View clinical trials related to Blood Platelet Disorders.
Filter by:Platelets are essential blood elements to maintain hemostasis. Quantitative or qualitative defects can be responsible of hemorrhagic (platelet disorders) or thrombotic (heparin induced thrombocytopenia [HIT]) troubles. Diagnosis of these pathologies is sometimes urgent and consists in delicate platelet functional assays that are mostly made in expert centers. These platelets functional assays measure platelets activation and/or aggregation in response to diverse inductors and may lack sensitivity. The investigators would like to propose a new diagnostic tool with the use of imaging flow cytometry which provides much more information than classic cytometer on cell morphology thanks to images collected by the optical channel of the ImageStream cytometer. The use of this cytometer offers an innovative approach. This study is a monocentric prospective and non-interventional study. The investigators will analyze patient samples with the ImageStream cytometer and reference laboratory tests (light transmission aggregometry and serotonin release assay) in parallel and compare results from the different techniques. This new diagnostic technique will demonstrate a non-inferiority diagnosis compared to reference tests and maybe a better sensibility.
The effects of chocolate on cardiovascular health are still a matter of debate. It can potentially favor cardiovascular health through the antioxidative effects of cocoa ingredients, such as polyphenols (present in dark but not white chocolate).
In parallel with the growth of American Thrombosis and Hemostasis Network's (ATHN) clinical studies, the number of new therapies for all congenital and acquired hematologic conditions, not just those for bleeding and clotting disorders, is increasing significantly. Some of the recently FDA-approved therapies for congenital and acquired hematologic conditions have yet to demonstrate long-term safety and effectiveness beyond the pivotal trials that led to their approval. In addition, results from well-controlled, pivotal studies often cannot be replicated once a therapy has been approved for general use.(1,2,3,4) In 2019 alone, the United States Food and Drug Administration (FDA) has issued approvals for twenty-four new therapies for congenital and acquired hematologic conditions.(5) In addition, almost 10,000 new studies for hematologic diseases are currently registered on www.clinicaltrials.gov.(6) With this increase in potential new therapies on the horizon, it is imperative that clinicians and clinical researchers in the field of non-neoplastic hematology have a uniform, secure, unbiased, and enduring method to collect long-term safety and efficacy data. ATHN Transcends is a cohort study to determine the safety, effectiveness, and practice of therapies used in the treatment of participants with congenital or acquired non-neoplastic blood disorders and connective tissue disorders with bleeding tendency. The study consists of 7 cohorts with additional study "arms" and "modules" branching off from the cohorts. The overarching objective of this longitudinal, observational study is to characterize the safety, effectiveness and practice of treatments for all people with congenital and acquired hematologic disorders in the US. As emphasized in a recently published review, accurate, uniform and quality national data collection is critical in clinical research, particularly for longitudinal cohort studies covering a lifetime of biologic risk.(7)
This phase II trial studies the side effects and how well avatrombopag works for the treatment of thrombocytopenia after donor hematopoietic stem cell transplant. Thrombocytopenia is defined as abnormally low level of platelets in the blood. Avatrombopag is a small molecule thrombopoietin receptor agonist which stimulates thrombopoietin receptor leading to increase production of platelets.
Circulating blood platelets are small cellular elements that help to control bleeding (a process called hemostasis) and to avoid hemorrhage when blood vessels are injured. Platelets originate from cells in the bone marrow, the megakaryocytes (MKs), following a complex process of morphological transformation and maturation, which finally leads to the production of blood platelets. Multiple genes are implicated in this process. Constitutive thrombocytopenia (CT) are rare hematological diseases characterized by a decreased number of circulating platelets that are often larger than normal, that may lead to more or less severe hemorrhagic events. However, CT can be difficult to diagnose and differentiate from various forms of acquired thrombocytopenia. The ultimate diagnosis for CT is thus based on the molecular diagnosis, obtained by identifying and characterizing the abnormal gene and protein. About 40 genes / proteins have been identified so far as causal in CT, however, in about half of the patients suspected to have CT, genomic analysis does not detect a variant in one of these genes, and etiology of CT thus remains unknown. But insuring the diagnosis of CT is important: it will avoid misdiagnosis and inefficient or deleterious therapeutic interventions, while allowing a proposal of an adapted curative/preventive medical action. At the Resource and Competence Center for Constitutional Hemorrhagic Diseases (CRCMHC) (University Hospital Robert Debré, Paris, France), the investigating team has evidenced in unrelated patients presenting with familial forms of thrombocytopenia and no known molecular diagnosis, variants of genes not yet described as formally implicated in the occurrence of CT. Molecular genetic evidence must be completed by functional studies. Such functional studies are conducted in a research laboratory from the National Institute for Health and Medical Research (Inserm), "Innovative Therapies in Haemostasis (IThEM)" (Faculty of Medical Sciences, University of Paris, Paris, France), and include: - an evaluation of how blood progenitor cells mature into MKs, by comparing cells obtained from patients to those of members free of the disease (the latter taken as normal control subjects); - an evaluation of platelet functionalities, such as ability to form a blood clot similar to what happens during hemostasis, with the aim to detect not only quantitative (number and size) but also any qualitative (functions) defects; - an evaluation of the ultrastructure (the structure of intracellular components) and biochemistry of MKs and platelets, focusing on the molecular pathways the variant protein is implicated in. This clinical trial is aimed to precisely delineate the mechanism of action of newly identified CT genetic variants, and will fulfill the aims of (1) offering the patient(s) a formal molecular diagnosis of CT, (2) ameliorating patients' medical support, both for diagnosis and therapy, (3) providing patients and family members with a pertinent genetic counseling, and (4) expanding the validated panel of genes implicated in CT to be explored in new suspected cases of CT. It will also help in extending the basic knowledge of the process of MK and platelet formation.
This study aims to determine whether cold-stored platelets (CSP) are equally, more effective, or uniquely effective at reversing the effect of dual antiplatelet therapy in healthy human subjects compared to room-temperature-stored platelets (RTP). The investigators plan to enroll healthy human subjects without risk factors for bleeding to achieve 60 complete data sets. Each subject will donate two apheresis platelet units. One platelet unit will be stored in the cold (CSP) and one platelet unit will be stored at room temperature (RTP). Subjects will be given dual anti-platelet therapy (aspirin and clopidogrel) prior to autologous transfusion of each unit. Platelet function testing will be performed before and after transfusion to measure reversal of the antiplatelet drugs.
Kidney biopsy represents the criterion standard to obtain information on diagnosis and prognosis of renal dysfunctions . Many patients with kidney disease have a predisposition to bleed, especially when they undergo an invasive procedure such as renal biopsy. The predominant factor is abnormal platelet function. Therefore, the aim of this study is to evaluate whether the platelet function analyzer (PFA-100), a very reliable test to investigate primary hemostasis, can be useful in predicting the risk of bleeding complications in patients undergoing renal biopsy.
To search for simple laboratory methods selecting patients with low/non-responsiveness to P2Y12 receptor antagonists.
Disorders of platelet function are characterized by variable mucocutaneous bleeding manifestations and excessive hemorrhage following surgical procedures or trauma. Generally, most patients have mild to moderate bleeding manifestations with a prolonged bleeding time. Platelet aggregation and secretion studies using platelet-rich plasma (PRP) provide evidence for platelet dysfunction but are neither predictive of severity of clinical manifestations nor the molecular mechanisms. Glanzmann's thrombasthenia (GT) is a rare autosomal recessive genetic bleeding syndrome characterized by defects in platelet aggregometry. The clinical phenotype of patients with GT is variable. Some suffer from severe bleeding, while others have only mild bleeding. Some studies found bleeding severity in GT was influenced by the abundance and functioning of platelet receptors involved in aggregation and adhesion. In addition to a complete medical history, a GT diagnosis requires a comprehensive laboratory workup, including platelet aggregation analysis, and a confirmation by flowcytometry or western blotting with monoclonal antibodies that recognize the GPIIb/IIIa complex. Platelet flow cytometry is an emerging tool in diagnostic and therapeutic hematology. It is eminently suited to study the expression of platelet surface receptors both qualitatively as well as quantitatively. Aim of the study:- - Determine the role of flowcytometry as a quantitative measurement tool of platelets surface glycoproteins in patients with inherited thrombocytopathies and its correlation with bleeding severity of these patients. - To compare the efficacy, advantages and disadvantages between platelets flowcytometry and aggregometer in diagnosing various inherited thrombocytopathies.
This study will measure primary hemostatic ability using the T-TAS 01 System with PL chip, with a comparison to clinical truth.