Rheumatic Fever in Children and Adolescents: A Long-term Epidemiologic Study of Subsequent Prophylaxis, Streptococcal Infections, and Clinical Sequelae: VI. Clinical Features of Streptococcal Infections and Rheumatic Recurrences

Abstract

This paper describes the clinical features of 285 streptococcal infections and 48 rheumatic recurrences found in 431 children and adolescents receiving antimicrobial prophylaxis after episodes of rheumatic fever. The patients were examined at monthly intervals for 5 to 6 years. The percentages of different symptomatic types in the identified streptococcal infections that occurred despite prophylaxis seemed no different in these patients than in analogous patients not receiving prophylaxis. Of the 285 infections 41% were asymptomatic, and only 22% produced the classical symptoms of sore throat and fever. The rheumatic fever recurrence rate per infection was directly related to the symptomatic severity of the infection. The rate was 10.3% for asymptomatic infections, 12.0% for symptomatic afebrile infections, 22.7% for febrile infections without sore throat, and 31.7% for infections with fever and sore throat. Although the clinical severity of a streptococcal infection in these patients was a useful clue to its rheumatogenicity, more than half the rheumatic recurrences came without preceding symptoms or with a streptococcal "warning" of atypical symptoms only. The latent period between symptoms of streptococcal infection and onset of recurrent rheumatic fever was more than 2 weeks in 17 (49%) and more than 4 weeks in 13 (37%) of the 35 rheumatogenic infections that were symptomatic. Similar variations in the latent period have been found in other studies of endemic and epidemic situations, with and without use of prophylaxis. Evidence of associated Group A streptococcal infection was found in every recurrence of rheumatic fever that could receive adequate serologic testing. The incidence of recurrent rheumatic attacks, the presenting symptoms of the attacks, and the cardiac effects were all directly related to the severity of preceding cardiac damage in the host. Compared with patients who had no or only possible cardiac damage before the recurrence, those with mild or severe carditis had a greater incidence of recurrences, fewer arthritic symptoms in the recurrences, and more new carditis with significant residual damage. In patients with no or questionable previous carditis, the recurrent rheumatic attacks left no overt permanent cardiac damage. The results indicate that the symptomatic properties of streptococcal infections and the cardiac properties of rheumatic hosts have important roles in the pathogenesis and effects of recurrences of rheumatic fever.