The management of von Willebrand's disease-associated gastrointestinal angiodysplasia

Special considerations in GI bleeding in VWD patients

Gastrointestinal (GI) bleeding is an important cause of morbidity and mortality in von Willebrand disease (VWD). It has been noted that GI bleeding caused by angiodysplasia is overrepresented in VWD patients compared to other causes. The bleeding from angiodysplasia is notoriously difficult to treat; recurrences and rebleeds are common. A growing body of basic science evidence demonstrates that von Willebrand factor negatively regulates angiogenesis through multiple pathways. VWD is clinically highly associated with angiodysplasia. The predisposition to angiodysplasia likely accounts for many of the clinical difficulties related to managing GI bleeding in VWD patients. Diagnosis and treatment are challenging with the current tools available, and much further research is needed to further optimize care for these patients with regard to acute treatment, prophylaxis, and adjunctive therapies. In this review we provide an overview of the available literature on GI bleeding in VWD and explore the molecular underpinnings of angiodysplasia-related GI bleeding. Considerations for diagnostic effectiveness are discussed, as well as the natural history and recurrence of these lesions and which therapeutic options are available for acute and prophylactic management.

Gastrointestinal Bleeding in Congenital Bleeding Disorders

Gastrointestinal bleeding (GIB) is serious, intractable, and potentially life-threatening condition. There is considerable heterogeneity in GIB phenotypes among congenital bleeding disorders (CBDs), making GIB difficult to manage. Although GIB is rarely encountered in CBDs, its severity in some patients makes the need for a comprehensive and precise assessment of underlying factors and management approaches imperative. Initial evaluation of GIB begins with assessment of hematological status; GIB should be ruled out in patients with chronic anemia, and in presentations that include hematemesis, hematochezia, or melena. High-risk patients with recurrent GIB require urgent interventions such as replacement therapy for treatment of coagulation factor deficiency (CFD). However, the best management strategy for CFD-related bleeding remains controversial. While several investigations have identified CBDs as potential risk factors for GIB, research has focused on assessing the risks for individual factor deficiencies and other CBDs. This review highlights recent findings on the prevalence, management strategies, and alternative therapies of GIB related to CFDs, and platelet disorders.

Vascular abnormalities in patients with von Willebrand disease: A scoping review

BACKGROUND

Qualitative or quantitative defects of von Willebrand factor (VWF) such as in von Willebrand disease (VWD) are associated with vascular abnormalities, especially in the gastrointestinal (GI) tract. However, the locations, extent, and natural history of vascular abnormalities in patients with VWD is not well understood. To summarize the existing literature on the topic, we conducted a scoping review of vascular abnormalities in patients with VWD.

METHODS

We searched MEDLINE and EMBASE from inception to September 1, 2020, for studies clinically describing vascular abnormalities in VWD patients. Screening and data extraction was completed independently and in duplicate and each abnormality was documented individually.

RESULTS

After screening, 54 studies that reported patient level data comprising 146 patients were included. Type 2A (39%) and type 3 (14.4%) were the most common VWD subtypes. The most common site of vascular malformation was the GI tract, occurring in 124 patients (84.9%), whereas 18 (12.3%) had non-GI vascular abnormalities and 4 (2.7%) had both GI and non-GI vascular abnormalities. With respect to outcomes, the clinical course was not specified in the majority (55.5%) of patients. Survey and population level data were reported in nine studies, demonstrating vascular abnormalities occurred at higher rates in VWD and that VWD patients are overrepresented among those with those abnormalities.

CONCLUSION

Vascular malformations in patients with VWD occur primarily in the gastrointestinal tract. Type 2A and type 3 VWD are the most common subtypes affected. The clinical treatment and natural history of these abnormalities remains understudied and further research is needed.

Gastrointestinal angiodysplasia and bleeding in von Willebrand disease

Von 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.

Angiodysplasia in von Willebrand Disease: Understanding the Clinical and Basic Science

Severe and intractable gastrointestinal bleeding caused by angiodysplasia is a debilitating problem for up to 20% of patients with von Willebrand disease (VWD). Currently, the lack of an optimal treatment for this recurrent problem presents an ongoing challenge for many physicians in their management of affected patients. Over the past few years, studies have pointed to a regulatory role for the hemostatic protein, von Willebrand factor (VWF), in angiogenesis, providing a novel target for the modulation of vessel development. This article will review the clinical implications and molecular pathology of angiodysplasia in VWD.

How I treat type 2 variant forms of von Willebrand disease

Type 2 von Willebrand disease (VWD) includes a wide range of qualitative abnormalities of von Willebrand factor structure and function resulting in a variable bleeding tendency. According to the current classification, 4 different subtypes can be identified, each with distinctive phenotypic and therapeutic characteristics. Current available laboratory methods allow a straightforward approach to VWD subtyping, and although the precise molecular characterization remains complex, it is not required for appropriate treatment of the vast majority of cases. Desmopressin can be useful only in a few type 2 cases compared with patients with actual quantitative deficiency (type 1), most often in variants with a nearly normal multimeric pattern (type 2M). However, since no laboratory test accurately predicts response to desmopressin, a trial test should always be performed in all type 2 VWD patients, with the exception of type 2B ones. Replacement therapy with plasma-derived von Willebrand factor-factor VIII concentrates represents the safe mainstay of treatment of all patients, particularly those not responding to desmopressin or requiring a sustained hemostatic correction because of major surgery or bleeding. A significant patient bleeding history correlates with increased bleeding risk and should be considered in tailoring the optimal antihemorrhagic prophylaxis in the individual patient.

The natural history of occult or angiodysplastic gastrointestinal bleeding in von Willebrand disease

Recurrent gastrointestinal bleeding is one of the most challenging complications encountered in the management of patients with von Willebrand disease (VWD). The commonest cause is angiodysplasia, but often no cause is identified due to the difficulty in making the diagnosis. The optimal treatment to prevent recurrences remains unknown. We performed a retrospective study of VWD patients with occult or angiodysplastic bleeding within the setting of the von Willebrand Disease Prophylaxis Network (VWD PN) to describe diagnostic and treatment strategies. Centres participating in the VWD PN recruited subjects under their care with a history of congenital VWD and gastrointestinal (GI) bleeding due to angiodysplasia, or cases in which the cause was not identified despite investigation. Patients with acquired von Willebrand syndrome or those for whom the GI bleeding was due to another cause were excluded. Forty-eight patients from 18 centres in 10 countries were recruited. Seven individuals had a family history of GI bleeding and all VWD types except 2N were represented. Angiodysplasia was confirmed in 38%, with video capsule endoscopy and GI tract endoscopies being the most common methods of making the diagnosis. Recurrent GI bleeding in VWD is associated with significant morbidity and required hospital admission on up to 30 occasions. Patients were treated with multiple pharmacological agents with prophylactic von Willebrand factor concentrate being the most efficient in preventing recurrence of the GI bleeding. The diagnosis and treatment of recurrent GI bleeding in congenital VWD remains challenging and is associated with significant morbidity. Prophylactic treatment with von Willebrand factor concentrate was the most effective method of preventing recurrent bleeding but its efficacy remains to be confirmed in a prospective study.

Von Willebrand disease-associated angiodysplasia: a few answers, still many questions

The association between angiodysplasia and von Willebrand disease (VWD) has been known for more than 40 years. Bleeding in the gastrointestinal tract associated with angiodysplasia worsens the clinical course of this inherited haemorrhagic disorder and management may become difficult and challenging. Angiodysplasia associated with acquired defects or dysfunctions of von Willebrand factor (VWF) has also been reported in a variety of conditions such as monoclonal gammopathies, Heyde syndrome and in carriers of ventricular assist devices. The most recent advances concerning the mechanistic, clinical and therapeutic aspects of VWD-associated angiodysplasia are summarized in this review, together with the limitations of our knowledge that warrant further research in the frame of international cooperation.

Different bleeding risk in type 2A and 2M von Willebrand disease: a 2-year prospective study in 107 patients

BACKGROUND

Type 2A and 2M von Willebrand disease (VWD2A and VWD2M) are characterized by the presence of a dysfunctional von Willebrand factor (VWF) and a variable bleeding tendency. So far, a head-to-head comparison of the clinical history and bleeding risk between VWD2A and VWD2M has never been provided in a prospective manner.

AIM OF THE STUDY

We assessed the bleeding incidence rate and clinical characteristics in two cohorts of 17 families (46 patients) with VWD2A and 15 families (61 patients) with VWD2M prospectively followed-up for 24 months. VWF gene mutations were characterized in all of them.

RESULTS

Mean bleeding score (BS) and VWF antigen at enrollment were significantly higher in VWD2A patients (P = 0.007). No correlation between VWF activity or factor VIII levels and the severity of BS was observed. The incidence rate of spontaneous bleeding requiring treatment was 107/100 patient-years (95% CI, 88.3-131) in VWD2A compared with 40/100 patient-years (95% CI, 30-53) in VWD2M (P < 0.001). The risk of bleeding was significantly higher in patients with BS ≥ 10 at enrollment compared with those with BS 0-2. Furthermore, 54 episodes of gastrointestinal bleeding occurred in 17/46 (36.9%) VWD2A patients and seven in 2/61 (3.3%) VWD2M patients (P < 0.0001).

CONCLUSION

Bleeding tendency in VWD2A is greater than that of VWD2M, is not explained by factor VIII or VWF levels and is mainly due to an increased incidence of gastrointestinal bleeding.

The evaluation and management of obscure and occult gastrointestinal bleeding

Gastrointestinal (GI) bleeding is a common clinical presentation increasing in an aging population, frequently requiring hospitalization and emergent intervention, with significant morbidity, mortality, and costs. It may manifest overtly as hematemesis, melena, or hematochezia, or as an asymptomatic occult bleed. Management typically involves an esophagogastroduodenoscopy or a colonoscopy; these in combination sometimes do not identify a source of bleeding, with the source remaining obscure. Further work up to identify an obscure source frequently requires radiologically detecting the leakage of an intravascular tracer (using tagged red blood cells or angiography) with brisk bleeding or in other cases CT enterography (CTE) to detect bowel wall changes consistent with a bleeding source. Recent advances including capsule endoscopy, CTE, and double-balloon endoscopy have helped to identify bleeding sources beyond the reach of conventional endoscopy. Clinical decision-making about their use is complex and evolving. Knowing their relative merits and weaknesses including yield, contraindications, complications, and cost is essential in coming up with an appropriate management plan. This review covers the rationale for clinical management of obscure sources of GI bleeding, mentioning the approach to and the yield of conventional methods, with an emphasis on the recent advances mentioned above.

Prophylaxis in von Willebrand disease

This paper reviews current issues regarding short-term (i.e. for surgery and invasive procedures) and long-term (i.e. regular infusions to prevent bleeding on a permanent or temporary basis) prophylaxis treatment using replacement concentrates for patients with von Willebrand disease (VWD) who do not respond satisfactorily to desmopressin. The standard treatment of these patients is with factor concentrates containing von Willebrand factor (VWF) and factor VIII (FVIII). When dosing these concentrates, the broad variations in content and quality of VWF as well as the FVIII content in the products should be considered. Peri-operative management strategies will depend on the VWD subtype, baseline VWF and FVIII levels, and size of procedure. FVIII level and VWF ristocetin cofactor activity may both be used to determine concentrate potency and to monitor treatment. Long-term prophylaxis, which has become a state-of-the-art approach in haemophilia, is not very common in VWD. However, more recent data suggest that a substantial number of VWD patients could benefit from prophylactic treatment with VWF-containing concentrates. For example, 35 Swedish VWD patients who required prophylaxis (mainly because of nose/mouth bleeds and joint bleeds) showed a substantial overall reduction in bleeding episodes and there were no signs of arthropathy in children who began prophylaxis before the age of 5 years since initiation of treatment with Haemate P/Humate-P. Studies of prophylaxis in VWD are urgently needed to develop evidence-based guidelines for this approach; the VWD International Prophylaxis study, for example, has commenced by the VWD Prophylaxis Network.

American Gastroenterological Association (AGA) Institute technical review on obscure gastrointestinal bleeding

This literature review and the recommendations therein were prepared for the AGA Institute Clinical Practice and Economics Committee. The paper was approved by the Committee on March 12, 2007, and by the AGA Institute Governing Board on May 19, 2007.

Diagnostic and therapeutic difficulties in type 2A von Willebrand disease: resolution

A patient with type 2A von Willebrand disease and a long history of gastrointestinal (GI) bleeding is presented, in whom no abnormality was found on sequencing the von Willebrand factor gene at the DNA level. Subsequent RNA analysis revealed him to be heterozygous for a T-C substitution at nucleotide 4,883, a mutation previously described and associated with type 2A von Willebrand disease. This illustrates the value of a dual DNA/ RNA approach to genetic investigations of highly polymorphic genes. GI bleeding from angiodysplasia is a feature of von Willebrand disease, particularly type 2A. Proactive management with definitive diagnosis of angiodysplasia and ablative treatment where feasible is recommended to stop bleeding symptoms and minimize exposure to blood products.

Small Bowel Angiodysplasia Associated with von Willebrand's Disease: Report of a Case

The association between angiodysplasia (AD) and von Willebrand's disease (vWD) was first described by Quick in 1967. The clinical course of patients with vWD and AD is characterized by multiple admissions to hospital for gastrointestinal bleeding, necessitating transfusions of packed red cells, factor VIII, and von Willebrand factor concentrates. The therapeutic management of these patients is difficult. Both medical and endoscopic techniques have been tried, but no treatment modality has been completely successful. We describe the clinical course of a patient affected by vWD, who suffered repeated massive gastrointestinal bleeding caused by small bowel AD. Intestinal resection was the only effective treatment, resulting in complete remission of the gastrointestinal bleeding.

Gastrointestinal bleeding in von Willebrand disease

Gastrointestinal bleeding due to colonic angiodysplasia is a well-recognised complication of von Willebrand disease (vWD), occurring almost exclusively in subtypes of the disease associated with a reduction in high-molecular-weight (HMW) multimers of von Willebrand factor (vWF). A deficiency of vWF HMW multimers also provides the link between aortic stenosis and gastrointestinal (GI) bleeding in Heyde's syndrome. The diagnosis and treatment of the angiodysplastic bleeding in vWD can be very difficult and the role of vWF containing concentrates in treatment and prophylaxis remains to be established.

Efficacy of Haemate-P as prophylaxis of recurrent bleeding in a patient with type 2B von Willebrand's disease

We report the case of a 58-year-old woman with type 2B von Willebrand's disease who received regular infusions of the factor VIII/von Willebrand factor concentrate Haemate-P (2000 IU every other day) for 4 months to prevent recurrent bleeding from a malignant esophageal ulcer. Prophylaxis with Haemate-P was shown to be safe and effective in this patient, thus enabling completion of radiochemotherapy.

Gastrointestinal angiodysplasia in a patient with type 2 von Willebrand's disease and analysis of exon 28 of the von Willebrand factor gene

Although the association between gastrointestinal angiodysplasia and von Willebrand's disease has been suggested, molecular mechanisms involved in the formation of angiodysplasia in patients with von Willebrand's disease remained undetermined. We examined exon 28 of the von Willebrand factor gene in a patient with both von Willebrand's disease and recurrent bleeding from angiodysplasia in the duodenum as well as his father's, and found a point mutation, C 3916-->T (amino acid substitution; Arg 543-->Trp), in the A1 domain of the von Willebrand factor gene. This mutation was identical with a previously reported mutation in a patient with von Willebrand's disease complicated with gastrointestinal angiodysplasia.

Gastrointestinal bleeding, angiodysplasia, cardiovascular disease, and acquired von Willebrand syndrome

Recent evidence points to isolated deficiency of the largest multimers of von Willebrand factor (VWF)-known as von Willebrand syndrome type 2A (VWS-2A)-as a risk factor for bleeding from gastrointestinal (GI) angiodysplasia. This disorder is not widely recognized, perhaps because most patients do not exhibit generalized hemostatic impairment (bleeding is generally restricted to GI angiodysplasia) and because all but the largest multimers of VWF remain detectable in the plasma (thus, routine screening tests for VWS-2A are usually normal). The "Rosetta stone" for elucidating this syndrome was the enigma of Heyde's syndrome (aortic stenosis plus bleeding GI angiodysplasia), particularly the striking observation that aortic valve replacement generally cures GI bleeding and that preoperative deficiency of the largest VWF multimers undergoes long-term normalization after valve replacement. We critically review the evidence implicating VWS-2A as a risk factor for bleeding GI angiodysplasia. We hypothesize that VWS-2A secondary to cardiovascular disease other than severe aortic stenosis, such as peripheral arterial occlusive disease, could explain why elderly patients often develop recurrent GI bleeding or iron deficiency anemia from GI angiodysplasia.

Early transfusion of factor VIII/von Willebrand factor concentrates seems to be effective in the treatment of gastrointestinal bleeding in patients with von Willebrand type III disease

The association between gastrointestinal angiodysplasia and von Willebrand disease was reported 30 years ago. The clinical course of patients with von Willebrand disease and angiodysplasia is characterized by numerous admissions to hospital for gastrointestinal bleeding necessitating transfusion with packed red cells, factor VIII and plasma. The management of these patients is problematic. Numerous treatments for the gastrointestinal bleeding have been proposed: surgery, electrocoagulation, laser photocoagulation, sclerotherapy, arteriography with embolization, immunoglobulins, oestrogens, and octreotide, but no treatment modality has been successful in all cases. We report a 66-year-old-female with small bowel angiodysplasia and von Willebrand type III disease in whom prompt administration of factor VIII/vWF concentrates was effective. Education of patients to recognize minimal gastrointestinal bleeding manifestations, periodical clinical visits and early infusion of factor VIII/vWF seems to be fundamental for the success of this therapy. A longer follow-up and the study of other patients are needed to confirm our observation.