Defining the group A streptococcal toxic shock syndrome. Rationale and consensus definition. The Working Group on Severe Streptococcal Infections

GROUP A streptococcus (Streptococcus pyogenes) may cause a variety of illnesses ranging from very common, usually clinically mild conditions such as pharyngitis and impetigo to less common severe infections including septicemia and pneumonia. In 1987, Cone et al1described two patients with severe group A streptococcal infections having clinical features similar to the staphylococcal toxic shock syndrome. This syndrome, designated the "streptococcal toxic shock—like syndrome" or the "toxic streptococcal syndrome,"2was further characterized by Stevens et al3in a series of 20 patients. Most patients included in this series were less than 50 years old and otherwise healthy. All had invasive group A streptococcal infections characterized by signs including shock, multi—organ system involvement, and rapidly progressive, destructive soft-tissue infection (necrotizing fasciitis). The case-fatality rate was 30% even though most patients received appropriate antimicrobial therapy, supportive care, and, where necessary, surgical débridement. Ten available isolates were serotyped and