THE PATHOLOGY AND MECHANISM OF ANAPHYLAXIS

Abstract

The physiologic disturbances together with gross and microscopic changes accompanying anaphylaxis are of the same character as those of poisoning with peptone and those of traumatic shock. They indicate that underlying mechanisms are the same, being cellular rather than humoral. The cells are irritated and injured, causing increased functional activity if injury is mild. When injury is severe the inflammatory reaction is no different from that which follows other injuries. The capillary endothelium is possibly the chief point of injury in anaphylaxis; the capillaries respond with loss of tonus. There is an increased permeability due to a direct effect of the antigen upon the sensitized endothelial cells rather than indirectly by the injury of tissue cells which by liberating H-substance cause capillary dilatation. The fundamental capillary reactions are identical whether wheals, tissue inflammation, or systemic circulatory failure are produced by anaphylaxis or by trauma.