Experimental observations on the aetiology of rheumatic fever.

In spite of continued research the pathogenesis of rheumatic fever remains a problem of much complexity. In the pursuit of its aetiology during the past 60 years, intensive bacteriological studies have been carried out, metabolic disturbances have been considered, allergic mechanisms have been incriminated, the role of heredity, dietary deficiency and a host of other factors have been investigated, but all with equivocal results. No matter from what angle the problem has been viewed, most workers have been unanimous in the opinion that rheumatic fever is in some obscure manner related to streptococcal infection, and that if this relationship were understood, the evolution of the disease might be elucidated. Since rheumatic fever is a condition which presents a characteristic pathological picture, an important approach to the investigation of its aetiology has been the attempt to reproduce the disease in the experimental animal. It is generally accepted that the Aschoff nodule is a specific lesion, peculiar to rheumatic carditis, and from time to time there have been claims that the process has been duplicated experimentally by a variety of procedures. Recently, interest has been renewed in the experimental approach to the study of the pathogenesis of rheumatic fever, and it may therefore be of value to survey briefly the various experimental observations which have been made.