Severe Group A Streptococcal Infections Associated with a Toxic Shock-like Syndrome and Scarlet Fever Toxin A

TLDR

Concern exists that group A streptococci, historically causing less severe infections in developed countries, may be acquiring increased virulence. The study reports on 20 Rocky Mountain patients with group A streptococcal infections from 1986–1988 characterized by extensive local tissue destruction and life‑threatening systemic toxicity. Among these patients, necrotizing fasciitis (55 %) was most common, 95 % experienced shock, 80 % had renal impairment, 55 % developed ARDS, the mortality rate was 30 %, most had no underlying disease, and 8 of 10 isolates produced pyrogenic exotoxin A, indicating a resurgence of highly virulent strains. Published in N Engl J Med 1989; 321:1–7.

Abstract

There is concern that group A streptococci, which have caused less serious infections in developed countries in recent decades, may be acquiring greater virulence. We describe 20 patients from the Rocky Mountain region who had group A streptococcal infections from 1986 to 1988 that were remarkable for the severity of local tissue destruction and life-threatening systemic toxicity. Among the 20 patients (median age, 36), necrotizing fasciitis with or without myositis was the most common soft-tissue infection (55 percent). Nineteen patients (95 percent) had shock, 16 (80 percent) had renal impairment, and 11 (55 percent) had acute respiratory distress syndrome. The mortality rate was 30 percent. All patients but 1 had positive tissue cultures for Streptococcus pyogenes; 12 had positive blood cultures. Most of the patients had no underlying disease; 2 used intravenous drugs. Strains of group A beta-hemolytic streptococci isolated from 10 patients were not of a single M or T type; however, 8 of the 10 strains produced pyrogenic exotoxin A (scarlet fever toxin A, a classic erythrogenic toxin), which has rarely been observed in recent years. From our study of this cluster of severe streptococcal infections with a toxic shock-like syndrome, we conclude that in our region, more virulent group A streptococci have reappeared that produce the pyrogenic toxin A associated with scarlet fever. (N Engl J Med 1989; 321:1–7.)