Clinical Microbiology and Antimicrobial Chemotherapy. 2007; 9(2):104-120
Streptococcus pyogenes (group A streptococcus) is one of the most important bacterial pathogen in human. In light of recent reports suggesting global changes in the epidemiology of streptococcal infections, and given the increase in severe clinical manifestations of GAS infection, attention to GAS infections and its laboratory diagnosis is in the rise. This paper describes epidemiology of GAS infections, general characteristics of the pathogen, and virulence factors. Modern classification of beta-hemolytic streptococci and methods of isolation and identification of S. pyogenes are also described. Susceptibility testing and mechanisms of antimicrobial resistance are characterized.