Hemorheological parameters in Monoclonal Gammopathy of Undetermined Significance (MGUS)

Analysis of fibrin networks using topological data analysis - a feasibility study

Blood clot formation, a crucial process in hemostasis and thrombosis, has garnered substantial attention for its implications in various medical conditions. Microscopic examination of blood clots provides vital insights into their composition and structure, aiding in the understanding of clot pathophysiology and the development of targeted therapeutic strategies. This study explores the use of topological data analysis (TDA) to assess plasma clot characteristics microscopically, focusing on the identification of the elements components, holes and Wasserstein distances. This approach should enable researchers to objectively classify fibrin networks based on their topologic architecture. We tested this mathematical characterization approach on plasma clots formed in static conditions from porcine and human citrated plasma samples, where the effect of dilution and direct thrombin inhibition was explored. Confocal microscopy images showing fluorescence labeled fibrin networks were analyzed. Both treatments resulted in visual differences in plasma clot architecture, which could be quantified using TDA. Significant differences between baseline and diluted samples, as well as blood anticoagulated with argatroban, were detected mathematically. Therefore, TDA could be indicative of clots with compromised stability, providing a valuable tool for thrombosis risk assessment. In conclusion, microscopic examination of plasma clots, coupled with Topological Data Analysis, offers a promising avenue for comprehensive characterization of clot microstructure. This method could contribute to a deeper understanding of clot pathophysiology and thereby refine our ability to assess clot characteristics.

Rheological properties of blood in multiple myeloma patients

Multiple myeloma (MM) is considered to be one of the hematological malignancies formed by excessive and abnormal proliferation of plasmocytes. Among other parameters, several blood tests are used to diagnose multiple myeloma. The hemorheological profile in multiple myeloma is not widely studied. Hemorheology includes the study of measuring the deformability and aggregation of erythrocytes, blood viscosity, and sedimentation rate. The degree of deformability of blood cells is necessary to maintain proper vital functions. Proper deformability of red blood cells ensures proper blood circulation, tissue oxidation and carbon dioxide uptake. The aim of the study was to compare morphology and blood rheology parameters in patients with MM and healthy individuals. The study included 33 patients with MM, and 33 healthy subjects of the same age. The hematological blood parameters were evaluated using ABX MICROS 60 hematology analyzer. The LORCA Analyzer to study erythrocyte aggregation and deformability. Patients with MM had lower red blood cells count (RBC) (9.11%) (p < 0.001) and half time of total aggregation (T1/2) (94.29%) (p < 0.001) values and higher mean corpuscular volume (MCV) (5.50%) (p < 0.001), aggregation index (AI) (68.60%) (p < 0.001), total extent of aggregation (AMP) (87.92%) (p < 0.001) values than the healthy control group. Aggregation in patients with MM is different compared to healthy individuals. It was observed that the percentage of cell aggregation is almost 50% higher than in the control group. The study of morphology, aggregation and deformability of erythrocytes in patients with suspected MM may be helpful in making clinical decisions.

Evaluation of Retinal Blood Flow in Patients with Monoclonal Gammopathy Using OCT Angiography

BACKGROUND

Monoclonal gammopathy (MG) is characterized by monoclonal protein overproduction, potentially leading to the development of hyperviscosity syndrome.

OBJECTIVE

To assess retinal circulation using optical coherence tomography angiography (OCTA) parameters in patients with monoclonal gammopathy.

METHODS

OCTA measurements were performed using the Optovue AngioVue system by examining 44 eyes of 27 patients with MG and 62 eyes of 36 control subjects. Superficial and deep retinal capillary vessel density (VD SVP and DVP) in the whole 3 × 3 mm macular and parafoveal area, foveal avascular zone (FAZ) area, and central retinal thickness (CRT) were measured using the AngioAnalytics software. The OCTA parameters were evaluated in both groups using a multivariate regression model, after controlling for the effect of imaging quality (SQ).

RESULTS

There was no significant difference in age between the subjects with monoclonal gammopathy and the controls (63.59 ± 9.33 vs. 58.01 ± 11.46 years; p > 0.05). Taking into account the effect of image quality, the VD SVP was significantly lower in the MG group compared to the control group (44.54 ± 3.22% vs. 46.62 ± 2.84%; p < 0.05). No significant differences were found between the two groups regarding the other OCTA parameters (p > 0.05).

CONCLUSIONS

A decreased superficial retinal capillary vessel density measured using OCTA in patients with MG suggests a slow blood flow, reduced capillary circulation, and consequent tissue hypoperfusion. An evaluation of retinal circulation using OCTA in cases of monoclonal gammopathy may be a sensitive method for the non-invasive detection and follow-up of early microcirculatory dysfunction caused by increased viscosity.

Erythrocyte deformability profile evaluated by laser diffractometry in patients with multiple myeloma: Re-examination of our cases

BACKGROUND

Multiple myeloma is a complex pathology which represents about 10 % of all hematological neoplasms. It can often present changes in the hemorheological profile and, in relation to this last topic, our aim is to evaluate the hemorheological profile in a group of multiple myeloma patients, with reference to erythrocyte deformability.

METHODS

We have examined the profile of the erythrocyte deformability in multiple myeloma enrolling 29 patients; this profile, expressed as elongation index at several shear stress, has been obtained using the diffractometric method.

RESULTS

By comparing normal controls and MM patients, a significant decrease in erythrocyte deformability, especially at low shear stresses, but we did not observe any significant differences about this profile subdividing the whole group of MM patients according to the degree of bone marrow plasma cell infiltration, to the red blood cell distribution width and to the serum values of LDH.

CONCLUSIONS

In this paper we have taken in consideration all the hypothesis for a possible explanation of the behaviour of this a reduced erythrocyte deformability in multiple myeloma. Erythrocyte deformability interferes with the physiological release of oxygen to tissues, with several clinical implications.

The unpredictable erythrocyte deformability alteration in some hematological disorders: How the classification of primary hyperviscosity syndromes could change

According to Wells classification, it is possible to distinguish the primary hyperviscosity syndromes in polycythemic, sclerocythemic and sieric and/or plasmatic. In polycythemia vera, multiple myeloma, Waldenström's macroglobulinemia, and monoclonal gammopathy of undetermined significance, we have observed an unexpected behaviour of the erythrocyte deformability. This data highlights that the hemorheological alteration present in polycythemia vera has not been related to the increase of RBC mass only, as well as that present in plasmacellular dyscrasias has not been attributable to the increase of plasma viscosity only.The aim of this paper is to suggest some starting points for an accurate reflection, emphasizing the need of a revision of the current classification of primary hyperviscosity syndromes.

Monoclonal Gammopathy of Thrombotic Significance

The current review provides an overview of the thrombotic risk observed in patients with MG who do not otherwise require treatment. We discuss clinical and biomarker studies that highlight the heterogenous hemostatic profile observed in these patients and how knowledge has evolved over the past 20 years. Biomarker studies suggest shared biologic features between multiple myeloma and monoclonal gammopathy of undetermined significance (MGUS), which involves both hypercoagulability and platelet activation. Hemostatic abnormalities identified in MGUS patients cannot be translated into clinical practice as they lack correlation to clinical events. The prothrombotic phenotype of MGUS patients has not been ascertained yet, but novel data on coagulation markers are promising. We also review rare conditions associated with the thrombogenic properties of the monoclonal protein that predispose to arterial, venous or microthrombotic events and demonstrate that the M-protein can be linked to clinically significant thrombotic events. Cryoglobulinemia, cryofibrinogenemia, cryo-crystaloglobulinemia and MG-related antiphospholipid syndrome are reviewed. We propose the new umbrella term "monoclonal gammopathy of thrombotic significance" (MGTS) to refer to significant, recurrent thrombotic events in patients with MGUS that provide a rationale for targeting the underlying plasma cell clone. Identifying MGUS patients at high risk for thrombotic events is currently a challenge.

High Output Heart Failure in Multiple Myeloma: Pathogenetic Considerations

Simple Summary

Multiple myeloma is a plasma cell disorder that accounts for around 10% of all haematological malignancies. This neoplasia is often associated with a significant prevalence of cardiovascular complications resulting from several factors, unrelated and/or related to the disease. Among cardiovascular complications, the high output heart failure is of great importance as it is related to a worse prognosis for patients. It is important to point out that, despite the availability of more and more numerous and effective drugs, myeloma remains an incurable disease, with frequent relapses and several treatment lines, with the need, therefore, for a careful evaluation of patients, especially from a cardiological point of view. For this reason, we are proposing a comprehensive overview of different pathogenetic mechanisms responsible for high output heart failure in multiple myeloma, including artero-venous shunts, enhanced angiogenesis, glutamminolysis, hyperammonemia and hemorheological alterations, with the belief that a multidisciplinary approach, in clinical evaluation is critical for the optimal management of the patient.

Abstract

The high output heart failure is a clinical condition in which the systemic congestion is associated to a high output state, and it can be observed in a non-negligible percentage of hematological diseases, particularly in multiple myeloma, a condition in which the risk of adverse cardiovascular events may increase, with a worse prognosis for patients. For this reason, though an accurate literature search, we provided in this review a complete overview of different pathogenetic mechanisms responsible for high output heart failure in multiple myeloma. Indeed, this clinical finding is present in the 8% of multiple myeloma patients, and it may be caused by artero-venous shunts, enhanced angiogenesis, glutamminolysis, hyperammonemia and hemorheological alterations with increase in plasma viscosity. The high output heart failure in multiple myeloma is associated with significant morbidity and mortality, emphasizing the need for a multidisciplinary approach.

A case of monoclonal gammopathy of undetermined significance and minimal change disease complicated by bilateral pulmonary emboli

Nephrotic syndrome and monoclonal gammopathy of undetermined significance are thought to be associated with venous thromboembolism. However, the association is thought to be weak and is often ignored by clinicians. We present a rare case of sudden-onset bilateral pulmonary emboli with lower extremity deep vein thrombosis in a patient diagnosed with both minimal change disease and immunoglobulin M (IgM) kappa monoclonal gammopathy of undetermined significance. No previous report has been published describing venous thromboembolism in a patient with plasma cell dyscrasia and minimal change disease. This case establishes the importance of considering a diagnostic workup for both disorders in patients with venous thromboembolism. Furthermore, venous thromboembolism risk in patients with both of these diseases is significant. Benefits of prophylactic anticoagulation in these patients are still controversial.

Comparison between whole blood viscosity measured and calculated in subjects with monoclonal gammopathy of undetermined significance and in patients with multiple myeloma: Re-evaluation of our survey

BACKGROUND

in this study, with a re-evaluation of the hemorheological determinants previously described in MGUS subjects and in MM patients, we have detected the calculated whole blood viscosity, according whether to the hematocrit and total plasma protein concentration (de Simone formula) or to the haematocrit and plasma fibrinogen level (Merrill formula), and a marker of the erythrocyte aggregation (albumin/fibrinogen level).

METHODS

data were expressed as means±standard deviation. Student's t test for unpaired data was used to compare MGUS subjects and MM patients. The correlation coefficient between mean erythrocyte aggregation (MEA) and hematocrit (Ht) was evaluated in MGUS, MM and MGUS + MM groups using the Spearman test.

RESULTS

the comparison between MGUS and MM shows that the measured blood viscosity and calculated blood viscosity based on hematocrit and total plasma protein, but not which estimated in relation to the hematocrit and plasma fibrinogen, differentiate the two groups. A difference between the two groups also regards the measured erythrocyte aggregation and its surrogate marker. In addition, the measured plasma viscosity at low shear rate (0.51 s-1) and, in particular, the ratio between plasma viscosity at low (0.51 s-1) and high (450 s-1) shear rates distinguish MGUS and MM.

CONCLUSIONS

calculated blood viscosity (de Simone formula and other formulas) and the surrogate marker of erythrocyte aggregation disclose an alike trend with the corresponding hemorheological determinants obtained by using their direct measurement.

Reflections on the unexpected laboratory finding of hemorheological alterations observed in some haematological disorders

Hyperviscosity syndrome is a clinical condition characterized by the slowing of blood flow through the vessels and it may be associated with several diseases. The nosographic classification of primary hyperviscosity conditions (Wells classification 1970) divided the primary hyperviscosity syndromes in polycythaemic, sclerocytemic and sieric. Recent and personal laboratory observations have highlighted an unexpected behaviour of the erythrocyte deformability observed in some haematological disorders such as polycythemia vera, multiple myeloma and monoclonal gammopathy of undetermined significance. The interest of this observation depends on the fact that up to now, according to the Wells classification, the hemorheological alteration present in PV was related to the increase of RBC mass while that present in MM and MGUS was attributable to the abnormality of plasma or serum viscosity only. Through an extensive research among the literature, using MEDLINE/PubMed to identify all published reports on the hyperviscosity syndromes, issues that until now have been dealt with separately will therefore be analyzed in a unique paper, allowing a global view. The aim of this paper is to provide some suggestions for reflection and emphasizing the need of a nosographic framework of hyperviscosity that, probably, deserves to be reviewed.

MGUS Predicts Worse Prognosis in Patients with Coronary Artery Disease

We performed a retrospective cohort study to analyze all 87 CAD patients with MGUS and 178 CAD patients without MGUS admitted in Zhongshan Hospital Fudan University from 2015 to 2017. Patients were followed up via regular patient visits or telephone, and the median follow-up period was 2.9 years. The end point of follow-up was the occurrence of major adverse cardiac events (MACE). CAD patients with MGUS had a higher risk of MACE than those without MGUS (log-rank P = 0.0015). After adjustment for other markers in the stepwise Cox regression model, MGUS was still related to the increasing risk of MACE incident (P = 0.002, HR = 2.308). Then, we constructed the nomogram based on the Cox regression model, and the concordance index (C-index) was 0.667. Hence, MGUS might be added into the risk model of CAD.

Cytomegalovirus infection with pulmonary embolism, splenic vein thrombosis and monoclonal gammopathy of undetermined significance: a case and systematic review

A 62-year-old immunocompetent woman was admitted with cytomegalovirus (CMV) infection, pulmonary embolism, splenic vein thrombosis and monoclonal gammopathy of undetermined significance (MGUS). Anticoagulation therapy was started. Two months later, seroconversion of CMV IgM to IgG was observed, while the monoclonal protein was no longer detectable. This suggests a relationship between acute CMV infection, transient MGUS and thrombosis. In accordance with current best practice guidelines for provoked venous thromboembolism (VTE), anticoagulation therapy could be discontinued after 3 months instead of 6 for unprovoked VTE, thereby reducing unnecessary time at risk of bleeding complications. While the relationships between CMV and both MGUS and thrombosis have been described independently, we are first to describe these three conditions occurring simultaneously.Furthermore, we provide a systematic review on the relation between CMV, MGUS and thrombosis.