Objective: The aim of this study was to review the clinical features, laboratory findings and the risk factors associated with invasive group A streptococcal infections in children admitted to our institution over a 9-year period (January 1, 1990 through December 31, 1999).
Methods: Medical records of children who had a positive blood culture for group A beta-hemolytic streptococci and children who had this organism isolated from any other sterile site were identified and retrospectively reviewed.
Results: Forty-one children with invasive GAS were identified, of whom 15 (36%) were diagnosed between 1990 and 1994, while the balance (26 patients, 63%) were diagnosed between 1995 and 1999 (p< 0.05). The mean age was 4.3 +/- 2.5 years (age range: 2 months to 16 years). Thirteen (32%) patients were infants. Sixteen patients had only bacteremia, while 25 patients had in addition to bacteremia the following: cellulitis (n: 13), osteomyelitis (n: 6), pneumonia (n: 3), meningitis (n: 1), pharyngitis (n:3) and Toxic Shock Syndrome (n: 2). Primary varicella infection constituted the most common predisposing factor for invasive GAS infections and occurred in 11 (27%) patients. Leukocytosis (A white blood cell count > 15,000/mm3) occurred in 21 (51 %) patients, while leukopenia (A white blood cell count < 5000/mm3) occurred in 2 patients. Parenteral crystalline penicillin G followed by oral penicillin or amoxicillin were the most common antibiotics administered. The mean hospital length of stay was 8 days (range: 6 -32 days). All, but one patient survived. The one patient who died had malnutrition and died from streptococcal toxic shock syndrome.
Conclusion: More cases of invasive GAS were diagnosed during the second half of the study period, however, the overall rate of occurrence of bacteremia during the study period was consistent with previous reports. Primary varicella infection was the most common predisposing factor for invasive GAS infections. The low occurrence of toxic shock syndrome and fatalities among children with invasive GAS infections are consistent with other pediatric but not with adult series.