Biomaterial Database

Platelet function in autoimmune (idiopathic) thrombocytopenic purpura. 1998

M L Rand, and J A Dean

The Hospital for Sick Children, and Department of Biochemistry, University of Toronto, Ontario, Canada.

Platelets play an essential role in the formation of haemostatic plugs. The quantitative defect of platelets in autoimmune (idiopathic) thrombocytopenic purpura (ITP) can result in bleeding complications, but most ITP patients have platelets with normal or enhanced function. Platelets in ITP are large, young, so-called "stress" platelets with increased platelet-associated autoimmune antibody (immunoglobulin G). Young stress platelets are more functional platelets, and their presence may account for bleeding times in ITP patients that are shorter than would be predicted on the basis of the patients' (low) platelet counts. Some ITP patients have significant mucocutaneous bleeding with platelet counts >50 x 10(9) l(-1); this may be due to qualitative platelet dysfunction (e.g. brought about by inhibitory antiplatelet autoantibodies).

UI	MeSH Term	Description	Entries
D007074	Immunoglobulin G	The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.	Gamma Globulin, 7S,IgG,IgG Antibody,Allerglobuline,IgG(T),IgG1,IgG2,IgG2A,IgG2B,IgG3,IgG4,Immunoglobulin GT,Polyglobin,7S Gamma Globulin,Antibody, IgG,GT, Immunoglobulin
D010974	Platelet Aggregation	The attachment of PLATELETS to one another. This clumping together can be induced by a number of agents (e.g., THROMBIN; COLLAGEN) and is part of the mechanism leading to the formation of a THROMBUS.	Aggregation, Platelet
D010979	Platelet Function Tests	Laboratory examination used to monitor and evaluate platelet function in a patient's blood.	Function Test, Platelet,Function Tests, Platelet,Platelet Function Test,Test, Platelet Function,Tests, Platelet Function
D001792	Blood Platelets	Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.	Platelets,Thrombocytes,Blood Platelet,Platelet,Platelet, Blood,Platelets, Blood,Thrombocyte
D006487	Hemostasis	The process which spontaneously arrests the flow of BLOOD from vessels carrying blood under pressure. It is accomplished by contraction of the vessels, adhesion and aggregation of formed blood elements (eg. ERYTHROCYTE AGGREGATION), and the process of BLOOD COAGULATION.	Hemostases
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001323	Autoantibodies	Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.	Autoantibody
D015539	Platelet Activation	A series of progressive, overlapping events, triggered by exposure of the PLATELETS to subendothelial tissue. These events include shape change, adhesiveness, aggregation, and release reactions. When carried through to completion, these events lead to the formation of a stable hemostatic plug.	Activation, Platelet,Activations, Platelet,Platelet Activations
D016553	Purpura, Thrombocytopenic, Idiopathic	Thrombocytopenia occurring in the absence of toxic exposure or a disease associated with decreased platelets. It is mediated by immune mechanisms, in most cases IMMUNOGLOBULIN G autoantibodies which attach to platelets and subsequently undergo destruction by macrophages. The disease is seen in acute (affecting children) and chronic (adult) forms.	Autoimmune Thrombocytopenic Purpura,Idiopathic Thrombocytopenic Purpura,Purpura, Thrombocytopenic, Autoimmune,Werlhof's Disease,Autoimmune Thrombocytopenia,Immune Thrombocytopenia,Immune Thrombocytopenic Purpura,Thrombocytopenic Purpura, Autoimmune,Werlhof Disease,Autoimmune Thrombocytopenias,Autoimmune Thrombocytopenic Purpuras,Disease, Werlhof,Disease, Werlhof's,Idiopathic Thrombocytopenic Purpuras,Immune Thrombocytopenias,Immune Thrombocytopenic Purpuras,Purpura, Autoimmune Thrombocytopenic,Purpura, Idiopathic Thrombocytopenic,Purpura, Immune Thrombocytopenic,Purpuras, Autoimmune Thrombocytopenic,Purpuras, Idiopathic Thrombocytopenic,Purpuras, Immune Thrombocytopenic,Thrombocytopenia, Autoimmune,Thrombocytopenia, Immune,Thrombocytopenias, Autoimmune,Thrombocytopenias, Immune,Thrombocytopenic Purpura, Idiopathic,Thrombocytopenic Purpura, Immune,Thrombocytopenic Purpuras, Idiopathic,Thrombocytopenic Purpuras, Immune,Werlhofs Disease