Bacteriologic and immunologic studies on patients with hemolytic streptococcic infections as related to rheumatic fever.

NUMEROUS investigators have studied the antibody responses of patients with either complicated or uncomplicated streptococcic infections, but only a few workers 1 have dealt with more than one or two of the antibodies to the known antigenic components of group A hemolytic streptococci. Moreover, reports which have dealt with the antibody response of patients with streptococcic complications and sequelae rarely included the period of the acute streptococcic infection in the study. Antistreptolysin O and antifibrinolysin have been the two antibodies most commonly studied. Todd 2 originally showed that the serum anti-streptolysin O titer was increased after hemolytic streptococcic infections and during the active stage of rheumatic fever. Tillett, Edwards and Garner 3 were the first to show that the plasma clot of most patients convalescent from acute hemolytic streptococcic infections became resistant to lysis by a standard culture of hemolytic streptococci, and Hadfield, Magee and Perry 4 observed that the