CERTAIN SPECIFIC AND NONSPECIFIC SKIN REACTIONS

Reactions superficially more or less like the focal reactions in certain infectious diseases may develop under other conditions. Thus on the reinjection of therapeutic serum an acute reaction may develop at the site of the previous injection.¹ It would seem that the cells at the point of the first injection have been changed in some way so that they react sharply with substances absorbed from the second injection. The Shwartzman phenomenon is at least somewhat analogous. This phenomenon has been studied extensively in experiments on rabbits and other animals by Shwartzman² and others. As originally observed, it concerns a hemorrhagic and necrotic process at the site of a primary intradermal injection of a bacterial filtrate when followed in twenty-four hours or so by the intravenous injection of a different filtrate. Here the primary injection so changes the condition at its site that a sharp local reaction develops when