Investigation of oral alpha-streptococcus showing inhibitory activity against pathogens in children with tonsillitis.

The incidence of oral alpha-streptococcus with inhibitory activity against group A streptococcus, as a defense mechanism against bacterial infection in the oral cavity, was investigated in pediatric individuals with tonsillitis. Infection by group A streptococcus appeared to be common in children, because the detection rate of inhibitory alpha-streptococcus in healthy children as well as pediatric patients with tonsillitis was lower than in adults and elderly patients. In particular, the detection rate of these strains was predominantly low in patients with beta-streptococcus. Among pediatric patients scheduled for tonsillectomy, the detection rate of inhibitory alpha-streptococcus was low preoperatively. However, the rate was markedly increased after surgery. The high postoperative detection rate of these strains reflected the decreased incidence of group A streptococcal infection. The results of this investigation of bacterial interference between oral alpha-streptococcus and group A streptococcus suggested that surgical treatment is a more effective approach for improving the oral bacterial flora in children with recurrent tonsillitis.