A rapid staphylococcal coagglutination technic to differentiate group A from other streptococcal groups.

A rapid staphylococcal coagglutination technic for differentiating group A from other streptococcal groups properly classified 500 isolates of beta-hemolytic streptococci when compared with the results of a reference capillary precipitin test. Presumptive classification of the same 500 isolates by bacitracin susceptibility produced a significant number of incorrect identifications. The findings further document the inherent inaccuracy of the bacitracin susceptibility test and suggest that the staphylococcal coagglutination technic may be a simple, accurate, inexpensive alternative for identification of group A streptococci.