The induction of rheumatic-like cardiac lesions in rabbits by repeated focal infections with group A streptococci; comparison with the cardiac lesions of serum disease.

Cardiac lesions like those characteristic of rheumatic fever in man have been induced in a small portion of rabbits that were subjected to successive focal infections with group A streptococci of several serological types. Fresh myocardial interstitial granulomata so induced bear striking resemblance to Aschoff bodies, the histologic hallmarks of human active rheumatic fever; and the fresh and healed lesions found in the cardiac valves, endocardia, epicardia, blood vessels, and aortae of some of these rabbits are homologous with those characteristic of rheumatic fever in man. These experimental myocardial and vascular lesions and those of human rheumatic fever differ in several important respects from the lesions of experimental and human serum disease.