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[Characteristics of group A streptococci isolated from children with non-suppurative complication or severe
K Fujita1, K Murono, M Yoshikawa
1Department of Pediatrics, Asahikawa Medical College.
Insights
Group A Streptococcus strains causing severe infections were analyzed over 15 years. Most isolates produced streptococcal pyrogenic exotoxins (SPEs), particularly SPE B, and were linked to conditions like Henoch-Schönlein purpura.
Area of Science:
- Microbiology
- Infectious Diseases
- Pediatrics
Background:
- Group A Streptococcus (GAS) can cause severe, non-suppurative complications.
- Understanding GAS characteristics is crucial for managing these severe infections.
Purpose of the Study:
- To characterize GAS strains isolated from children with severe infections or non-suppurative complications.
- To investigate the association between M/T-serotypes, streptococcal pyrogenic exotoxin (SPE) production, and clinical outcomes.
Main Methods:
- Retrospective analysis of 29 GAS isolates from sporadic cases between 1977 and 1991.
- Clinical data collection for diagnoses including rheumatic fever, reactive arthritis, CNS complications, glomerulonephritis, Henoch-Schönlein purpura, sepsis, and empyema.
- M/T-serotyping and detection of SPE A, B, and C production.
Main Results:
- The 29 GAS isolates were associated with diverse severe conditions, notably Henoch-Schönlein purpura (11 cases).
- Common M/T-serotypes included 1/1 (10 isolates) and 4/4 (7 isolates).
- All isolates produced at least one SPE (A, B, or C), with SPE B and C being most frequent (13 isolates). Isolates from Henoch-Schönlein purpura cases predominantly produced SPE B or SPEs B and C.
Conclusions:
- GAS strains implicated in severe pediatric infections exhibit varied serotypes and significant SPE production.
- SPE B and C appear to play a role in the pathogenesis of severe GAS infections, particularly Henoch-Schönlein purpura.
Abstract:
We determined the characteristics of group A streptococci isolated from 29 sporadic cases with non-suppurative complication or severe infection during a 15-year period from 1977 to 1991. The clinical diagnoses of children included 4 patients with rheumatic fever, 2 with reactive arthritis, 2 with central nervous system complication, 5 with glomerulonephritis, 11 with Honoch-Schölein purpura, 4 with sepsis and 1 with empyema. Twenty-four strains were isolated from throat swabs, 4 from blood specimens and one from pleural fluid. M/T-serotypes and the number of isolates were as follows; 1/1:10, 3/3:1, 3.3R/3:3, 4/4:7, 5/NT:1, 12/12:3, 18/18:2, 62/12:1, NT/13:1. All 29 isolates had productivity for at least one of streptococcal pyrogenic exotoxins (SPEs) A, B and C. Two strains were positive for A, 2 for A and B, 3 for A, B and C, 9 for B and 13 for B and C. Of 11 isolates from patients with Henoch-Schönlein purpura, 7 and 2 strains were serotyped in M1 and M4, respectively, but none was in M12. Ten of 11 isolates were positive for SPE B or SPEs B and C.