Impact of phenoxymethylpenicillin and clindamycin on microflora in recurrent tonsillitis.

A total of 75 patients with recurrent tonsillitis, between 15 and 44 years of age, were divided into three groups, two of which were treated with antibiotics before surgery. Bacteriological specimens were collected before treatment started and the microflora of the excised tonsils were analyzed. Bacteroides species were found in the tonsils of 83% of the patients, and 50% of these microorganisms were beta-lactamase producers. Other bacteria found were Staphylococcus aureus in 45%, beta-streptococci group A in 4%, and beta-streptococci groups C and G in 24%. Hemophilus species were isolated from 50%, but no strains produced beta-lactamase. Fusobacteria were recovered from 41%; one strain produced beta-lactamase. After administration of phenoxymethylpenicillin in doses of 1 g twice a day for nine days, the beta-streptococci were eliminated, but no change of the amount of S aureus, Hemophilus, Bacteroides, or fusobacteria was seen. Clindamycin in doses of 0.15 g four times daily for nine days diminished almost all bacteria except for the Hemophilus species.