Non-group A streptococci in the pharynx. Pathogens or innocent bystanders?

OBJECTIVE

To determine whether beta-hemolytic streptococci from groups other than A are an important cause of sporadic pharyngitis in children.

DESIGN

Cross-sectional, case-referent survey.

SETTING

General pediatric clinic at a military base in Ohio.

PARTICIPANTS

One hundred fifty children with symptomatic pharyngitis and 150 controls matched for age and time of presentation over a 20-month study period.

INTERVENTIONS

None.

MEASUREMENTS/MAIN RESULTS: Anaerobic culture technique was used to improve isolation of beta-hemolytic streptococci. Group A beta-hemolytic streptococci were detected significantly more often among the ill children than among the controls (39% vs 16%, respectively). In contrast, non-group A beta-hemolytic streptococci were isolated in similar frequency from the ill and control children (17% vs 21%, respectively). Non-group A beta-hemolytic streptococci from groups B, C, F, and G were each isolated in similar frequency among the ill and control children. The isolation rate of non-group A organisms increased with age among both patients and controls.

CONCLUSIONS

Non-group A beta-hemolytic streptococci seemed not to be an important cause of sporadic pharyngitis in this pediatric population.