A B S T R A C T The technique of platelet aggregometry provides a simple, quantitative, and specific method for the detection of drug-dependent and isoimmune antiplatelet antibodies. In the presence of antiquinidine antibody, quinidine causes lysis of normal platelets in platelet-rich plasma. The resulting changes in optical density are readily detected in the aggregometer. The initial rate of lysis is a function of the antibody titer, but is relatively independent of the platelet count. In vitro, quinidine produces platelet swelling and inhibits aggregation of platelets by adenosine diphosphate, epinephrine, and collagen. Isoimmune antibodies cause aggregation of platelets in platelet-rich plasma. In studies of a single family the rate of aggregation is proportional to the number of HL-A antigens present on the normal platelets against which the antibody is directed. The simple technique of platelet aggregometry may be a useful adjunct in the selection of compatible donors for platelet transfusion. Serumn derived from patients with idiopathic thromboytopenic purpura did not cause platelet aggregation.
We studied eight patients with intermittent bleeding episodes usually following trauma and associated with the ingestion of medicine known to interfere with platelet function. All patients had a normal or minimally prolonged baseline bleeding time. All had a normal platelet count, glass bead retention test, and platelet serotonin content and a variable pattern of abnormalities in prothrombin consumption and platelet factor 3 availability. However, all showed abnormal platelet aggregation reactions using epinephrine, adenosine diphosphate, and collagen. Following the administration of 975 mg aspirin, our patients' bleeding times became prolonged to a greater extent than the bleeding times of normal controls (range 13 to greater than 20 min). Review of the literature showed approximately 5% of “normal” controls had findings similar to those we report. We believe we are describing a group of individuals with an intermediate form of platelet dysfunction. Although their bleeding diathesis is not as severe as that of patients with platelet dysfunction syndromes previoulsy described, they do bleed significantly when subjected to trauma following the ingestion of drugs such as aspirin. We propose that this defect is common and should be screened for. The aspirin tolerance test is a simple test for detecting these patients.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.