View clinical trials related to Blood Platelet Disorders.
Filter by: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.
The aim of this study is to evaluate whether increased level of hemoglobin A1c (HbA1c) correlates to higher level of platelet reactivity assessed by impedance aggregometry in patients with diabetes mellitus undergoing elective coronary artery bypass grafting (CABG).
In Gaucher disease type I bleeding is a common presenting symptom, that may manifest itself as frequent nose bleeds, easy bruising but can also cause substantial bleeding after surgical or dental procedures and may occur in association with pregnancy or delivery . The bleeding tendency is usually considered to be secondary to thrombocytopenia However 50,000 platelets are enough in healthy people to give a normal bleeding time but are associated with significant bleeding tendencies in Gaucher patients. Bleeding tendency might be attributed by genetic inherited or Gaucher related coagulation factors abnormalities which in some cases stabilize with ERT. However, In other cases the etiology is an abnormality of platelet function. This thrombocytopathy has not been delineated and apart from a few aggregation studies, no systematic analysis has been published that convincingly shows the cause of the disturbed function. While, experience shows that enzyme replacement (ERT, i.e: imiglucerase, Cerezyme®) reduces this bleeding tendency, in part due to the improvement in the thrombocyte count and elevation in coagulation factors, it is less clear what effect ERT has on the thrombocytopathy. This has clinical significance when patients need to be prepared for surgery or delivery or in the event of a major bleed. There is no consensus as to how patients should be prepared or treated. Different centres use different approaches. When the procedure is elective ERT is appropriate but in other situations DDAVP, fresh frozen plasma and platelet infusion are possible treatments. Even activated factor VII has been used when bleeding was not controlled. As in any other coagulation abnormality, treatment should be tailored to the specific cause of the bleeding diathesis. The aim of this study is to define the etiology of platelet dysfunction in Gaucher patients. Hypothesis: The investigators expect to see a difference between platelets activation profile among imiglucerase treated and untreated patients with at least a partial restoration of platelets function due to treatment commencement.