Persistence of group A β-hemolytic streptococci in toothbrushes and removable orthodontic appliances following treatment of pharyngotonsillitis

Objective: To investigate the persistence of group A beta-hemolytic streptococci (GABHS) in toothbrushes and removable orthodontic appliances (ROAs) in children who suffer from acute GABHS pharyngotonsillitis and the association with penicillin treatment failure. Setting: Private practice setting. Patients and Methods: Pharyngotonsillar and toothbrush cultures were obtained from 104 children with acute GABHS pharyngotonsillitis before and after 10 days of penicillin V potassium therapy. Cultures of ROAs were also obtained from 21 children. The persistence of GABHS in 10 daily rinsed and 10 nonrinsed toothbrushes was studied in vitro. Results: Group A beta-hemolytic streptococci were isolated from 11 (11%) of the toothbrushes and 18 (17%) of the patients after the completion of penicillin therapy. Toothbrushes of 5 (28%) of the 18 children who harbored GABHS were colonized with the organism. Group A beta-hemolytic streptococci were also isolated from 4 (19%) of 21 ROAs after therapy. In vitro studies illustrated the persistence of GABHS in nonrinsed toothbrushes for up to 15 days. In contrast, the organism was not isolated from rinsed toothbrushes beyond day 3. Conclusion: Toothbrushes and ROAs that harbor GABHS map contribute to the persistence of GABHS in the oropharynx and may account for the failure of penicillin therapy in some cases of pharyngotonsillitis.