A 6 year 6month-old boy was admitted with complains of severe spontaneou epistaxis and easy brusability. He was one of five siblings, and two of them died of recurred severe epistaxis at their age of six years. There was no history of bleeding tendency to his antecedents and parents, whose marriage was unrelated. Platelet count and partial thromboplastin time were noraml with prolonged bleeding time, but clot retraction was poor. Platelet adhesion(Salzman method) was decreased and platelet aggregation test showed flat curve with no response to epinephrine and ADP. These tests of other were normal. Diagnosis of thrombasthenia was made with the above history and laboratory results.
Adenosine Diphosphate ; Bleeding Time ; Blood Platelets ; Clot Retraction ; Diagnosis ; Epinephrine ; Epistaxis ; Hemorrhage ; Humans ; Male ; Marriage ; Parents ; Partial Thromboplastin Time ; Platelet Aggregation ; Platelet Count ; Siblings ; Thrombasthenia*

A 6 year 6month-old boy was admitted with complains of severe spontaneou epistaxis and easy brusability. He was one of five siblings, and two of them died of recurred severe epistaxis at their age of six years. There was no history of bleeding tendency to his antecedents and parents, whose marriage was unrelated. Platelet count and partial thromboplastin time were noraml with prolonged bleeding time, but clot retraction was poor. Platelet adhesion(Salzman method) was decreased and platelet aggregation test showed flat curve with no response to epinephrine and ADP. These tests of other were normal. Diagnosis of thrombasthenia was made with the above history and laboratory results.
Adenosine Diphosphate ; Bleeding Time ; Blood Platelets ; Clot Retraction ; Diagnosis ; Epinephrine ; Epistaxis ; Hemorrhage ; Humans ; Male ; Marriage ; Parents ; Partial Thromboplastin Time ; Platelet Aggregation ; Platelet Count ; Siblings ; Thrombasthenia*

Glanzmann's thrombasthenia is a rare autosomal recessive hemorrhagic disorder characterized by prolonged bleeding time, ad deficient or absent clot retraction in the presence of normal platelet count. The major underlying abnormality in this disease is grossly defective first-phase aggregation of platelet, which are unresponsive to ADP or other platelet agonists such as epinephrine, collagen, thrombin in any concentration. This disability is caused by a decrease or absence of the platelet membrans glycoprotein IIb-IIIa complex, a member of the integrin family of adhesive receptors involved in cell-cell and cell-matrix fibronectin, and vitronectin On the development of surface labeling technique, a variety of biochemical techniques such as radioimmunoassay, crossed immunoelectrophoresis and SDS-PAGE have been used to study the structure and the function of platelet membrane glycoproteins, and to detect the platelet functional defect. But all of these techniques demand a relatively large amount of homogeneous paletelet population that requires manipulation through isolation and washing procedures before analysis. In order to eliminaste such an intricate procedure, we have applied method for analyzing platelet surface components in whole blood using monoclonal antibody and flow cytometry to recognize the absence of severe reduction of platelet membrane glycoprotien llb-llla complex. Platelet analysis by flow cytometry is a successful alternative rapid diagnostic technique for Glanzmann's thrombasthenia patients as well as well as for carriers of this disease. Fow cytometry technique provides a sensitive tool for investigating platelet functional defects caused by altered expression or deficiency of platelet surface proteins.
Adenosine Diphosphate ; Adhesives ; Bleeding Time ; Blood Platelets* ; Clot Retraction ; Collagen ; Electrophoresis, Polyacrylamide Gel ; Epinephrine ; Fibronectins ; Flow Cytometry* ; Glycoproteins ; Hemorrhagic Disorders ; Humans ; Immunoelectrophoresis, Two-Dimensional ; Membrane Glycoproteins* ; Membrane Proteins ; Membranes* ; Platelet Count ; Platelet Membrane Glycoproteins ; Radioimmunoassay ; Thrombasthenia* ; Thrombin ; Vitronectin