抄録
Platelet function and factor VIII were studied in seventeen patients with CML. The clinical symptom of bleeding tendency was seen in two out of 17 cases.
Prolonged Duke bleeding time was seen in only two out of 14 patients; on the other hand, the Simplate bleeding time was prolonged in five of ten cases. The platelet retention decreased in 13 of 17 patients.
The maximal extent of aggregation induced by ADP, collagen and epinephrine was reduced in 24%, 24% and 41% of patients examined, respectively. The second wave of ADP- and epinephrine-induced aggregation was absent and the lag preceding the onset of collagen induced aggregation was prolonged in platelets with reduced maximal extent of aggregation induced by each aggregating agent. Abnormal ristocetin induced aggregation was seen in nine out of 17 patients. The platelets of all patients were normally aggregated with arachidonic acid.
The intracellular concentrations of ATP and ADP were significantly reduced, and the ratio of ATP/ADP was greater than normal. ATP released from platelets was reduced, as determined by Lumi-aggregometer.
In patients with abnormal ristocetin induced platelet aggregation, FVIIIR: Ag, FVIIIR: CoF and FVIII: C were all decreased. No significant inactivation of factor VIII was induced in normal plasma by its incubation with patient's plasma.
The present study shows that in some patients with CML, acquired von Willebrand's disease may occur.
