Host factors in the susceptibility of rheumatic patients to streptococcal infections.

In children and adolescents who each had at least one previous episode of rheumatic fever and who were not maintaining effective anti-streptococcal prophylaxis, the attack rates of subsequent streptococcal infections declined with advancing age, but were unaffected by gender, cardiac status, or multiplicity of antecedent rheumatic episodes. The rate of rheumatic recurrence per streptococcal infection fell with advancing age, but rose with increasing amounts of cardiac damage and with multiplicity of previous rheumatic attacks. The results suggest that the underlying clinical features of the host have a greater effect on the rheumatogenicity of an acquired streptococcal infection than on the ability to avoid the infection.