Summary
A group of patients with clinical hemorrhagic disease who exhibited a prolonged bleeding
time and a short prothrombin consumption time classified as Thrombocytopathy A were
studied utilizing procedures involving isolated platelets and purified prothrombin.
These frozen and thawed platelet extracts had poor platelet factor 3 activity which
was normal after the extracts had been treated with ultrasonic oscillations. The electron
microscope studies of the morphology of these platelets were abnormal. It is concluded
that these platelets contain adequate amounts of platelet factor 3 but are resistant
to disintegration and the activity is only liberated with difficulty.
The authors wish to thank Miss Jeanne M. Riddle, M.S. medical technologist in Hematology
at Henry Ford Hospital for technical assistance in providing the platelet counts for
this investigation.
