Group A Polysaccharide Precipitin Reactions in Acute Streptococcosis and Rheumatic Fever *

The r6le of the beta-hemolytic Streptococcus in the etiology of rheumatic fever has attracted considerable attention for the last twenty or more years. Although epidemiological studies, particularly those indicating a high incidence of streptococcic pharyngitis preceding first attacks or recurrences of rheumatic disease., have furnished highly suggestive evidence of the importance of this organism in the pathogenesis of this disorder, the exact mechanisms involved have not yet been elucidated. The development of a hypersensitivity reaction to Streptococcus pyogenes or to some of its endoor extracellular products has been suggested by many investigators mainly on the basis of two observations: (i) the presence of a "latent period" between the initial streptococcal infection and the subsequent development of rheumatic fever, and (ii) the appearance of various antibodies to the Streptococcus and its products with greater frequency, in higher concentration, and persisting for a longer time in the rheumatic state than in uncomplicated streptococcosis. A large number of studies of specific and non-specific serologic reactions have been carried out in an attempt to characterize the immunological reactive pattern of the rheumatic and to contrast it with uncomplicated streptococcal infection in order to detect differences that might be of help in unmasking the mechanisms involved or in establishing the early diagnosis of the rheumatic state. Investigations of the serum content of anti-streptolysin, anti-streptokinase, anti-M, anti-C, anti-hyaluronidase, anti-X, antitrypsin, C-reactive protein, beta-hemolytic streptococcal agglutinin and bactericidal antibody, among others, have been thought to indicate that some of these appear more frequently, are present in larger quantities, and persist longer in patients with rheumatic fever than in those who have uncomplicated streptococcosis. None of these studies, however, have succeeded in attaching an unquestionable direct causal relationship of any of these immune substances to the pathogenesis of rheumatic fever. Careful evaluation of the voluminous literature on this subject, which cannot be reviewed in this paper because of limitations of space, permits only one conclusion-positive reactions with the various antibodies mentioned above