Association of acquired von Willebrand syndrome with AL amyloidosis

Immunoglobulin Light Chain Amyloidosis: Diagnosis and Risk Assessment

Immunoglobulin light chain (AL) amyloidosis is a clonal plasma cell disorder with multiple clinical presentations. The diagnosis of AL amyloidosis requires a high index of suspicion, making a delay in diagnosis common, which contributes to the high early mortality seen in this disease. Establishing the diagnosis of AL amyloidosis requires the demonstration of tissue deposition of amyloid fibrils. A bone marrow biopsy and fat pad aspirate performed concurrently have a high sensitivity for the diagnosis of AL amyloidosis and negate the need for organ biopsies in most patients. An accurate diagnosis requires amyloid typing via additional testing, including tissue mass spectrometry. Prognostication for AL amyloidosis is largely driven by the organs impacted. Cardiac involvement represents the single most important prognostic marker, and the existing staging systems are driven by cardiac biomarkers. Apart from organ involvement, plasma cell percentage on the bone marrow biopsy, specific fluorescence in situ hybridization findings, age at diagnosis, and performance status are important prognostic markers. This review elaborates on the diagnostic testing and prognostication for patients with newly diagnosed AL amyloidosis.

Severe bleeding diathesis as onset of light-chain amyloidosis: combined excessive fibrinolysis and acquired von Willebrand disease in a young patient

Our report shows a case of primary light-chain amyloidosis in a young patient that reflects the potential severity of bleeding diathesis associated with this plasma cell dyscrasia and the difficulty of diagnosis when only hemorrhagic manifestations are present at the onset of disease. The patient presented with recurrent and severe muscular bleeding secondary to associated acquired von Willebrand disease and fibrinolysis dysfunction. Treatment with bortezomib-cyclophosphamide and sequential hematopoietic stem cell transplantation solved coagulation alterations. On the basis of our case, we review previous reports and discuss the potential mechanism of dysfunction of coagulation in light-chain amyloidosis.

Acquired von Willebrand syndrome and lymphoid neoplasms: A review of malignancy management, and propositions of practical recommendations

INTRODUCTION

Acquired von Willebrand syndrome (AWS) is a rare and potentially life-threatening bleeding disorder. AWS is primarily associated with lymphocyte-related disorders (AWS-LRD), such as lymphoma and IgM monoclonal gammopathy of undetermined significance (MGUS), and plasmocyte-related disorders (AWS-PRD), such as non-IgM MGUS and myeloma. Symptomatic treatments are important to control and prevent bleeding, but AWS-LRD and AWS-PRD can only be cured by targeting the responsible clonal cell. No reviews exist on this specific subgroup of AWS.

AIM

We performed a literature review to help manage these rare cases.

METHOD

Thirty-two AWS-PRD and 43 AWS-LRD cases with data on malignancy treatment were reported in 56 articles from the Medline database.

RESULTS

LRDs were exclusively indolent and primarily associated with IgM monoclonal compounds. LRDs and PRDs may be treated because of severe bleeding symptoms, but severe VWF deficiency did not necessarily correlate with severe bleeding. Immunosuppressive drugs in AWS-PRD, including rituximab, provided an overall response rate of AWS (AWS-ORR) of 30% (3/10), including short responses. Anti-myeloma drugs provided an AWS-ORR of 71.4% (20/28), with long-lasting remissions. Bortezomib was the most commonly used drug and provided an AWS-ORR of 66.7% (6/9), including therapeutic associations with other anti-myeloma drugs. Autologous and allogeneic stem cell transplantation was performed in eight and two patients, respectively, and some details on the management of AWS during these procedures were provided. Rituximab in AWS-LRD provided an AWS-ORR of 60% (3/5), and a chemotherapy + rituximab regimen increased the AWS-ORR to above 50%. Bleeding syndrome in AWS-PRD and AWS-LRD generally improved prior to AWS biological improvement.

CONCLUSION

Long term remission of AWS due to lymphoid neoplasms is attainable by treating the underlying clonal cell. Some data and recommendations are provided to help answer difficult questions, including treatment timing, choice of drug, and the timing of evaluations and treatment changes.

Treatment of Patients with Monoclonal Gammopathy of Clinical Significance

Simple Summary

Monoclonal gammopathy of clinical significance (MGCS) is a recently recognized clinical-pathological entity. Symptoms are caused by the presence of a monoclonal protein leading to high comorbidity. The affected organs vary according to the target antigen However, as most of the knowledge relies on case reports or short series; there is a lack of consensus regarding treatment approach. Here, we discuss MGCS other than renal (skin, ocular, neurologic, and bleeding disorders). We provide insights into the pathophysiology, diagnosis, treatment, and follow-up based on clinical cases. Finally, we discuss future directions in this field, such as potential novel therapeutic targets and prognosis of patients with MGCS.

Abstract

Monoclonal gammopathy of undetermined significance (MGUS) is defined as the presence of a monoclonal protein (M-protein) produced by a small amount of plasma cells. The majority of patients remain asymptomatic; however, a fraction of them develop clinical manifestations related to the monoclonal gammopathy despite not fulfilling criteria of multiple myeloma or other lymphoproliferative disorder. These patients constitute an emerging clinical issue coined as monoclonal gammopathy of clinical significance (MGCS). The mechanisms involved are poorly understood, and literature is scarce regarding management. The clinical spectrum involves symptoms related to renal, neurologic, skin, ocular, or bleeding manifestations, requiring a multidisciplinary approach. Treatment strategies rely on the basis of symptomatic disease and the M-protein isotype. In this review, we focus on MGCS other than renal, as the latter was earliest recognized and better known. We review the literature and discuss management from diagnosis to treatment based on illustrative cases from daily practice.

Unusual Case of Nephrotic Syndrome From Light Chain Amyloidosis in a 37-Year-Old Patient

Amyloidosis with renal involvement is a well-known cause of nephrotic syndrome. Immunoglobulin light-chain amyloidosis (AL), which is a result of monoclonal light-chain deposition in the kidney from plasma cell dyscrasia, is rare before the age of 40 and typically occurs in old patients. Most cases of renal amyloidosis in young patients are secondary to chronic inflammatory disease. We are reporting a case of a 37-year-old male who was transferred to our hospital for evaluation of possibly acquired bleeding disorder. He was initially presented to an outside hospital with bleeding per rectum for three days duration and one-week history of abdominal pain and bloating. He was found to have nephrotic range proteinuria with hypoalbuminemia and hyperlipidemia. A kidney biopsy was performed to identify the cause of his nephrotic syndrome, and a biopsy showed AL amyloidosis. Bone marrow biopsy performed showed plasma cell myeloma, and the patient was started on induction chemotherapy. Even though the incidence of AL amyloidosis is low before age of 40, we should always perform monoclonal gammopathy workup in patients with nephrotic syndrome regardless of the age. Prompt bone marrow biopsy should be performed to confirm the diagnosis, and starting the treatment as one of the factors that affect the prognosis of AL amyloidosis is early diagnosis.

Acquired von Willebrand Syndrome

Acquired von Willebrand syndrome can occur in the setting of myeloproliferative neoplasms; plasma cell dyscrasias and other lymphoproliferative disorders; autoimmune conditions; and causes of increased shear forces, such as aortic stenosis or other structural heart disease and mechanical circulatory support. The depletion of von Willebrand factor, especially high-molecular-weight multimers, can lead to mucocutaneous bleeding and the formation of arteriovenous malformations, particularly in the gastrointestinal tract. Management focuses on correction of the underlying cause when possible, but may include intravenous immunoglobulins, von Willebrand factor concentrate, rituximab, or antiangiogenic therapy depending on the clinical context.

Challenges in the management of patients with systemic light chain (AL) amyloidosis during the COVID-19 pandemic

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated coronavirus disease 2019 (COVID-19) is primarily manifested as a respiratory tract infection, but may affect and cause complications in multiple organ systems (cardiovascular, gastrointestinal, kidneys, haematopoietic and immune systems), while no proven specific therapy exists. The challenges associated with COVID-19 are even greater for patients with light chain (AL) amyloidosis, a rare multisystemic disease affecting the heart, kidneys, liver, gastrointestinal and nervous system. Patients with AL amyloidosis may need to receive chemotherapy, which probably increases infection risk. Management of COVID-19 may be particularly challenging in patients with AL amyloidosis, who often present with cardiac dysfunction, nephrotic syndrome, neuropathy, low blood pressure and gastrointestinal symptoms. In addition, patients with AL amyloidosis may be more susceptible to toxicities of drugs used to manage COVID-19. Access to health care may be difficult or limited, diagnosis of AL amyloidosis may be delayed with detrimental consequences and treatment administration may need modification. Both patients and treating physicians need to adapt in a new reality.

Coagulation and fibrinolytic features in AL amyloidosis with abnormal bleeding and usefulness of tranexamic acid

Abnormal bleeding is sometimes observed in patients with immunoglobulin light chain (AL) amyloidosis. Although several theories have been proposed regarding the pathological causes of the bleeding tendency in AL amyloidosis, many lacked sufficient evidence and full consensus. We conducted a retrospective survey at a single institution to assess bleeding manifestations, methods for evaluating hematological abnormalities, and treatments for bleeding in patients with systemic AL amyloidosis over the past 13 years. The participants were 10 men and 14 women, aged 39-84 years (mean 65 years). The prevalence of bleeding was 29%. Prolonged prothrombin time (PT), elevated plasmin-α2-antiplasmin complex, and factor X deficiency were distinctive to the bleeding group. Two case studies showed that tranexamic acid was effective for treating this hematological condition. However, two patients with normal PT and activated partial thromboplastin time (APTT) also had a bleeding manifestation. The rates of administration of coagulation and fibrinolytic tests were relatively low in the non-bleeding group. Therefore, a close investigation concerning coagulation and fibrinolysis should be performed in every patient with AL amyloidosis regardless of the PT/APTT values. A more careful, comprehensive, and large-scale study is required to reinforce these findings.

Disease progression and defects in primary hemostasis as major cause of bleeding in multiple myeloma

BACKGROUND AND OBJECTIVES

In patients with multiple myeloma (MM), unexpected bleeding complications remain a major issue. Since routine coagulation parameters are often inconspicuous, diagnosis and treatment of the underlying coagulation disorders are challenging.

PATIENTS AND METHODS

In our single-center observational study, we analyzed 164 patients with MM for coagulation disorders and bleeding complications.

RESULTS

Prolonged closure times (CTs), measured by PFA-100, were the most common, abnormal coagulation test, found in 66% of bleeding patients vs 5% in non-bleeding, followed by qualitative defects of von Willebrand factor (VWF:CB/VWF:Ag ratios), found in 34% vs 1% in the non-bleeding group. Increased serum free light chains (SFLC) and SFLC ratios were significantly associated with prolonged CTs and acquired von Willebrand syndrome (AVWS). Prolonged CTs and AVWS were associated with disease progression, determined by dynamics of SFLC ratios (P < .001), serum creatinine level (P = .013), Beta-2 microglobulin (P = .03), LDH (P = .016), and bone marrow infiltration (P < .001). Of note, response to myeloma therapy was frequently correlated with normalization of coagulation parameters.

CONCLUSIONS

Bleeding complications in MM are predominantly caused by defects in primary hemostasis and associated with disease progression. In a peri-interventional workup, determination of CTs and VWF:CB/VWF:Ag ratios are of significant importance to assess bleeding risk.

Prevalence and prognostic value of D-dimer elevation in patients with AL amyloidosis

Light chain (AL) amyloidosis is a protein folding disorder that can affect many different organ systems, in addition to the coagulation pathway. D-dimer, a measurement of fibrin degradation, is commonly elevated in hematologic malignancies, but the prevalence and significance of D-dimer elevation in AL amyloidosis is unknown. We conducted an analysis of 921 patients with AL amyloidosis that presented to the Boston University Amyloidosis Center. Baseline characteristics and laboratory data of the 897 patients included in the final cohort were analyzed. Four hundred twenty three patients (47%) had an elevated D-dimer (>0.5 μg/mL). Multivariate analysis demonstrated that a normal D-dimer level of ≤0.5 μg/mL, and a level of >0.5 μg/mL but <1 μg/mL, conferred a lower risk of mortality (HR 0.49 and 0.59, respectively) when compared to a D-dimer level ≥ 1 μg/mL. The increased risk of mortality in patients with a D-dimer level ≥ 1 μg/mL was present in all cardiac stages. The median overall survival based on D-dimer range of ≤0.5, >0.5 but <1, and ≥ 1 μg/mL was 5.86, 4.04, and 2.08 years, respectively (P < .001). This retrospective analysis demonstrates the high prevalence of D-dimer elevation in AL amyloidosis and confirms that this laboratory finding is independently associated with decreased survival.

Portal Hypertension and a Stiff Liver

Portal hypertension (PH) is a common clinical syndrome leading to severe complications. In the western world, about 90% of cases of PH are due to liver cirrhosis, and thanks to the availability of ultrasound elastography methods, this diagnosis is usually confirmed at bedside. We report a case of a patient presenting with PH and ascites initially suspected of suffering from liver cirrhosis. The finding of large hepatomegaly and a massive increase in liver stiffness prompted us to perform a liver biopsy. This revealed no fibrosis, but diffuse primary amyloidosis (AL amyloidosis). We discuss the diagnostic and treatment of this case, with emphasis on non-invasive imaging methods available for diagnosis and follow up.

Acquired von Willebrand Syndrome Associated to Secondary IgM MGUS Emerging after Autologous Stem Cell Transplantation for AL Amyloidosis

Acquired von Willebrand syndrome (AVWS) is a rare hemorrhagic disorder that occurs in patients with no prior personal or family history of bleeding. Here, we describe a case of AVWS occurring after autologous stem cell transplantation (ASCT). Interestingly, AVWS developed after bortezomib-based induction and conditioning regimens. Recent evidence suggests that the proximity of the bortezomib therapy to the collection of stem cells with consequent depletion of regulatory T cells after the conditioning regimen could explain some of the unusual autoimmune complications reported in patients receiving bortezomib prior to ASCT. In addition, this patient developed a secondary MGUS post-ASCT, which may have also contributed to the AVWS. To the best of our knowledge, this is the first case of post-ASCT AVWS reported. Prospective data is needed to better elucidate the mechanisms by which these unusual complications occur in patients receiving bortezomib prior to ASCT.

Amyloidosis of the liver on shear wave elastography: case report and review of literature

Amyloidosis is extremely rare, with an estimated 2225 new US cases reported annually. Signs and symptoms of the disease are subtle and imaging findings are not pathognomonic. Currently, diagnosis requires biopsy to demonstrate the deposition of amyloid. Elastography is a new imaging modality that evaluates tissue elasticity. It has shown to have efficacy in characterizing thyroid nodules, detecting prostate cancer, and staging liver fibrosis. We present a case of hepatic amyloidosis in a 51-year-old male that demonstrates significantly increased stiffness with a median value of 99.1 kPa (range 25.7-188.9 kPa) on shear-wave elastography (SWE) imaging, which is significantly higher than the cut-off range reported for cirrhosis on SWE (10.4-11.5 kPa). This finding raises the possibility that elastographic imaging may be sensitive to tissue mechanical changes induced by amyloid deposition.

Distinct mechanisms account for acquired von Willebrand syndrome in plasma cell dyscrasias

Acquired von Willebrand syndrome (AVWS) is a rare bleeding disorder that may cause life-threatening hemorrhages in patients with plasma cell dyscrasias (PCDs). Early diagnosis and treatment require a thorough understanding of its underlying pathophysiology. Two patients with IgG MGUS presented with dramatically decreased plasma von Willebrand factor (VWF) and a severe type-1 pattern on multimer analysis. A prompt response to intravenous immunoglobulins (IVIG), but not to VWF/FVIII, was consistent with accelerated immunologic clearance of plasma VWF. Another IgG MGUS patient showed a type-2 pattern and a less pronounced response to IVIG, suggesting that additional mechanism(s) contributed to AVWS evolution. In a patient with Waldenström's macroglobulinemia and severe depletion of plasma VWF, multimer analysis indicated association of the IgM paraprotein with VWF before, but not after plasmapheresis, resulting in destruction of the agarose gel and a characteristically distorted band structure of VWF multimers. A type-2 pattern with highly abnormal VWF triplets and laboratory evidence of excessive fibrinolytic activity suggested that plasmin-mediated VWF degradation contributed to AVWS in a patient with multiple myeloma (MM) and AL amyloidosis. Finally, in a patient with IgG MM, maximally prolonged PFA-100® closure times and a specific defect in ristocetin-induced platelet agglutination, both of which resolved after remission induction, indicated interference of the paraprotein with VWF binding to platelet GPIb. Importantly, in none of the six patients, circulating autoantibodies to VWF were detected by a specific in-house ELISA. In summary, when evaluating PCD patients with severe bleeding symptoms, AVWS due to various pathogenic mechanisms should be considered.

Risk factors for venous thromboembolism in immunoglobulin light chain amyloidosis

Patients with immunoglobulin light chain amyloidosis are at risk for both thrombotic and bleeding complications. While the hemostatic defects have been extensively studied, less is known about thrombotic complications in this disease. This retrospective study examined the frequency of venous thromboembolism in 929 patients with immunoglobulin light chain amyloidosis presenting to a single referral center, correlated risk of venous thromboembolism with clinical and laboratory factors, and examined complications of anticoagulation in this population. Sixty-five patients (7%) were documented as having at least one venous thromboembolic event. Eighty percent of these patients had events within one year prior to or following diagnosis. Lower serum albumin was associated with increased risk of VTE, with a hazard ratio of 4.30 (CI 1.60-11.55; P=0.0038) for serum albumin less than 3 g/dL compared to serum albumin greater than 4 g/dL. Severe bleeding complications were observed in 5 out of 57 patients with venous thromboembolism undergoing treatment with anticoagulation. Prospective investigation should be undertaken to better risk stratify these patients and to determine the optimal strategies for prophylaxis against and management of venous thromboembolism.

[Spontaneous intrahepatic hematoma: an unexpected etiology]

INTRODUCTION

Diagnosis of AL amyloidosis can be complicated by the diversity and the absence of specificity of symptoms.

CASE REPORT

We report a patient who presented with a non-traumatic hepatic hematoma, leading to the discovery of hepatic amyloidosis secondary to probable multiple myeloma. The originality of our report lies in the discovery of two acquired abnormalities of haemostasis: a factor X deficiency and an acquired von Willebrand syndrome, by a likely inhibitor.

CONCLUSION

Our case report is a reminder of the importance of haemostasis analysis in AL amyloidosis.

Multiple arterial and venous thromboembolic complications in AL amyloidosis and cardiac involvement: a case report and literature review

A 41-year-old woman with immunoglobulin light chain (AL) systemic amyloidosis with cardiac and gastrointestinal involvement developed multiple arterial and venous thromboembolic complications. Treatment with unfractionated heparin was complicated by life-threatening gastrointestinal bleeding. Work up for hereditary thrombophilia was unrevealing. Treatment with cyclophosphamide, bortezomib and dexamethasone combination regimen led to hematologic response without further thromboembolic complications. While thromboembolic complications have been reported in AL amyloidosis and cardiac involvement, this unique case highlights the complexity of the disease, the various pathogenic mechanisms at play and the difficult management decisions necessary in caring for these complex patients. A literature review of thrombembolic complications in patients with amyloidosis is presented.

Differential diagnosis of localized and systemic amyloidosis based on coagulation and fibrinolysis parameters

BACKGROUND

A simple assay that can discriminate between localized and systemic amyloidosis is needed.

METHODS

Coagulation and fibrinolysis parameters were measured in subjects with active or progressive systemic amyloidosis (Group A; 9 patients), systemic amyloidosis in complete remission (Group B; 6 patients), localized AL amyloidosis (Group C; 6 patients), monoclonal gammopathy of undetermined significance (Group D; 5 patients), chronic glomerulonephritis with proteinuria (Group E; 22 patients), or glomerulonephritis in complete remission (Group F; 11 patients).

RESULTS

No significant differences were noted between Group A and the other groups in the international normalized ratio of prothrombin time, activated partial thromboplastin time, and levels of antithrombin and plasminogen. Levels of thrombin-antithrombin (TAT) complexes, fibrinogen, fibrinogen degradation product d-dimers, and plasmin-α2-plasmin inhibitor complexes (PIC) were significantly elevated in Group A. All patients that showed TAT complexes, fibrinogen, and PIC levels greater than 4.2 ng/mL, 399 mg/dL, and 1.4 μg/mL, respectively, had active or progressive systemic amyloidosis. All patients with TAT complex levels less than 3.6 ng/mL, fibrinogen levels less than 355 mg/dL, and PIC levels less than 0.9 μg/mL had localized AL amyloidosis.

CONCLUSION

Analyses of TAT complexes, fibrinogen, and PIC can be used to differentiate localized AL amyloidosis from systemic amyloidosis.

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.

Non-invasive detection of hepatic amyloidosis: FibroScan, a new tool

INTRODUCTION

FibroScan, a non-invasive tool for measuring liver stiffness (LS), is not specific to liver fibrosis. Other extra-hepatic conditions may modify the LS value.

OBJECTIVES

Our aim was to examine whether amyloid deposition in the liver may modify LS.

METHODS

LS was measured prospectively in 41 patients with systemic AL amyloidosis (AL) in the French AL Reference Center, comprising: 5 patients with liver involvement (LI) and no cardiac involvement (CI), 11 with CI and no LI, 12 with both LI and CI and 13 with neither (2005 consensus criteria); 26 negative controls, 50 patients infected with Hepatitis C virus (HCV)-infected and 18 AL-free patients with right-sided heart disease ('cardiac controls') were also examined.

RESULTS

Median LS was significantly higher in patients with AL with liver involvement [27.4 (10.3-75) kPa] than in negative controls [4.8 (2.8-11.9) kPa] (p < 0.0001), and patients infected with HCV [(6.8 (2.9-69.1) kPa] (p = 0.001), and tended to be higher than in the 'cardiac controls' [11 (4.1-75) kPa] (p = 0.08). A cut-off value of 17.3 kPa, prioritising specificity, is proposed for routine diagnosis of significant AL liver infiltration.

CONCLUSION

LS > 17.3 kPa is suggestive of AL hepatic disease in patients with non-fibrotic liver changes, and may have diagnostic value in patients with known AL.

[Hereditary and non-hereditary cutaneous amyloidoses]

Amyloid and amyloidosis describes a heterogeneous group of diseases which are characterized by the pathological extracellular deposition of autologous proteins. Basically, amyloidoses can be divided into systemic or organ-limited (e.g. cutaneous) forms and can be acquired or hereditary in nature. The subclassification discriminates between primary amyloidosis (in the absence of an obvious predisposing disease) and secondary amyloidosis (if caused by a certain underlying disease). The subclassification of amyloidoses is based on the main protein constituent and therefore on the chemical composition of the amyloid fibrils. However, the exact etiopathogenesis of amyloid formation remains unclear. In addition to the clinical presentation, histology, electron microscopy and biochemical-immunological differentiation are also decisive for a proper diagnosis. In cutaneous amyloidosis the deposition of amyloid either occurs along reticulin fibers and the basal membrane (perireticulary amyloidoses) or along collagen fibers (pericollagenous amyloidosis). The purpose of this article is to provide an up-to-date overview on the different kinds of cutaneous amyloidoses.

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.