PLATELETS AND THE SHWARTZMAN PHENOMENON.

Studies are reported on the effect of immunologically induced thrombocytopenia upon the local and generalized Shwartzman phenomena. Intravenous injection of antiplatelet serum to rabbits produced profound but transient thrombocytopenia unaccompanied by significant changes in circulating leucocytes. Platelet antiserum alone given to rabbits prepared with thorotrast produced renal lesions characteristic of the Shwartzman reaction. Thrombocytopenia induced by platelet antiserum did not inhibit the cutaneous hemorrhagic lesion of the local Shwartzman phenomenon produced by sequential injections of endotoxin intracutaneously and intravenously. The implications of these observations in the pathogenesis of the local cutaneous and generalized Shwartzman reaction are discussed.