The presence of beta-lactamase-producing bacteria as a guideline in the management of children with recurrent tonsillitis.

Thirty-eight children who had recurrent tonsillitis and who were chronic carriers of group A beta-hemolytic streptococci (GABHS) were treated with oral clindamycin. Surface tonsillar cultures, obtained prior to therapy and two weeks after the termination of therapy, were processed for aerobic and anaerobic microorganisms. Mixed aerobic and anaerobic flora were obtained from all cultures. Prior to therapy, the average yield was 9.3 isolates (5.2 aerobes and 4.1 anaerobes) per specimen; after the completion of therapy, the average yield was 5.5 isolates (3.0 aerobes and 2.5 anaerobes). The GABHS were completely eliminated after clindamycin therapy, and the numbers of isolates of Bacteroides spp and Staphylococcus aureus were reduced. Beta-lactamase production was detected prior to therapy in 57 isolates recovered from all tonsillar surfaces. This group included all isolates of S. aureus (15) and Bacteroides fragilis (eight), 19 of 34 Bacteroides melaninogenicus isolates (56 per cent), and seven of 12 Bacteroides oralis isolates (58 per cent). Only four isolates of beta-lactamase-producing bacterial strains were recovered after the conclusion of therapy. Follow-up study of 33 children for eight to 16 months (average, 13 months) showed no recurrence of GABHS in 31.