Interference by aerobic and anaerobic bacteria in children with recurrent group A beta-hemolylic streptococcal tonsillitis

Objective: To compare the frequency of recovery of aerobic and anaerobic ba cteria with interfering capability of group A beta-hemolytic streptococci ( GABHS) in the tonsils of children with and without a history of recurrent G ABHS pharyngotonsillitis. Patients and Methods: Tonsillar cultures were taken from a group of 20 chil dren with and 20 without history of recurrent GABHS pharyngotonsillitis. Results: Eleven aerobic and anaerobic isolates with interfering capability with GABHS were recovered from 6 (30%) of the 20 children with recurrent GA BHS, and 40 such organisms were isolated from 17 (85%) of the 20 without re currences (P<.01). The interfering organisms included aerobic (alpha-hemoly tic and nonhemolytic streptococci) and anaerobic organisms (Prevotella and Peptostreptococcus species). Conclusions: The tonsils of children with a history of recurrent GABHS infe ction contain fewer aerobic and anaerobic bacteria with interfering capabil ity of GABHS than those without the history of recurrent GABHS infection. T he presence of these interfering bacteria may play a role in preventing GAB HS infection.