伊藤 真人

Recently, a rapid increase in penicillin resistant pneumococci has been reported in most areas of the world. These penicillin resistant bacteria are becoming less susceptible to other commonly prescribed oral antimicrobial drugs, including extended-spectrum cephalosporins. Also, a rapid spread of ampicillin resistant Haemophilus influenzae in children with respiratory tract infections has been reported in Japan. Therefore, we carried out clinical and bacteriological studies of topical treatment of the nasopharynx in patients with pediatric acute otitis media at 3 general hospitals and 6 clinics. Between February and May 2000, 30 strains of Streptococcus pneumoniae and 19 strains of Haemophilus influenzae were isolated from the nasopharynx in 42 children with acute otitis media. Of the 30 Streptococcus pneumoniae, penicillin G resistant S. pneumoniae (PRSP) and penicillin G intermediately resistant S. pneumoniae (PISP) accounted for 55% and 10% of the total, respectively. On the other hand, 26% of the 19 Haemophilus influenzae were β-lactamase-negative ampicillin-resistant (BLNAR) strains. The bacteriological efficacy of topical treatment of the nasopharynx combined with appropriate oral antimicrobial drugs in patients with PRSP, PISP and BLNAR was 57%, 50% and 60%, respectively. On the other hand, the bacteriological efficacy of only oral antimicrobial drugs in patients with PRSP, PISP and BLNAR was 20%, 43% and 63% respectvely. These results suggest that the success rate of the sterilization of pediatric nasopharynxes using a topical treatment combined with oral antimicrobial drugs is higher than treatments using only oral antimicrobial drugs.