Hemostatic abnormalities associated with monoclonal gammopathies

Newly diagnosed multiple myeloma with bleeding and coagulation abnormalities caused by a thrombin-inhibiting substance

Approximately 7% of patients with newly diagnosed multiple myeloma (MM) experience bleeding complications with varying causes, but few reports have described these complications. Here we report the case of a patient with newly diagnosed MM who presented with a bleeding tendency and various coagulation abnormalities. Chromogenic assays, thrombin time, and reptilase time revealed the presence of a thrombin-inhibiting substance that inhibited release of fibrinopeptide A from fibrinogen. The coagulation abnormalities improved after treatment with daratumumab, lenalidomide, and dexamethasone. As the thrombin inhibition mechanism remains unclear, no previous studies have reported recent treatment outcomes in older patients producing thrombin-inhibiting substances, which can hinder clinical treatment. Therefore, we believe that the diagnosis and the treatment course of this case provide valuable information. Moreover, such case reports provide significant insights into the pathophysiology of bleeding complications associated with MM.

Acquired Bernard-Soulier syndrome and hypodysfibrinogenaemia because of multiple myeloma

We describe a case of a patient with multiple myeloma with initial presentation simulating a bleeding disorder. Detailed coagulation work-up showed hypodysfibrinogenaemia along with a platelet function defect consistent with acquired Bernard-Soulier syndrome (BSS). Multiple plasma exchanges led to significant improvement in his bleeding symptoms. To the best of our knowledge, this is the first described case of simultaneous presentation of hypodysfibrinogenaemia and BSS secondary to multiple myeloma.

Anticoagulation in Patients with Platelet Disorders

Platelet disorders comprise heterogeneous diseases featured by reduced platelet counts and/or impaired platelet function causing variable bleeding symptoms. Despite their bleeding diathesis, patients with platelet disorders can develop transient or permanent prothrombotic conditions that necessitate prophylactic or therapeutic anticoagulation. Anticoagulation in patients with platelet disorders is a matter of concern because the bleeding risk could add to the hemorrhagic risk related to the platelet defect. This review provides an overview on the evidence on anticoagulation in patients with acquired and inherited thrombocytopenia and/or platelet dysfunction. We summarize tools to evaluate and balance bleeding- and thrombotic risks and describe a practical approach on how to manage these patients if they have an indication for prophylactic or therapeutic anticoagulation.

Management of intraoral bleeding in patients with Waldenström macroglobulinemia: A protocol proposal

AIM

Waldenström macroglobulinemia is a type of non-Hodgkin lymphoma with poor prognosis observed in patients with hyperviscosity syndrome because of its tendency for fatal symptoms. This study investigated the risk of intraoral bleeding in patients with Waldenström macroglobulinemia based on hyperviscosity syndrome stage and oral health status, and described potential strategies for managing intraoral bleeding.

METHODS AND RESULTS

Between April 2012 and March 2017, seven patients with Waldenström macroglobulinemia underwent dental procedures or tooth extraction. Patient records were retrospectively reviewed to obtain data of symptoms, clinical and radiographic findings, treatment details, pretreatment hematological findings, hyperviscosity syndrome status, perioperative method for local haemostasis, postoperative bleeding, and prognosis. The mean patient age was 71.2 years, and the male-to-female ratio was 6:1. Treatment modalities for oral management comprised tooth extraction, scaling, and oral cavity cleaning. Three patients were admitted for hyperviscosity syndrome; one of the patients exhibited postoperative bleeding because of poor oral hygiene, whereas the two other patients with good oral hygiene did not experience intraoral bleeding regardless of the presence of hyperviscosity syndrome.

CONCLUSION

We recommended that the risk of oral bleeding in patients with Waldenstrom's macroglobulinemia should be assessed for oral health in addition to the stage of hyperviscosity syndrome.

Interference of M-protein on prothrombin time test - case report

The aim of this report was to present a case of interference on prothrombin time (PT) test that directed further laboratory diagnostics and resulted with final detection of monoclonal gammopathy in an 88-year old man. Routine coagulation testing during medical examination at Emergency Department revealed unmeasurable PT (< 7% activity) and activated partial thromboplastin time (aPTT) within reference range. After repeated sampling for coagulation testing, PT was unmeasurable again, as well as fibrinogen level (< 0.8 g/L), thrombin time (TT) was significantly prolonged (107 seconds) and aPTT was within reference range. In both plasma samples refrigerated at 4 ˚C overnight, white gelatinous precipitate was visible between the cell and plasma layers and the presence of monoclonal protein (M-protein) was suggested in our patient. Further laboratory diagnostics revealed total serum proteins at concentration of 123 g/L and the presence of M-protein IgG lambda (λ) at concentration of 47.1 g/L. These results suggested monoclonal gammopathy as an underlying pathophysiological condition in our patient. Activities of coagulation factors II, V, VII and X were within reference ranges or increased. These results and correction of unmeasurable PT result to 67% in mixing test with commercial normal plasma suggest in vitro rather than in vivo interference of M-protein on PT result. In contrast, significantly prolonged TT results in all analysed samples suggest impact of M-protein on this global coagulation test due to possible effect on fibrin polymerization.

The effect of paraprotein on platelet aggregation

BACKGROUND

Some patients with paraproteinemia have platelet aggregation disorders and the aim of this study was to examine disturbance of platelet aggregation in healthy blood donors by isolated paraprotein in vitro.

METHODS

Using Rivanol, paraprotein was separated from the serum of ten patients with paraproteinemia, who had decreased platelet aggregation with several inducers. Platelet aggregation in ten healthy donors was measured with and without addition of the isolated induced paraprotein. The test was repeated with added human immunoglobulins for intravenous use.

RESULTS

Average of maximal levels of platelet aggregation has been significantly decreased in plasma rich in platelets (PRP) of healthy donors after addition of paraprotein when inducers are used: adenosine diphosphate (ADP) (P = 0.007), collagen (COL) (P = 0.008), ristocetin (RIS) (P = 0.001), and epinephrine (EPI) (P = 0.002). Average of latent time of platelet aggregation was significantly prolonged in healthy donors after addition of paraprotein with inducers: COL (P = 0.008), RIS (P = 0.008) and EPI (P = 0.006) while addition of human immunoglobulins caused no change in platelet aggregation. In comparison, when human immunoglobulins were added, maximal platelet aggregation and latent time did not change significantly. Paraprotein isolated from patients with paraproteinamia, who had decrease platelet aggregation, had significantly decreased platelet aggregation when added to PRP of healthy donors, in vitro.

CONCLUSION

Platelet aggregation was not significantly changed was confirmed with addition of human immunoglobulins.

Artifactual laboratory abnormalities in patients with paraproteinemia

Paraproteinemia, most often as a result of monoclonal gammopathy of unknown significance (MGUS), is very common and its prevalence is expected to increase with the aging of the population. Paraproteins can be associated with a variety of laboratory abnormalities. These may occur as a result of the underlying disease process that causes paraproteinemia, or may result from the paraproteins affecting a physiologic function in vivo. Laboratory abnormalities may also occur artifactually as a result of interference by the paraproteins with a laboratory test in vitro. A wide variety of laboratory tests may be affected, including several commonly obtained tests such as blood counts, serum sodium, calcium, phosphorous, and high-density lipoprotein (HDL) cholesterol. There is poor correlation between the concentration or type of paraproteins and the likelihood of interference. Awareness of this possibility is important so as to avoid erroneous diagnostic conclusions or unnecessary testing.

Gastrointestinal plasmacytoma presenting as gastrointestinal bleeding

Clinical manifestations of gastrointestinal (GI) involvement in multiple myeloma (MM) are uncommon. We report a case of plasmacytoma presenting as upper GI bleeding in a patient with a known diagnosis of MM. Gastrointestinal bleeding persists despite aggressive medical and endoscopic treatment. The aim of our report is to heighten the awareness of plasmacytoma as an etiology of GI bleeding in patients with MM. Abnormal hemostasis, specifically the imbalance in function of all major components of the coagulation cascade, increasing bleeding risk in patients with MM, is also discussed.

Acquired platelet dysfunction

Acquired platelet dysfunction is encountered frequently in clinical practice. The usual clinical presentation is that of mucosal bleeding, epistaxis, or superficial epidermal bleeds. Often, the dysfunctional platelets are related to a medication or a systemic disorder. Normally, when platelets are exposed to damaged endothelium, they adhere to the exposed basement membrane collagen and change their shape from smooth disks to spheres with pseudopodia. Then, they secrete the contents of their granules, a process referred to as the release reaction. Additional platelets form aggregates on those platelets that have adhered to the vessel wall. As a result, the primary hemostatic plug is formed, and bleeding is arrested. This article reviews the various forms of acquired platelet dysfunction that result in decreased platelet aggregation, adhesion, or secretion.

Multiple myeloma and hypercoagulability leading to internal jugular vein thrombosis in a dialysis patient

A 68-year-old male patient with end-stage renal failure on maintenance hemodialysis using a right internal jugular dual-lumen catheter developed thrombosis of the internal jugular vein with extension into the superior vena cava after removal of the catheter. As he developed a lower backache with MRI finding of disease of the D11 and D12 vertebrae, a bone biopsy performed showed multiple myeloma. Anticoagulant therapy led to recanalization of the thrombosed veins.

Disturbances of anticoagulation and fibrinolytic systems in monoclonal gammopathies-another mechanism of M-protein interference with hemostasis

Monoclonal gammopathies (MG) may be associated with unique monoclonal immunoglobulin (MIg)-induced disturbances of either primary hemostasis or plasma coagulation. We have investigated the possible interference of MIg with antithrombotic systems in 49 patients with MG. Although an increase of tissue-type plasminogen activator (t-PA) activity was the most frequent abnormality in our group, defect of anticoagulation factors was found in 26.5% of patients. The relationship between MIg type and concentration and frequency of antithrombotic factor abnormalities was not found. The risk of venous thrombosis was higher in patients with the defect in comparison with the unaffected group (46% vs. 22%), but the difference was not statistically significant. Bleeding complications were markedly less frequent in the group of patients with defect of anticoagulation mechanisms (0% vs. 17%). In conclusion, we have found abnormalities in anticoagulation and/or fibrinolytic system, analogous to well-known disturbances of hemostatic mechanisms, in more than a quarter of patients with MG. The interference of M-protein with antithrombotic pathways is supposed to be another mechanism of secondary deficiencies of antithrombin III (AT III), protein C (PC), protein S (PS), plasminogen and APC resistance. Together with other factors, it could contribute to higher risk of thromboembolism in myeloma patients.

A non-immunological phospholipid-dependent coagulation inhibitor associated with IgGlambda-type multiple myeloma

We investigated the rare case of a patient with IgGlambda multiple myeloma for whom both prothrombin time and APTT were significantly prolonged. The IgG inhibited coagulation reactions upstream from prothrombin when coagulation was initiated by mRVVT, but not by FXa, as indicated by a chromogenic substrate for FXa. The mPT and the mAPTT showed inhibition of FXa generation in both the intrinsic and extrinsic pathways. The IgG inhibited both protein C (indicated by APTT) and FX (indicated by RVV) but not amidolysis for either activated protein C or FXa. The addition of excess phospholipid significantly shortened the prolonged RVVT of the patient. It inhibited the coagulation reactions of normal plasma and was dependent on decreasing the PS concentration in the APTT reagent. It was suggested that the IgG showed lupus anticoagulant (LA)-like activity that inhibited phospholipid-dependent coagulation reactions in the intrinsic, extrinsic, and common pathways. However, the IgG did not bind cardiolipin-beta2GPI complex, beta2GPI, or prothrombin in ELISA assays. The IgG did not bind to either PS or phospholipid complexes in the presence or absence of prothrombin, FX, or FXa. Interestingly, the IgG lost its LA like-activity when it was degraded to F(ab')2 and Fc fragments by pepsin. We suspected that the IgG might inhibit the interaction between coagulation factors and acid phospholipid non-immunologically and that this process requires an intact IgG conformation, although the reaction mode is still not clear.

Rare acquired bleeding disorders

Accurate diagnosis of the cause of bleeding is a prerequisite for determination of the optimal therapeutic response. Clinicians are generally aware of the more prevalent hemorrhagic syndromes but some rare acquired conditions are also of importance. In many of these, inhibitors of coagulation factors or of platelet adhesion/aggregation cause bleeding. These inhibitors are generally, but not always, immunoglobulins. In this review, the less common inhibitors of coagulation and hemostasis, as well as some important but rare nutritional, iatrogenic and disease associated hemorrhagic disorders, are described.

Lupus anticoagulant-like activity observed in a dimeric lambda protein produced by myeloma cells

We report here a lupus anticoagulant (LA)-like activity observed in a 45-year-old man with Bence-Jones protein (BJP) lambda-type multiple myeloma. This patient showed no clinical symptoms of thrombosis or bleeding diathesis. Laboratory examination on admission showed mild anemia, prolongation of activated partial thromboplastin time (APTT) (APTT, 56.2 seconds; control, 29.1 seconds), normal prothrombin time, normal thrombin time, and massive proteinuria (2.3 g/d). The mix test with normal plasma showed the presence of circulating anticoagulant. Based on the assumption that the lambda-type BJP may have been responsible for the prolongation of APTT, we purified the BJP from the patient's urine using column works. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting showed that the purified protein was a 48-kd homodimer of immunoglobulin lambda-chains. Addition of the purified dimeric lambda-type BJP to the normal plasma prolonged both APTT and dilute Russell's viper venom time (DRVVT) in a dose-dependent manner, and the negatively charged phospholipid-dependent prothrombinase activity was significantly inhibited in the presence of this protein. Furthermore, both the prolongation of DRVVT and the inhibition of the prothrombinase activity were almost completely abrogated under the condition of high ionic strength. These findings collectively suggest that the dimeric lambda-type BJP showed LA-like activity via the mechanism of ionic charge.