Pathogenesis of Hemorrhagic-Necrotic Skin Lesions in Intra-dermal Infection of Rabbits with Pneumococci. ∗

Abstract

The hemorrhagic necrotic changes occurring in certain endermal infections of rabbits closely resemble those described by Shwartzman. This induced us to examine various species of pathogenic microorganisms as to their capacity to produce the lesion in question. Previously reported experiments 1-4 revealed 3 different types of reactions represented by the following bacteria:

(1) H. influenzœ, when injected into the skin over the abdomen produces a localized swelling and infiltration. There is no trace of hemorrhagic necrosis to be observed. When, 24 hours after the intracutaneous injection of H. influenzœ, a suspension of H. influenzœ is given intravenously, the site of the dermal infection may be transformed into a bluish hemorrhagic lesion within a few hours. Not only living and heat-killed influenza bacilli but also agar-washing filtrates of B. typhosus, B. coli, or meningococcus may induce the same change. On the other hand, those filtrates may be activated by the intravenous injection of H. influenza. (2) Some strains of Friedländer bacilli spontaneously may induce the formation of hemorrhagic necrotic skin lesions in rabbits. When a heat-killed suspension of such a strain is injected intracutaneously into a rabbit, the site of the infection may be transformed into a hemorrhagic necrotic lesion by means of a subsequent intravenous injection of a suspension of living or heat-killed Friedländer bacilli.