A new abnormality of platelet functions. Association of storage pool disease (thrombocytopathia A) with impaired reactivity of platelets to collagen.

Multiple platelet abnormalities were found in a patient with bleeding symptoms. The platelet content of ADP and PF 4 was decreased and the uptake of 14C-serotonin was impaired. The content of acid phosphatase, beta-glucuronidase and beta-N-acetylglucosaminidase was, however, normal and these enzymes were normally released or made available by bovine fibrinogen or ADP. There was no adhesion of platelet to collagen, which also failed to induce reptilase clot retraction, platelet aggregation and release of any of the platelet constituents. The platelets therefore exhibited signs of thrombocytopathy of a combined type with a decreased storage pool as well as a qualitative dysfunction with impaired reactivity to collagen.