clinical impact of acquired von Willebrand syndrome secondary to Waldenström macroglobulinemia: an underrecognized source of major bleeding events.

Platelet-Type von Willebrand Disease: Complex Pathophysiology and Insights on Novel Therapeutic and Diagnostic Strategies.

von Willebrand disease (VWD) is the most common well-studied genetic bleeding disorder worldwide. Much less is known about platelet-type VWD (PT-VWD), a rare platelet function defect, and a "nonidentical" twin bleeding phenotype to type 2B VWD (2B-VWD). Rather than a defect in the von Willebrand factor (VWF) gene, PT-VWD is caused by a platelet GP1BA mutation leading to a hyperaffinity of the glycoprotein Ibα (GPIbα) platelet surface receptor for VWF, and thus increased platelet clearing and high-molecular-weight VWF multimer elimination. Nine GP1BA gene mutations are known. It is historically believed that this enhanced binding was enabled by the β-switch region of GPIbα adopting an extended β-hairpin form. Recent evidence suggests the pathological conformation that destabilizes the compact triangular form of the R-loop-the GPIbα protein's region for VWF binding. PT-VWD is often misdiagnosed as 2B-VWD, even the though distinction between the two is crucial for proper treatment, as the former requires platelet transfusions, while the latter requires VWF/FVIII concentrate administration. Nevertheless, these PT-VWD treatments remain unsatisfactory, owing to their high cost, low availability, risk of alloimmunity, and the need to carefully balance platelet administration. Antibodies such as 6B4 remain undependable as an alternative therapy due to their questionable efficacy and high costs for this purpose. On the other hand, synthetic peptide therapeutics developed with In-Silico Protein Synthesizer to disrupt the association between GPIbα and VWF show preliminary promise as a therapy based on in vitro experiments. Such peptides could serve as an effective diagnostic technology for discriminating between 2B-VWD and PT-VWD, or potentially all forms of VWD, based on their high specificity. This field is rapidly growing and the current review sheds light on the complex pathology and some novel potential therapeutic and diagnostic strategies.

Clinical and molecular features of first two-sibling-Cambodian girls with musculocontractural Ehlers-Danlos syndrome

Musculocontractural Ehlers-Danlos syndrome (mcEDS) is a rare autosomal recessive connective tissue disorder. To our knowledge, mcEDS has not previously been reported in Cambodia. Here, we report clinical presentations and a novel variant of CHST14 causing mcEDS in the two siblings in Cambodia. These patients from a non-consanguineous parents presented with clubfeet at birth, contractures of thumbs and feet, a typical facial appearance, and normal cognitive development. The elder sister had severe phenotypic features than the younger sister. They have been prone to ecchymosis and hematomas with minor accidents since young age, without accurate diagnosis, or confused with von-willebrand disease. Genetic consultation and confirmed by a genetic analysis revealed a novel variant, c.994-997dup, (Pro333Glnfs×23) of CHST14. Treated with oral desmopressin and daily vitamin C supplementation over 1-year-period of follow-up, the bleeding has been improved. The purpose of this article is to describe the clinical and molecular features and to show the missed or inaccurate diagnosis of this rare syndrome, which, consequently, results in suboptimal symptomatic management.

No effect of surgery on kidney and cardiovascular risk factors in mild primary hyperparathyroidism: secondary analyses from a 10-year randomized controlled trial.

Renal function and the skeleton are classic target organs in primary hyperparathyroidism (PHPT), affected by the chronic course of the disease. Most patients diagnosed today exhibit mild PHPT, characterized by slight hypercalcemia and no or unspecific symptoms. Concerns have been raised that PHPT could promote deteriorating kidney function and increase cardiovascular risk directly. To examine the effect of parathyroidectomy (PTX) on mild PHPT on renal function and markers for bone turnover, cardiovascular disease (CVD), and vascular inflammation. Prospective randomized controlled trial. ClinicalTrials.gov: NCT00522028. Eight Scandinavian referral centers. From 1998 to 2005, 191 patients with mild PHPT were included in Sweden, Norway, and Denmark. Of these 150 were included in the present analyses. Seventy patients were randomized to PTX and 80 to observation without intervention (OBS). e-GFR was calculated based on creatinine and cystatin C. Markers of CVD and systemic inflammation: osteoprotegerin, vascular cell adhesion molecule 1, soluble CD40 ligand, interleukin-1 receptor antagonist, von Willebrand factor. Bone turnover markers: C-terminal telopeptide of type 1 collagen (CTX-1) and serum Procollagen type 1 N-terminal propeptide. No differences in the development of renal function or vascular and systemic inflammation were detected. CTX-1 was lower in PTX after 10 years. Secondary analyses of a randomized controlled trial. PTX does not appear to affect renal function or markers of CVD and vascular inflammation in mild PHPT in a ten-year perspective.

When Type 1 von Willebrand Disease Lives Together with Hashimoto Thyroiditis, Hypothyroidism, Hypoparathyroidism, Morbid Obesity, and Bariatric Surgery: A Case Report

Von Willebrand disease (vWD) is the most common bleeding disorder with type 1 being the more prevalent, although underdiagnosis is an actual concern. This case is the first clinical report of a type 1 vWD with several comorbidities submitted to bariatric surgery. The authors demonstrate the importance of a diagnosis and the consideration of other diseases or disturbances in vWD patients’ perioperative management. A multidisciplinary approach is crucial for minimizing and preventing bleeding risk.

Lymphatic and blood vessels in parathyroid tumors: Immunohistochemical study with LYVE-1 and von Willebrand factor.

Parathyroid tumors exhibit distinct histopathological features that differentiate benign from malignant lesions. This study aimed to study characteristic distribution of lymphatic and blood vessels in normal parathyroid gland and parathyroid tumors to distinguish cancer from benign tumors. Immunohistochemical staining for lymphatic and blood vessels and parathyroid hormone was performed with parathyroid proliferating lesions including adenoma, multiglandular multiple adenomas, atypical tumor, and carcinoma. Lymphatic vessels were immunostained with lymphatic vessel endothelial receptor 1 (LYVE-1) and blood vessels were immunostained with von Willebrand factor (vWf). Normal parathyroid gland contained several round blood vessels with less linear lymphatic vessels. The less parathormone-immunostained adenomas weighing less than 2 g revealed larger blood vessels with perivascular small linear lymphatic vessels, and the larger adenomas contained proportionally larger blood vessels. Smaller multiglandular multiple adenomas were like smaller adenomas with less parathormone staining and contained larger, round blood vessels with perivascular small linear lymphatic vessels. Larger multiglandular multiple adenomas weighing more than 4 g and one atypical tumor contained nodular pattern consisted of alternating strongly parathormone-positive lobes and negative lobes with numerous, dilated blood vessels and perivascular linear lymphatic vessels. Both primary and metastatic carcinomas were strongly and diffusely positive for parathyroid hormone with numerous lymphatic and blood vessels at the invading margin. Thus, normal parathyroid has rich blood vessels which provide accessibility of minced tissues seeding for auto-transplantation. Immunostaining patterns of parathyroid hormone, lymphatic and blood vessels help to distinguish carcinoma from benign parathyroid proliferating lesions. The negative immunohistochemical staining for parafibromin will detect carriers of hyperparathyroidism-jaw tumor (HPT-JT) syndrome and would help in diagnosing parathyroid cancer in both HPT-JT carriers and sporadic patients.