Developments in the field of chemotherapy have aroused an increased interest in a more exact bacteriologic differentiation of the various groups of streptococci in order to understand the varied responses of patients suffering from streptococcic infections to sulfanilamide and its derivatives. By means of a precipitation test devised by Lancefield1 the hemolytic streptococci may be divided into nine groups, which are designated by letters of the alphabet. The great majority of virulent human streptococcic infections are caused by members of group A. Organisms of this group commonly form toxic substances, such as hemolysin, fibrinolysin, erythrogenic toxin and leukocidin. Scarlet fever and erysipelas are caused by hemolytic streptococci belonging to group A. The remaining groups of hemolytic streptococci, known as B, C, D, E, F, G, H and K, may cause infection occasionally in man, but such infection is generally mild. Many of them are animal streptococci.
REPORT OF A
KEITH HM, HEILMAN FR. SUBACUTE BACTERIAL ENDOCARDITIS DUE TO HEMOLYTIC STREPTOCOCCI OF LANCEFIELD GROUP G. Am J Dis Child. 1943;65(1):77-80. doi:10.1001/archpedi.1943.02010130086007