A Case of TypeI Glanzmann's Thrombasthenia Diagnosed by Flow Cytometry

ABSTRACT

Glanzmann's thrombasthenia is a rare autosomal recessive hemorrhagic disorder of platelet function with missing or abnormal platelet plasma membrane glycoprotein IIb-IIIa, which functions as a receptor for fibrinogen. We have experienced a case of thrombasthenia in a 6-year-old female whose chief complaints were easy bruising, frequent epistaxis, arthralgia and swelling of the right ankle joint. Bleeding time was prolonged in the presence of normal platelet levels and the platelet aggregation test showed lack of aggregation after exposure to ADP, epinephrine and collagen, but showed an aggregation response to ristocetin. Platelet analysis by flow cytometry is a successful alternative rapid diagnostic technique for Glanzmann's thrombasthenia patients as well as for carriers of this disease. Flow cytometry technique provides an effective tool for investigating platelet function defects caused by altered expression or deficiency of platelet surface proteins.