[The evaluation of a patient with eosinophilia].

Eosinophilia is a common laboratory finding with a broad differential diagnosis. Eosinophilia can be classified as primary, secondary, or idiopathic hypereosinophilic syndrome (HES). Primary eosinophilia results from a clonal disorder of eosinophils, while secondary eosinophilia is reactive to a variety of underlying conditions, such as allergic diseases, infections, and drug reactions.

Plasmin-cleaved von Willebrand factor as a biomarker for microvascular thrombosis.

von Willebrand factor (VWF) is an essential contributor to microvascular thrombosis. Physiological cleavage by ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) limits its prothrombotic properties, explaining why ADAMTS13 deficiency leads to attacks of microthrombosis in patients with thrombotic thrombocytopenic purpura (TTP). We previously reported that plasminogen activation takes place during TTP attacks in these patients.

Open ADAMTS-13 conformation index predicts earlier relapse in immune-mediated thrombotic thrombocytopenic purpura.

Background: ADAMTS-13 adopts an open conformation in patients with immune-mediated thrombotic thrombocytopenic purpura (iTTP) in acute phase while being closed in healthy donors. We reported that a substantial number of patients with iTTP in remission with restored ADAMTS-13 activity (>50%) still had an open ADAMTS-13 conformation, although a closed conformation is expected given the extent of remission.

Objectives: To investigate whether open ADAMTS-13, represented by a conformation index >0.

Safety of Switching From a Vitamin K Antagonist to a Non-Vitamin K Antagonist Oral Anticoagulant in Frail Older Patients With Atrial Fibrillation: Results of the FRAIL-AF Randomized Controlled Trial.

Background: There is ambiguity whether frail patients with atrial fibrillation managed with vitamin K antagonists (VKAs) should be switched to a non-vitamin K oral anticoagulant (NOAC).

Methods: We conducted a pragmatic, multicenter, open-label, randomized controlled superiority trial. Older patients with atrial fibrillation living with frailty (≥75 years of age plus a Groningen Frailty Indicator score ≥3) were randomly assigned to switch from international normalized ratio-guided VKA treatment to an NOAC or to continued VKA treatment.

Coagulation parameters predict COVID-19-related thrombosis in a neural network with a positive predictive value of 98.

Thrombosis is a major clinical complication of COVID-19 infection. COVID-19 patients show changes in coagulation factors that indicate an important role for the coagulation system in the pathogenesis of COVID-19. However, the multifactorial nature of thrombosis complicates the prediction of thrombotic events based on a single hemostatic variable.

Patients With Multiple Myeloma Have a Disbalanced Whole Blood Thrombin Generation Profile.

Background: Multiple myeloma (MM) is associated with a high prevalence of bleeding and an increased risk of thrombo-embolism. MM patients have reduced platelet- and red blood cell (RBC) numbers in blood, which may indicate that the paradoxical hemostasis profile is a consequence of a disturbed platelet and RBC homeostasis.

Objectives: To get better insight in the disbalanced hemostasis of MM patients.

Haemostatic differences between SARS-CoV-2 PCR-positive and negative patients at the time of hospital admission.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with thrombosis. We conducted a cohort study of consecutive patients, suspected of SARS-CoV-2 infection presented to the emergency department. We investigated haemostatic differences between SARS-CoV-2 PCR positive and negative patients, with dedicated coagulation analysis.

Von Willebrand factor, ADAMTS13 and mortality in dialysis patients.

Background: Von Willebrand Factor (VWF) multimers are cleaved into smaller and less coagulant forms by the metalloprotease ADAMTS13. The aim of this study was to investigate the association between VWF and ADAMTS13 and mortality in dialysis patients.

Methods: We prospectively followed 956 dialysis patients.

Fatal cerebral hemorrhage in a patient with thrombotic thrombocytopenic purpura with a normal platelet count during treatment with caplacizumab.

Acquired thrombotic thrombocytopenic purpura (aTTP) is a thrombotic microangiopathy with a severe mortality and morbidity. Caplacizumab has recently been approved in the Netherlands as a new therapeutic option in patients with life-threatening organ failure due to aTTP. We describe the case of a 50 year old patient with aTTP who was referred to our hospital for treatment with caplacizumab.

Open ADAMTS13, induced by antibodies, is a biomarker for subclinical immune-mediated thrombotic thrombocytopenic purpura.

Recently, we showed that ADAMTS13 circulates in an open conformation during the acute phase of immune-mediated thrombotic thrombocytopenic purpura (iTTP). Although the cause of this conformational change remains elusive, ADAMTS13 is primarily closed in iTTP patients in remission with ADAMTS13 activity >50% and undetectable anti-ADAMTS13 autoantibodies, as well as after rituximab treatment, suggesting a role for anti-ADAMTS13 autoantibodies. Therefore, immunoglobulin G from 18 acute iTTP patients was purified and added to closed ADAMTS13 in healthy donor plasma.

[Whether or not to use thromboprophylaxis in patients treated with chemotherapy for malignant disease].

Case Description: A 55-year-old patient with locally advanced pancreatic carcinoma will start Folfirinox. Should he get thromboprophylaxis?

Consideration: Patients with malignant disease have increased risk of venous thromboembolism (VTE). Several types of malignancy, surgery, chemotherapy and metastasis lead to increased risk.

Generation of anti-idiotypic antibodies to detect anti-spacer antibody idiotopes in acute thrombotic thrombocytopenic purpura patients.

In autoantibody-mediated autoimmune diseases, autoantibody profiling allows patients to be stratified and links autoantibodies with disease severity and outcome. However, in immune-mediated thrombotic thrombocytopenic purpura (iTTP) patients, stratification according to antibody profiles and their clinical relevance has not been fully explored. We aimed to develop a new type of autoantibody profiling assay for iTTP based on the use of anti-idiotypic antibodies.

Secondary thrombotic microangiopathy with severely reduced ADAMTS13 activity in a patient with Capnocytophaga canimorsus sepsis: a case report.

Background: The Gram-negative bacillus Capnocytophaga canimorsus may cause a severe illness resembling thrombotic thrombocytopenic purpura (TTP). The pathogenesis and optimal therapy of this secondary thrombotic microangiopathy (TMA) remain uncertain.

Case Report: A 63-year-old Caucasian man was admitted with suspicion for TTP, but blood cultures grew C.

Truncation of ADAMTS13 by Plasmin Enhances Its Activity in Plasma.

ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) cleaves von Willebrand Factor (VWF) multimers to control their thrombogenicity. The fibrinolytic enzyme plasmin can cleave VWF in a similar manner. However, plasmin can also cleave ADAMTS13, which ultimately inactivates it.

Agonist-induced platelet reactivity correlates with bleeding in haemato-oncological patients.

Background And Objective: Prophylactic platelet transfusions are administered to prevent bleeding in haemato-oncological patients. However, bleeding still occurs, despite these transfusions. This practice is costly and not without risk.

Where Does Diffuse Large B-Cell Lymphoma Relapse?

Objective: This study aimed to investigate the anatomic pattern of disease spread at first disease relapse compared with baseline in diffuse large B-cell lymphoma (DLBCL).

Materials And Methods: All patients who were newly diagnosed as having DLBCL between January 2004 and June 2014 who initially achieved complete remission but who eventually developed relapsed disease during follow-up were retrospectively identified. Available histological and imaging data were used to determine which nodal regions and extranodal locations were involved at relapse.