title: Congenital defects of platelet function.
abstract: Congenital abnormalities of platelet function disorder (PFD) are associated with the heightened risk for bleeding. Typically, patients with PFDs have mucocutaneous bleeding of variable severity and excessive hemorrhage after surgery or trauma. The diagnostic laboratory assessment appropriate for the evaluation of suspected inherited PFD should be based on a two-step diagnostic strategy: the first step, based on screening tests, helps raising a diagnostic hypothesis, which should then be tested in the second step, which is based on the use of specific tests. The first step should include: complete blood cell count, examination of the peripheral blood smear, and assessment of platelet aggregation. Although light transmission aggregometry (LTA) is the most widely used platelet function test, it is relatively insensitive to defects of platelet secretion; for this reason, laboratory tests that measure platelet aggregation and secretion simultaneously, such as lumi-aggregometry, should be preferred to traditional LTA. The second step includes specific tests (e.g., flow cytometry, Western blotting, DNA analysis). Platelet transfusions should be used only to treat severe bleeding episodes. Recombinant Factor VIIa can be used in patients with severe bleeding episodes who do not respond to platelet transfusion because of alloimmunization. Fibrinolytic inhibitors or the vasopressin analogue desmopressin (DDAVP) should be used in all other circumstances.
authors.affiliation: Medicina III, Azienda Ospedaliera San Paolo, Milano, Italy.
authors.forename: Gianmarco
authors.initials: G
authors.lastname: Podda
authors.forename: Eti Alessandra
authors.initials: EA
authors.lastname: Femia
authors.forename: Mariateresa
authors.initials: M
authors.lastname: Pugliano
authors.forename: Marco
authors.initials: M
authors.lastname: Cattaneo
mesh_terms: D001772:Blood Cell Count; D001791:Blood Platelet Disorders / Q000150:complications / Q000151:congenital / Q000175:diagnosis* / Q000628:therapy*; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology; D015153:Blotting, Western; D003894:Deamino Arginine Vasopressin / Q000627:therapeutic use*; D015942:Factor VIIa / Q000627:therapeutic use*; D005434:Flow Cytometry; D006470:Hemorrhage / Q000150:complications / Q000151:congenital / Q000175:diagnosis* / Q000628:therapy*; D006490:Hemostatics / Q000627:therapeutic use*; D006801:Humans; D010974:Platelet Aggregation / Q000187:drug effects; D010979:Platelet Function Tests; D017713:Platelet Transfusion; D011994:Recombinant Proteins / Q000627:therapeutic use; D017422:Sequence Analysis, DNA
chemical_list: D006490:Hemostatics; D011994:Recombinant Proteins; C103587:recombinant FVIIa; D015942:Factor VIIa; D003894:Deamino Arginine Vasopressin