Platelet spleen tyrosine kinase is a key regulator of anti-PF4 antibody-induced immunothrombosis.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but serious prothrombotic adverse event following vaccination with adenovector-based COVID-19 vaccines. Laboratory findings indicate that anti-platelet factor 4 (PF4) immunoglobulin G antibodies are the causing factor for the onset of thromboembolic events in VITT. However, molecular mechanisms of cellular interactions, signaling pathways and involvement of different cell types in VITT antibody-mediated thrombosis are not fully understood.

Volumetry as a Criterion for Suboccipital Craniectomy after Cerebellar Infarction.

The aim of this study was to investigate the use of image-guided volumetry in cerebellar infarction during the decision-making process for surgery. Particular emphasis was placed on the ratio of the infarction volume to the cerebellar volume or cranial posterior fossa volume. A retrospective, multicenter, multidisciplinary study design was selected.

Subsequent Vaccination against SARS-CoV-2 after Vaccine-Induced Immune Thrombotic Thrombocytopenia.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but severe complication following vaccination with adenovirus vector-based COVID-19 vaccines. Antibodies directed against platelet factor 4 (PF4) are thought to be responsible for platelet activation and subsequent thromboembolic events in these patients. Since a single vaccination does not lead to sufficient immunization, subsequent vaccinations against COVID-19 have been recommended.

Risk Stratification Before Living Donor Kidney Transplantation in Patients With Preformed Donor-specific Antibodies by Different Crossmatch Methods.

Background: Preformed donor-specific HLA antibodies (DSA) are a well-known risk factor in kidney transplantation. There is still considerable debate, however, about the optimal risk stratification among patients with preformed DSA. Additionally, data on the prognostic value of different crossmatch assays in DSA-positive patients are scarce.

A novel prediction score determining individual clinical outcome 3 months after juvenile stroke (PREDICT-score).

Background: Juvenile strokes (< 55 years) account for about 15% of all ischemic strokes. Structured data on clinical outcome in those patients are sparse. Here, we aimed to fill this gap by systematically collecting relevant data and modeling a juvenile stroke prediction score for the 3-month functional outcome.

Characteristics Associated with COVID-19 Breakthrough Infections after Booster Vaccinations in Healthcare Workers: Insights from the TüSeRe:exact Study.

The prevalence of COVID-19 breakthrough infections in healthcare workers (HCWs) remains an issue of concern. This study examines the different characteristics associated with breakthrough infections in HCWs. From the total participants in the TüSeRe:exact study (n = 1046), we specifically included study participants who had received three vaccinations and were not infected prior to the third vaccination.

Apixaban versus Aspirin for Embolic Stroke of Undetermined Source.

BACKGROUND: Rivaroxaban and dabigatran were not superior to aspirin in trials of patients with embolic stroke of undetermined source (ESUS). It is unknown whether apixaban is superior to aspirin in patients with ESUS and known risk factors for cardioembolism. METHODS: We conducted a multicenter, randomized, open-label, blinded-outcome trial of apixaban (5 mg twice daily) compared with aspirin (100 mg once daily) initiated within 28 days after ESUS in patients with at least one predictive factor for atrial fibrillation or a patent foramen ovale.

Heparin-activated procoagulant platelet assay: a flow cytometry-based functional test for heparin-induced thrombocytopenia.

Background: Functional platelet activation assays are required for the diagnosis of heparin-induced thrombocytopenia (HIT). Due to their sophisticated methodology, they are only available in reference centers.

Objectives: To evaluate the diagnostic accuracy of the flow cytometry-based heparin-activated procoagulant platelet (HAPP) assay in the laboratory diagnosis of HIT.

Endovascular treatment of cerebral sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia.

Introduction: There is little data on the role of endovascular treatment (EVT) of cerebral venous sinus thrombosis (CVST) due to vaccine-induced immune thrombotic thrombocytopenia (VITT). Here, we describe clinical characteristics and outcomes of CVST-VITT patients who were treated with EVT.

Patients And Methods: We report data from an international registry of patients who developed CVST within 28 days of SARS-CoV-2 vaccination, reported between 29 March 2021 and 6 March 2023.

Standardized, risk-adapted induction therapy in kidney transplantation.

Background: The choice of induction therapy in kidney transplantation is often non-standardized and centre-specific. Clinicians can choose between depleting and non-depleting antibodies, which differ in their immunosuppressive capacity and the concomitant risk of infection. We herein present a standardized risk-stratified algorithm for induction therapy that might help to balance the risk of rejection and/or serious infection.

Penumbral Rescue by normobaric O = O administration in patients with ischemic stroke and target mismatch proFile (PROOF): Study protocol of a phase IIb trial.

Rationale: Oxygen is essential for cellular energy metabolism. Neurons are particularly vulnerable to hypoxia. Increasing oxygen supply shortly after stroke onset could preserve the ischemic penumbra until revascularization occurs.

Intensive heart rhythm monitoring to decrease ischemic stroke and systemic embolism-the Find-AF 2 study-rationale and design.

Background: Atrial fibrillation (AF) is one of the most frequent causes of stroke. Several randomized trials have shown that prolonged monitoring increases the detection of AF, but the effect on reducing recurrent cardioembolism, ie, ischemic stroke and systemic embolism, remains unknown. We aim to evaluate whether a risk-adapted, intensified heart rhythm monitoring with consequent guideline conform treatment, which implies initiation of oral anticoagulation (OAC), leads to a reduction of recurrent cardioembolism.

Correlation between Clinical Characteristics and Antibody Levels in COVID-19 Convalescent Plasma Donor Candidates.

COVID-19 convalescent plasma (CCP) with high neutralizing antibodies has been suggested in preventing disease progression in COVID-19. In this study, we investigated the relationship between clinical donor characteristics and neutralizing anti-SARS-CoV-2 antibodies in CCP donors. COVID-19 convalescent plasma donors were included into the study.

Inhibition of GPIb-α-mediated apoptosis signaling enables cold storage of platelets.

Cold storage of platelets has been suggested as an alternative approach to reduce the risk of bacterial contamination and to improve the cell quality as well as functionality compared to room temperature storage. However, cold-stored platelets (CSP) are rapidly cleared from the circulation. Among several possible mechanisms, apoptosis has been recently proposed to be responsible for the short half-life of refrigerated platelets.

Platelet phosphatidylserine is the critical mediator of thrombosis in heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a severe immune-mediated prothrombotic disorder caused by antibodies (Ab) reactive to complexes of platelet factor 4 and heparin. Platelets (PLT) and their interaction with different immune cells contribute to prothrombotic conditions in HIT. However, the exact mechanisms and the role of different PLT subpopulations in this prothrombotic environment remain poorly understood.

Hypofibrinolysis in pediatric patients with veno-occlusive disease in hematopoietic stem cell transplantation.

Purpose: Veno-occlusive disease (VOD) is a serious complication of hematopoietic stem cell transplantation (HSCT) with a high incidence in pediatric patients. This study aimed to detect signs of hypofibrinolysis using thrombelastography.

Methods: In this prospective single-center study, thrombelastographic measurements (EX and TPA tests) were taken during HSCT to detect signs of impaired coagulation, clot formation, or hypofibrinolysis.

Diagnostic Performance of a Particle Gel Immunoassay in Vaccine-Induced Immune Thrombotic Thrombocytopenia.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but serious complication of adenoviral vector-based COVID-19 vaccines. Similar to heparin-induced thrombocytopenia (HIT), antibodies reacting to platelet factor 4 (PF4) are responsible for platelet activation in VITT. The diagnosis of VITT includes the detection of anti-PF4 antibodies.

Membrane oxygenator longevity was higher in argatroban-treated patients undergoing vvECMO.

Background: In severe acute respiratory distress syndrome (ARDS), venovenous extracorporeal membrane oxygenation (vvECMO) can be a lifesaver. However, anticoagulation therapy is mandatory because the nonendothelial extracorporeal surface increases the risk of thromboembolic problems. Heparin is still the most common anticoagulant, but argatroban could be an alternative.

Vaccine Side Effects in Health Care Workers after Vaccination against SARS-CoV-2: Data from TüSeRe:exact Study.

As the Corona Disease 2019 (COVID-19) caused by SARS-CoV-2 persists, vaccination is one of the key measures to contain the spread. Side effects (SE) from vaccination are one of the reasons for reluctance to vaccinate. We systematically investigated self-reported SE after the first, second, and booster vaccinations.

PREDICT-juvenile-stroke: PRospective evaluation of a prediction score determining individual clinical outcome three months after ischemic stroke in young adults - a study protocol.

Background: Although of high individual and socioeconomic relevance, a reliable prediction model for the prognosis of juvenile stroke (18-55 years) is missing. Therefore, the study presented in this protocol aims to prospectively validate the discriminatory power of a prediction score for the 3 months functional outcome after juvenile stroke or transient ischemic attack (TIA) that has been derived from an independent retrospective study using standard clinical workup data.

Methods: PREDICT-Juvenile-Stroke is a multi-centre (n = 4) prospective observational cohort study collecting standard clinical workup data and data on treatment success at 3 months after acute ischemic stroke or TIA that aims to validate a new prediction score for juvenile stroke.