The repeated injection of small doses of horse serum and egg-white in dogs, cats, rabbits, and guinea pigs that have been sensitized to these proteins, causes injury to the cells of various organs and tissues with resulting inflammatory reactions.
The changes are especially marked after intraperitoneal injections in the peritoneum and after intravenous injections in the livers of rabbits and cats, and in the myocardium and kidneys of all groups of animals.
In dogs and rabbits, especially, there develops a well marked nephritis characterized by degeneration and necrosis of the epithelium of the loops of Henle, of the collecting tubules, and less frequently of the convoluted tubules. This is accompanied by an extensive small round cell infiltration of the interstitial tissue and later the formation of connective tissue. Together with these changes there are acute and chronic alterations in the glomeruli of all groups of animals.
Egg-white in large doses is itself injurious to the kidney of animals, but this slight primary toxicity is probably greatly enhanced through previous sensitization of the animal.