Aspirin-induced thrombocytopenia on an immune basis
A patient developed thrombocytopenic purpura 12 hours after he had taken two tablets containing acetylsalicyclic acid and caffeine (Anacin). The platelet count returned to normal seven days after the onset of petechiae. The in vitro platelet factor 3 immunoinjury test for antiplatelet antibody revealed a titer of 1:20 in the presence of Anacin or aspirin alone. No antibody was detected with caffeine or sodium salicylate.