Invasive group A streptococcal infections in children with varicella in Southern California

Objective. To describe demographic and clinical features of invasive group A streptococcal (GAS) infections in children with varicella in Southern California in early 1994. Methods. From hospitals of Los Angeles and Orange Counties, children with invasive GAS infections after varicella between January I and April 8, 1994, were identified by hospital infection control nurses. Medical records of patients were reviewed, and any available GAS isolate was further tested. Results. Twenty-four cases were identified; 54% were male, 50% were Hispanic and the median age was 3 years (range, 0.5 to 8). Four cases died before hospitalization. The other 20 were hospitalized for a median of 10 days (range, 4 to 50): 14 presented with cellulitis (1 with concomitant epiglottitis), 2 with myositis/necrotizing fasciitis, 2 with pneumonia and 2 with bacteremia without apparent source. Five had evidence of multiorgan involvement including two patients fulfilling criteria of streptococcal toxic shocklike syndrome. Of 19 patients with blood cultures, 10 (53%) had GAS bacteremia. Onset of GAS infection was suggested, as a median, on Day 4 of varicella, with fever, vomiting and localized swelling being commonly reported. The mean maximum temperature on the day of admission was 39.4°C (102.9°F). Four GAS isolates were M1T1 and one was M3T3. Five isolates produced streptococcal pyrogenic exotoxins A and B. Conclusions. Invasive GAS disease, including streptococcal toxic shock-like syndrome, is a serious complication of varicella. Physicians should be alert for the complication of GAS when fever and localized swelling or signs of cellulitis develop 3 days or more after the onset of varicella. Widespread use of varicella vaccine may decrease invasive GAS infections in this setting.