A new ELISA assay for diagnosis of acquired von Willebrand syndrome

Surprise diagnosis of acquired von Willebrand syndrome in a patient previously thought to have type III von Willebrand disease: evaluation and periprocedural management

Acquired von Willebrand syndrome (AVWS) is a rare disorder that is characterised by an acquired deficiency of von Willebrand factor. AVWS was suspected in a patient with type III von Willebrand disease (VWD) who did not respond to factor replacement therapy. Given the crucial implications for management, we describe this patient's clinical presentation, diagnosis and periprocedural management. To facilitate pericardiocentesis, periprocedural management included steroids, intravenous immunoglobulin and factor replacement therapy. In other patients with suspected immune-mediated AVWS, a similar approach may be effective. This case also highlights the importance of distinguishing AVWS from inherited VWD.

Acquired von Willebrand syndrome: Five cases report and literature review

Acquired von Willebrand syndrome is a rare bleeding disorder with laboratory findings similar to those of inherited von Willebrand disease. Principal factors distinguishing acquired von Willebrand syndrome from the latter condition include lack of prior bleeding disorders, diagnosis at older age, negative family history and association with underlying conditions.

METHODS

Retrospective, monocentric descriptive case series of acquired von Willebrand syndrome diagnosed between 2010 and 2020. Diagnostic criteria included a recent history of bleeding, a negative family history and a presence of underlying disorders.

RESULTS

Five men were diagnosed with acquired von Willebrand syndrome. All of them presented with recent mucocutaneous bleeding. The biological phenotype was a type 2 von Willebrand disease in all cases, with decreased VWF:RCo/VWF:Ag and VWF:CB/VWF:Ag ratios (<0.7). Lymphoproliferative, autoimmune and cardiovascular diseases were the main underlying conditions identified. Screening for an anti-von Willebrand factor inhibitor was positive in two patients. Four patients received treatment for the underlying disorder. High-dose intravenous immunoglobulins were the most frequent treatment administrated. Improvement of plasma von Willebrand factor levels was observed in four cases.

CONCLUSION

Acquired von Willebrand syndrome is a rare but potentially serious disease. The diagnostic should be suspected in adults with unusual mucocutaneous bleeding associated with lymphoproliferative, myeloproliferative, autoimmune and cardiovascular disorders.

A Review of Autoimmune Acquired von Willebrand Factor Deficiency in Japan

von Willebrand factor (VWF) forms high-molecular-weight multimers and plays an essential role in hemostasis, and thus its deficiency leads to bleeding symptoms. Acquired von Willebrand syndrome (AVWS) is rare, but potentially underdiagnosed, and develops in various underlying disorders. AVWS caused by anti-VWF autoantibodies is a rare subcategory of AVWS that can also be referred to as autoimmune VWF deficiency (AiVWFD). We performed a search of patients with autoimmune coagulation factor deficiencies in our nationwide survey in Japan. Among these, suspected cases of AiVWFD were extremely few, with only 11 case consultations in the last 10 years. Of these, three and five were respectively positive for anti-VWF autoantibodies (anti-VWF-Ab) and VWF inhibitor (VWF-inh). We also performed an extensive literature search of other cases from Japan, and in total, 40 cases were finally identified to have AiVWFD, with mean age of 55.0 years. Most underlying disorders were lympho- or myeloproliferative diseases, followed by autoimmune diseases. The major bleeding sites were subcutaneous and mucosal, the bleeding severity was moderate, and there were no hemorrhagic deaths. Bleeding time was prolonged; factor VIII activity, VWF antigen, and VWF activity were decreased, and high-molecular-weight VWF multimers were absent or decreased. These are similar to the common abnormal laboratory findings observed among general AVWS cases. Hemostatic therapy often involved VWF concentrates and vasopressin, and antibody eradication therapy often included corticosteroids and achieved remission. Notably, of all cases, 68% had anti-VWF-Abs, and 83% of anti-VWF-Ab-positive patients were also VWF-inh positive. To accumulate precise clinical information on AiVWFD, it is necessary to verify and improve the measurement methods for both anti-VWF-Ab and anti-VWF-inh. These findings from Japan should be confirmed in other geographic localities.

Rare Occurrence of Inhibitors in Von Willebrand Disease: A Case Report

Introduction: Type 3 Von Willebrand Disease (VWD) is the least common but the most severe form of a disease, with a prevalence of about 0. 5 to 1 per million in Western countries. The prevalence of type 3 VWD in the developing countries, with a high degree of consanguinity, is about 6 per million. Moreover, due to underdiagnosis of the milder cases, the prevalence of type 3 VWD is about 50% of the cases. Rarely, some patients develop the Von Willebrand Factor (VWF) inhibitors, which may subsequently develop severe anaphylactic reactions on further exposure to the VWF containing factor replacement therapy. The prevalence of inhibitor development in patients with type 3 VWD has been shown to be in the range of 5.8 to 9.5%. In the absence of a gold standard assay for the quantitation of VWF inhibitors, a correct diagnosis and management of these patients are often challenging.

Objectives: The objective of this study is to standardize the Bethesda assay for the VWF inhibitors and to estimate the VWD inhibitor titer in two cases of congenital type 3 VWD, which developed the VWF inhibitors.

Results and Conclusions: We could successfully standardize the Bethesda assay for the quantitation of VWF inhibitors in two patients with congenital type 3 VWD with inhibitors.

Acquired von Willebrand syndrome: focused for hematologists

The acquired von Willebrand syndrome (AvWS) is a rare bleeding disorder with laboratory findings similar to those of inherited von Willebrand disease. However, unlike the inherited disease, AvWS occurs in persons with no personal and family history of bleeding and is often associated with a variety of underlying diseases, most frequently lymphoproliferative, myeloproliferative and cardiovascular disorders. After the presentation of a typical case, in this narrative review we discuss the more recent data on the pathophysiology, clinical, laboratory and therapeutic aspects of this acquired bleeding syndrome. We chose to focus particularly on those aspects of greater interest for the hematologist.

von Willebrand factor alloantibodies in type 3 von Willebrand disease

: The development of neutralizing antibodies is a rare complication of von Willebrand disease treatment. In major surgical procedures for severe forms of the disease, the recognition of ineffective therapy and alternative treatment protocols are lifesaving. We report the case of a 6-year-old girl with type 3 von Willebrand disease in whom inhibitors were sought due to ineffective haemostasis together with lower than expected von Willebrand factor (VWF) recoveries after a surgical procedure. Replacement therapy first with recombinant factor VIIa and then with high doses of recombinant factor VIII in continuous infusion successfully stopped the bleeding. A high level of anti-VWF antibodies was determined by the immunological method. A frameshift mutation associated with premature termination codon (c.2435delC, p.Pro812ArgfsTer31) was determined in our patient. Although the reports on association of this mutation with inhibitor risk are inconsistent, it represents an evidence-based diagnostic and management practice in recognition of high-risk VWF genotype.

Combination of acquired von Willebrand syndrome (AVWS) and Glanzmann thrombasthenia in monoclonal gammopathy of uncertain significance (MGUS), a case report

Background

Autoimmune paraphenomena, are associated with B-cell lymphoproliferative disorders, including monoclonal gammopathy of uncertain significance. These paraphenomena can rarely include acquired bleeding disorders.

Case presentation

This case study reports an unusual clinical presentation of 2 acquired bleeding disorders, Acquired von Willebrand syndrome (disease) and Acquired Glanzmann's thrombasthenia, in an elderly patient with monoclonal gammopathy of uncertain significance.

Conclusions

Acquired bleeding disorders are often underdiagnosed and a high degree of clinical suspicion is required. The patient in this study demonstrated platelet aggregometry which was atypical for isolated Glanzmann's thrombosthenia because of the severe concomitant endogenous decrease in von Willebrand factor. There was an absence of platelet aggregation to all tested agonists including ristocetin. Once the diagnosis was made, however, the patient showed a partial response to intravenous immunoglobulin confirming the immunological pathogenesis in this case. This case highlights the need to consider acquired bleeding disorders in patients with a possible predisposing factor.

Genotype-phenotype correlation in a cohort of Portuguese patients comprising the entire spectrum of VWD types: impact of NGS

The diagnosis of von Willebrand disease (VWD), the most common inherited bleeding disorder, is characterised by a variable bleeding tendency and heterogeneous laboratory phenotype. The sequencing of the entire VWF coding region has not yet become a routine practice in diagnostic laboratories owing to its high costs. Nevertheless, next-generation sequencing (NGS) has emerged as an alternative to overcome this limitation. We aimed to determine the correlation of genotype and phenotype in 92 Portuguese individuals from 60 unrelated families with VWD; therefore, we directly sequenced VWF. We compared the classical Sanger sequencing approach and NGS to assess the value-added effect on the analysis of the mutation distribution in different types of VWD. Sixty-two different VWF mutations were identified, 27 of which had not been previously described. NGS detected 26 additional mutations, contributing to a broad overview of the mutant alleles present in each VWD type. Twenty-nine probands (48.3 %) had two or more mutations; in addition, mutations with pleiotropic effects were detected, and NGS allowed an appropriate classification for seven of them. Furthermore, the differential diagnosis between VWD 2B and platelet type VWD (n = 1), Bernard-Soulier syndrome and VWD 2B (n = 1), and mild haemophilia A and VWD 2N (n = 2) was possible. NGS provided an efficient laboratory workflow for analysing VWF. These findings in our cohort of Portuguese patients support the proposal that improving VWD diagnosis strategies will enhance clinical and laboratory approaches, allowing to establish the most appropriate treatment for each patient.

A two-step approach (Enzyme-linked immunosorbent assay and confirmation assay) to detect antibodies against von Willebrand factor in patients with Acquired von Willebrand Syndrome

BACKGROUND

Acquired von Willebrand Syndrome is a rare bleeding disorder, which arises in individuals with no personal or family history of bleeding, associated with lymphoproliferative and myeloproliferative disorders or other diseases.

AIM

To develop a two-step approach assay to detect autoantibodies against VWF and to verify their prevalence in AVWS.

METHODS

AVWS definition: negative personal or family history of bleeding diathesis, VWF below normal range and recent history of bleeding manifestations. Twenty-three consecutive patients affected by AVWS were enrolled. An ELISA assay (first step) using recombinant VWF protein immobilized on plates and sheep/goat polyclonal anti-human IgG or IgM labelled with peroxidase was developed. A group of 40 healthy subjects was tested to calculate the floating cut point value. A confirmation assay (with addition of purified VWF vs buffer) was performed (second step).

RESULTS

Twenty-one patients (93%) had an associated disease, two patients had idiopathic AVWS. Anti-VWF autoantibodies were detected in 9 patients (39%). Of these, eight (89%) had VWF:RCo levels <10%, but none of them resulted positive using Bethesda assay (neutralizing antibodies). The confirmation test confirmed the positive results obtained with ELISA and resulted negative in those patients with negative results and in the controls.

CONCLUSION

With the present two-step approach assay nine out of 23 (39%) patients affected with AVWS resulted positive for anti-VWF autoantibodies. This ELISA assay might be used as an additional confirmation tool in the diagnostic procedure in patients affected by AVWS or in the follow-up of congenital and acquired patients exposed to replacement therapy.

Third Åland islands conference on von Willebrand disease, 26-28 September 2012: meeting report

The first meeting of international specialists in the field of von Willebrand disease (VWD) was held in the Åland islands in 1998 where Erik von Willebrand had first observed a bleeding disorder in some members of a family from Föglö and a summary of the meeting was published in 1999. The second meeting was held in 2010 and a report of the meeting was published in 2012. Topics covered included progress in understanding of VWD over the last 50 years; multimers; classification of VWD; pharmacokinetics and laboratory assays; genetics; treating the paediatric patient; prophylaxis; geriatrics; gene therapy and treatment guidelines. This third meeting held over 3 days covered the structure and function of von Willebrand factor (VWF); type 1 VWD, the most common form of the disease; a lifespan of pharmacokinetics in VWD; detecting inhibitors in VWD patients; and special challenges in understanding and treating the female VWD patient.

Alloantibodies in von Willebrand disease

The development of alloantibodies against von Willebrand factor (VWF) represents a rare but serious complication of treatment of von Willebrand disease (VWD), occurring in ~5% to 10% of type 3 VWD patients. Affected patients can present with a range of symptoms, including lack or loss of hemostatic response to infused VWF concentrates up to anaphylactic reactions in rare cases. It is classically reported in multitransfused patients and occurs most frequently in patients with partial or complete VWF gene deletions. A positive family history of anti-VWF antibodies also appears to be a risk factor. There is a lack of standardization of laboratory methods for antibody identification and characterization. Issues of variability in laboratory approaches as well as the rarity of the complication act as a barrier to future studies. Recombinant factor VIII as well as bypassing agents and immune tolerance have been reported as effective treatments; however, aside from case reports, little exists in the literature to guide management. The imminent clinical availability of recombinant VWF has prompted a resurgence of interest in this area. Additional study is warranted to address the deficiencies in our understanding of this treatment complication.

Acquired von Willebrand syndrome associated with Hashimoto's thyroiditis and subcutaneous mucosa-associated lymphoid tissue lymphoma

Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder with laboratory findings similar to those of congenital von Willebrand disease. We herein report a case of AVWS associated with Hashimoto's thyroiditis and subcutaneous mucosa-associated lymphoid tissue lymphoma. An IgG autoantibody against von Willebrand factor (VWF) was detected. The antibody bound to VWF but did not inhibit VWF activity. Rapid clearance of VWF seemed to be the cause of AVWS in the present case. VWF-containing concentrates stopped the bleeding. Even if such a complication is rare, for AVWS patients, prompt recognition of the underlying mechanism can save lives.

Laboratory identification of factor inhibitors: an update

Coagulation factor inhibitors comprise antibodies that bind to and then neutralise specific pro-coagulant plasma proteins. Coagulation factor inhibitors can develop against any coagulation factor, although the most common are against factor VIII (FVIII). These can develop in individuals with inherited haemophilia A (HA) as an immune response to factor replacement therapy, or as auto-antibodies leading to the condition of acquired HA. Clinical suspicion for inhibitors may arise when individuals present with bleeding symptoms without any prior bleeding diathesis, or when a patient with known mild haemophilia presents with a bleeding diathesis more extreme to their usual presentation, or when there is failure of factor replacement therapy to arrest bleeding in a known haemophiliac. The laboratory identification of factor inhibitors requires a careful and systematic approach that excludes other possible causes of prolonged screening tests, most commonly the activated partial thromboplastin time (APTT), and sometimes prothrombin time (PT). Coagulation factor inhibitor studies, including the Bethesda assay, are then undertaken to measure inhibitor titre, which guides treatment. This paper overviews the laboratory investigation of factor inhibitors, and also briefly reviews recent cross-laboratory inhibitor studies and the most recent evidence related to differential inhibitor formation according to type of therapy.

Clinical and prognostic implications of low or high level of von Willebrand factor in patients with Waldenstrom macroglobulinemia

Acquired von Willebrand syndrome is described in patients with Waldenström macroglobulinemia (WM). Assessment of ristocetin cofactor activity (VWF:RCo) and von Willebrand factor (VWF) antigen (VWF:Ag) in 72 consecutive patients with WM showed a negative relation between VWF levels < 130 U/dL and both monoclonal immunoglobulin M concentration (mIgMC) and viscosity. Ten patients with VWF:RCo < 50 U/dL (< 40 for patients with blood group O) fulfilled the acquired von Willebrand syndrome criteria. They had higher mIgMC and viscosity. Reduction in mIgMC was associated with increase in VWF levels. The low VWF:RCo/VWF:Ag ratio suggested that high viscosity might be associated with increased shear force and cleavage of multimers. Surprisingly, 43 patients (59%) presented with high VWF:Ag (> 110 U/dL). They had higher bone marrow microvessel density and vascular endothelial growth factor expression on bone marrow mast cells. Five-year survival rates of patients with VWF:Ag < 110, between 110 and 250, and more than 250 U/dL were 96%, 71%, and 44%, respectively (P < .0001). High VWF:Ag was also a significant adverse prognostic factor for survival after first-line therapy (P < .0001), independently of the international scoring system. These results support systematic assessment of VWF in patients with WM. The adverse prognostic value of high VWF levels raises issues on interactions between lymphoplasmacytic cells, mast cells, and endothelial cells in WM.

Acquired von Willebrand syndrome associated with monoclonal gammopathy: a single-center study of 36 patients

In this single-center retrospective study, we evaluated the accuracy of laboratory tests in diagnosing acquired von Willebrand syndrome associated with lymphoproliferative disorders in 36 consecutive patients diagnosed at the University Hospital of Nantes, France. We also compared hemostatic treatments in the following groups: 21 patients with Waldenström macroglobulinemia (WM), 14 with monoclonal gammopathy of undetermined significance (MGUS) (10 with IgG-MGUS and 4 with IgM-MGUS), and 1 with IgA multiple myeloma (IgA-MM). The diagnosis was made in 18 (50%) patients during systematic screening, in 6 (17%) during active mild hemorrhage, and in 12 (33%) during an active, severe bleed. Of the laboratory tests studied, only closure times measured on the Platelet Function Analyzer (PFA)-100 device reliably diagnosed the hemostatic problem. There was no relationship between the factor VIII activity (FVIII:C) or von Willebrand factor activity (VWF:RCo) levels and the previous history of hemorrhage described by patients.We studied hemostatic treatment in most patients: IgG-MGUS patients responded well to high-dose intravenous immunoglobulin (IVIg) infusions (1 g/kg per d), although patients with IgM-MGUS did not. Desmopressin infusions were effective in 3 patients with IgG-MGUS and 2 patients with IgM-MGUS when the baseline values were above 10 IU/dL, but levels soon returned to the baseline. The 7 WM patients had a good response to desmopressin. These results confirm the efficacy of IVIg in IgG-MGUS patients and the prominent role of closure time in the diagnosis of acquired von Willebrand syndrome.

How I treat the acquired von Willebrand syndrome

The acquired von Willebrand syndrome (AVWS) is a bleeding disorder that is frequently unrecognized or is misdiagnosed as von Willebrand disease. AVWS is characterized by structural or functional defects of von Willebrand factor (VWF) that are secondary to autoimmune, lymphoproliferative or myeloproliferative, malignant, cardiovascular, or other disorders. VWF abnormalities in these disorders can result from (1) antibody-mediated clearance or functional interference, (2) adsorption to surfaces of transformed cells or platelets, or (3) increased shear stress and subsequent proteolysis. Diagnosis can be challenging as no single test is usually sufficient to prove or exclude AVWS. Furthermore, there are no evidence-based guidelines for management. Treatments of the underlying medical condition, including chemo/radiotherapy, surgery, or immunosuppressants can result in remission of AVWS, but is not always feasible and successful. Because of the heterogeneous mechanisms of AVWS, more than one therapeutic approach is often required to treat acute bleeds and for prophylaxis during invasive procedures; the treatment options include, but are not limited to, desmopressin, VWF-containing concentrates, intravenous immunoglobulin, plasmapheresis or recombinant factor VIIa. Here, we review the management of AVWS with an overview on the currently available evidence and additional considerations for typical treatment situations.

Prevalence, biological phenotype and genotype in moderate/mild hemophilia A with discrepancy between one-stage and chromogenic factor VIII activity

BACKGROUND

In most laboratories, the severity of hemophilia A is assessed by the factor VIII activity (FVIII:C) one-stage assay. However, comparisons of these results with those of two-stage assays can reveal discrepancies and suggest misdiagnosis.

PATIENTS/METHODS

In this monocentric study, we measured FVIII:C with two methods (one-stage chronometric and chromogenic assays) in 307 (173 families) patients with moderate/mild hemophilia A. To compare results, we used a chronometric/chromogenic ratio. Discrepancy was defined as a ratio < 0.5 or > 1.5. We studied their putative involvement at known FVIII functional sites, their interspecies conservation status, and their spatial position within the FVIII structure.

RESULTS

Thirty-six patients from 17 families exhibited a discrepancy between the two assays: 12 (6.9%) families had a low ratio (< 0.5), and five (2.9%) families had a high ratio (> 1.5). Qualitative deficiency was diagnosed in about 16% of the families. Molecular studies were performed in 15 of these 17 families, resulting in each case in the identification of missense mutations, including three novel mutations. We were further able to propose a pathophysiologic explanation.

CONCLUSIONS

In this monocentric study, we have demonstrated a discrepancy between FVIII:C assay results in 10% of families with moderate/mild hemophilia A. The prevalence of 'inverse' discrepancy (i.e. low chronometric/chromogenic ratio) is high as compared with previous reports. We suggest that both FVIII:C assays are recommended in patients with moderate/mild hemophilia A for a complete biological phenotype. This could also improve our knowledge of the FVIII structure-function relationships.

[Three cases of IgM monoclonal gammopathy with haemostasis dysfunction]

We relate three cases of IgM gammopathy with haemostatic dysfunction in the perioperative period. The acquired von Willebrand syndrome due to IgM gammopathy is rare and sometimes serious. Its different treatments and their efficiency are discussed: desmopressin, intravenous gammaglobulin, chemotherapy and plasmapheresis.

Mechanisms underlying acquired von Willebrand syndrome associated with an IgM paraprotein

Acquired von Willebrand (vW) syndrome is a rare bleeding disorder which is frequently associated with immunological, malignant or cardiovascular disorders. The underlying pathomechanisms, particularly in patients with IgM monoclonal gammopathies, often remain unknown. We report a patient with indolent small B-cell lymphoma (immunocytoma) and plasmacytic differentiation with an IgM kappa paraprotein who was admitted with retroperitoneal haematoma. Medical history and coagulation testing were consistent with acquired vW syndrome. vW immunohistochemistry showed normal cytoplasmic labelling of endothelial cells and megakaryocytes, whereas the lymphomatous infiltrate was negative. Acquired vW syndrome due to adsorption of vW factor on malignant cells was thus excluded. In the multimeric analysis, all multimers were present similar to that in type 1 vW syndrome, but the triplet structures were blurred. The bands on serum immunofixation electrophoresis were also atypically broadened, which suggested complex formation between the IgM and vW factor. Immunoprecipitation studies showed that the 176-kDa proteolytic fragment of vW factor co-precipitated with the IgM paraprotein in the patient but not in the controls, suggesting a specific interaction between vW factor and the paraprotein in the patient. The patient required surgery and was successfully managed by chemotherapy consisting of rituximab and fludarabin as well as plasma exchange.

[Acquired von Willebrand syndrome: from diagnosis to treatment]

Acquired von Willebrand syndrome is a rare bleeding disorder, which has been related in various diseases including lymphoproliferative disorders or autoimmune diseases. Its diagnosis is an important step before treatment of patients and particularly in case of bleeding. We report four cases from Caen Hemophilia Treatment Center, diagnosed and treated from 1999 to 2008. Mucocutaneous bleeds in every case were the same as in hereditary von Willebrand disease. All patients had no personal or family history of bleeding. Phenotype was identified as type 2 von Willebrand disease with a loss of high molecular weight multimers. Anti-von Willebrand factor inhibitor screening was positive for three patients. The etiological diagnosis was one chronic lymphocytic leukaemia, two monoclonal gammapathies of undetermined significance (MGUS) and one undetermined case. The management of patients need two stages: first infusions of factor von Willebrand/factor VIII concentrates to stop bleeds, then treatment of the underlying disease such as chemotherapy, corticotherapy and treatment with high doses of polyvalents immunoglobulins. In every case, treatment was effective and improved patient's quality of life.

Pathogenesis and management of bleeding and thrombosis in plasma cell dyscrasias

Unexpectedly high rates of venous thromboembolic events (VTE) concurrent with the introduction of highly effective immune modulating drugs thalidomide and lenolidomide for treatment of multiple myeloma have focused attention on the incidence and underlying pathophysiology of VTE in patients with plasma cell dyscrasias, and on thromboprophylaxis approaches. While bleeding complications are relatively uncommon in patients with lymphoproliferative disorders, acquired von Willebrand syndrome, typically occurring in patients with monoclonal gammopathy of unknown significance, and acquired coagulopathies associated with primary amyloidosis can present with haemorrhagic complications and both are challenging to manage. This review highlights these important haemostasis-related complications of plasma cell dyscrasias and provides an overview of other uncommon bleeding and thrombotic events that can affect diagnostic and therapeutic management of clonal plasma cell disorders. Due to the infrequency of most of these haemostasis complications, available information is typically based on retrospective cases or series.

The Role Of von Willebrand Factor In Hemorrhagic And Thrombotic Disorders

von Willebrand factor (VWF) is a multimeric plasma protein that mediates platelet adhesion as well as platelet aggregation at sites of vascular injury and acts as a carrier of factor VIII. Although acquired or inherited VWF deficiency is associated with a bleeding tendency, there is increasing evidence that VWF has a pivotal role in thrombogenesis. In fact, while the presence in the plasma of unusually large VWF multimers, due to a congenital or acquired deficiency of a VWF-cleaving metalloprotease, has been implicated in the pathogenesis of thrombotic thrombocytopenic purpura, high plasma levels of VWF have been associated with an increased risk of both arterial and venous thrombosis. The role of VWF in normal and pathological hemostasis is discussed in this review, and important advances in the pathophysiology, diagnosis, and treatment of VWF-associated disorders are also described.

Systemic lupus erythematosus complicated by acquired von Willebrand’s syndrome

Haematological abnormalities are common in systemic lupus erythematosus (SLE). In some cases of acquired von Willebrand syndrome (AvWS), von Willebrand disease (vWD) is associated with autoimmune or lymphoproliferative disorders. In this study, we describe a 36-year-old woman with SLE and AvWS. The patient was referred to our hospital because of easy bruisability and recurrent vaginal bleeding. She had no history of bleeding tendency and no family history of bleeding diathesis, but she had a history of recurrent arthralgia, photosensitivity and sicca symptoms. Tests for antinuclear, anti–double stranded DNA, anticardiolipin and anti–β2-glycoprotein I antibodies were all positive. Analysis of haemostatic parameters showed complete absence of von Willebrand factor ristocetin cofactor (vWF:Rco), von Willebrand antigen (vWF:Ag) and ristocetin-induced platelet aggregation (RIPA). Electrophoretic analysis of plasma showed a complete absence of high–molecular weight vWF multimer. The presence of antibody to vWF was detected by enzyme linked immunosorbent assay (ELISA). Treatment with corticosteroids improved SLE symptoms and corrected bleeding diasthesis. Also, the multimeric patterns of vWF became normalised and anti–vWF antibody disappeared. These findings indicated that this patient had SLE associated with AvWS, which was ameliorated by corticosteroid treatment.

Diagnostic workup of patients with acquired von Willebrand syndrome: a retrospective single-centre cohort study

BACKGROUND

Diagnosis of acquired von Willebrand syndrome (AVWS) remains challenging. Diagnostic algorithms suggest the use of factor VIII (FVIII:C), von Willebrand factor antigen (VWF:Ag), ristocetin cofactor (VWF:RCo), and collagen-binding capacity (VWF:CB), but the sensitivity of these and other laboratory tests for the diagnosis of AVWS is unknown.

OBJECTIVES

To analyze the capacity of laboratory tests, including point-of-care testing (POCT), for the identification of patients with AVWS.

PATIENTS/METHODS

Thirty-five consecutive patients were enrolled with AVWS diagnosed because of a history of recent onset of bleeding, a negative family history of von Willebrand disease, and abnormal plasma VWF multimers.

RESULTS

According to our inclusion criteria, all patients had bleeding symptoms, and the VWF high molecular weight multimers were either decreased or absent. Regarding POCT, PFA-100 was inconclusive, due to anemia or thrombocytopenia, in 29%; the sensitivity was 80% in the remaining patients. The sensitivity of VWF:Ag (23%), VWF:RCo/Ag ratio < 0.7 (26%), VWF:CB/Ag ratio < 0.7 (46%), anti-VWF antibodies (15%) and VWF propeptide/Ag ratio (22%) was too low to rule out the disease. A combination of VWF:Ag < 50 IU dL(-1), VWF:RCo/Ag ratio < 0.7 and VWF:CB/Ag ratio < 0.8 yielded a sensitivity of 86%. Patients diagnosed only because of abnormal VWF multimers showed similar clinical characteristics as other patients.

CONCLUSIONS

Early diagnosis of AVWS is difficult, due to lack of sensitivity of the tests used. A substantial number of patients present with normal or increased test results, emphasizing the importance of multimer analysis in all patients with suspected AVWS.

Acquired von Willebrand syndrome: an update

Acquired von Willebrand syndrome (aVWS) is a rare bleeding disorder with laboratory findings similar to those for congenital von Willebrand disease (VWD). However, unlike congenital VWD, it arises in individuals with no personal or family history of bleeding. aVWS occurs in association with a variety of underlying disorders, most frequently in lymphoproliferative disorders, myeloproliferative disorders, and cardiovascular diseases. Through an analysis of the more recent literature data, the pathophysiology and the clinical, laboratory, and therapeutic aspects of this syndrome are concisely reported in this review.

Recent acquisitions in acquired and congenital von Willebrand disorders

von Willebrand factor is a multimeric plasma protein that mediates platelet adhesion as well as platelet aggregation at sites of vascular injury and, moreover, acts as a carrier of factor VIII. Its deficiency is associated with a bleeding tendency. The progresses in the pathophysiology, diagnosis and management of inherited von Willebrand disease and acquired von Willebrand syndrome will be discussed in this review.

Bleeding and Thrombosis Risks in Plasma Cell Dyscrasias

Major, spontaneous bleeding is uncommon in patients with plasma cell dyscrasias despite frequent abnormal screening hemostasis tests. However, acquired von Willebrand deficiency and light-chain (AL) amyloidosis, and amyloidosis complicating multiple myeloma can present with serious hemorrhagic complications that are challenging to manage. While patients with monoclonal gammapathy of undetermined significance and multiple myeloma share an intrinsic increased risk of venous thromboembolic events (VTE), treatment with thalidomide and lenalidomide increases the incidence of VTE in certain multiple myeloma patient subsets. Our understanding of the complex interactions among malignant plasma cells, inflammatory and hemostasis pathways, and treatment modalities that combine to produce thrombotic complications is incomplete. Prospective, randomized trials are clearly needed to assist clinicians in providing optimal VTE prophylaxis to their patients with plasma cell dyscrasias.

Acquired von Willebrand syndrome: diagnostic problems and therapeutic options

We present a case of acquired von Willebrand syndrome (AVWS) due to a monoclonal gammopathy of undetermined significance. Initially this case was diagnosed as congenital von Willebrand disease (VWD); however, re-examination of the medical history rendered a congenital bleeding disorder unlikely. A normal plasma von Willebrand factor (VWF) propeptide level and a very short half-life of VWF after a test infusion with factor VIII/VWF concentrate confirmed the diagnosis AVWS. Two major surgical procedures were successfully managed using high-dose intravenous immunoglobulin. The differential diagnosis with congenital VWD and the diagnostic and therapeutic approaches of AVWS are discussed. We conclude that the diagnosis of AVWS relies primarily on clinical suspicion and a careful bleeding history. A correct diagnosis is essential for optimal perioperative management and treatment of bleeding episodes.

Acquired von Willebrand syndrome in a patient with Ewing sarcoma

Acquired von Willebrand syndrome is a rare bleeding disorder with clinical and laboratory features closely resembling to hereditary von Willebrand disease. The syndrome may accompany various conditions, including malignant disorders, most often with Wilms tumor and adrenal cell carcinoma. In this report, the authors present a patient with AvWS in association with Ewing sarcoma for the first time in the literature. The abnormal bleeding tendency was successfully treated with fresh frozen plasma and did not recur after the first two courses of chemotherapy with clinical improvement.

Acquired von Willebrand Syndrome: An Underdiagnosed and Misdiagnosed Bleeding Complication in Patients With Lymphoproliferative and Myeloproliferative Disorders

Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder with laboratory findings similar to those for congenital von Willebrand disease (VWD). Unlike the congenital disease, AVWS usually occurs in individuals with no personal or family history of bleeding. The prevalence of AVWS in the general population is unknown because data from large prospective studies of this syndrome are not available. Although AVWS is particularly frequent in lymphoproliferative or myeloproliferative disorders, it can also be associated with solid tumors, immunologic and cardiovascular disorders, and other miscellaneous conditions. Diagnosis of AVWS is based on assays measuring the activity of von Willebrand factor (VWF). This tends to be abnormally low, but factor VIII (FVIII) coagulant activity can sometimes be normal. FVIII/VWF inhibiting activity is found in only a minority of cases. Bleeding episodes in patients with AVWS are mostly of the mucocutaneous type and can be managed with desmopressin, plasma-derived FVIII/VWF concentrates, and intravenous immunoglobulin (IVIg). Recombinant activated factor VII can be useful in patients unresponsive to standard therapy. An updated version of the International Registry on AVWS, recently available online, will provide more information on this rare, but underdiagnosed and misdiagnosed, disorder.

Use of Intravenous Immunoglobulin in Patients With Acquired von Willebrand Syndrome

Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder with laboratory findings similar to those for congenital von Willebrand disease. Unlike the congenital form, AVWS usually occurs in individuals with no personal or family history of bleeding disorders. According to an international registry, AVWS is mainly associated with lymphomyeloproliferative, immunologic, and cardiovascular disorders, as well as with solid tumors and other miscellaneous conditions; however, the prevalence of AVWS in these underlying disorders is still unknown. von Willebrand factor (VWF) is synthesized normally in most AVWS patients, and the low plasma VWF levels are from its accelerated removal from plasma by five different mechanisms, including autoantibodies. Because of the reduced half-life of endogenous-exogenous plasma VWF, bleeding of AVWS cannot be managed with desmopressin or factor VIII/VWF concentrates. Clinical use of intravenous immunoglobulin (IVIg) in AVWS has been reported since 1988. IVIg is most effective in AVWS with type immunoglobulin (Ig) G monoclonal gammopathies of undetermined significance and in other cases with IgG autoantibodies. IVIg can correct factor VIII and von Willebrand factor complex activities for about 15-20 days, and repeated injections induce remission of AVWS in these patients. Prospective studies are required to evaluate the efficacy and safety of IVIg in AVWS.