Platelet aggregation in whole blood from patients with Glanzmann's
thrombasthenia
ME Burgess-Wilson, SR Cockbill, GI Johnston and S Heptinstall
We examined platelet aggregation in platelet-rich plasma (PRP) and in whole
blood from two patients with Glanzmann's thrombasthenia. In PRP,
aggregation was measured by monitoring the changes in light absorbance that
occurred in response to aggregating agents; to measure platelet aggregation
in whole blood, we used a platelet counting technique. In PRP, the
patients' platelets showed defective aggregation in response to ADP,
adrenaline, arachidonic acid (AA), and collagen, but normal agglutination
occurred in response to ristocetin. In whole blood, however, platelet
aggregation in response to the aggregating agents appeared to be either
very similar to that which occurred in blood from normal subjects or only
slightly reduced. There was a reduced response to all concentrations of ADP
and to low concentrations of collagen but a normal response to all
concentrations of adrenaline, AA, and higher concentrations of collagen.
Conversely, there seemed to be an increased agglutination response to
ristocetin. The abnormality in our two patients with Glanzmann's
thrombasthenia probably lies in the inability of their platelets to form
large, macroscopic aggregates rather than in platelet aggregation per se.
Volume 69,
Issue 1,
pp. 38-42,
01/01/1987
Copyright © 1987 by The American Society of Hematology
