Host-parasite interaction in the pathogenesis of rheumatic fever.

Recent investigation has delineated some of the bacterial and host factors that may play a role in the pathogenesis of rheumatic fever. Continuing studies support the role of antibodies to crossreactive antigens in human tissues and the group A streptococcal cell in inducing tissue damage associated with this disease. Several specific epitopes have now been defined that are common to the crossreactive antigens. Data from recent outbreaks of rheumatic fever in the USA suggest that mucoid group A streptococcal strains, belonging to serotypes M1, M3, M5, M6 and M18 may have accounted for these outbreaks. While these strains are thought to be rheumatogenic, the exact characteristic(s) that renders them so is yet to be determined.