Extracellular factors, blood group antigens, and bacteriophage of nephritogenic and nonnephritogenic strains of M-type 12 streptococci.

Strains of M-type 12 streptococci from 18 patients with acute glomerulonephritis and 18 patients with uncomplicated pharyngitis were analyzed for in vitro production of streptolysin O, diphosphopyridine nucleotidase, hyaluronidase, streptokinase, streptolysin S, proteinase, hyaluronic acid, and fibrinogen-precipitating factor. In addition, relations to blood group antigens, lysogeny, and susceptibility to bacteriophage were determined. No significant differences were found between strains from nephritic and nonnephritic patients. By not indicating a role in the pathogenesis of poststreptococcal acute glomerulonephritis for any of the factors studied, these observations diminish the probability that these factors are of specific importance in this disease and thus direct our attention elsewhere.