[Antimicrobial susceptibility and serotypes of Streptococcus pneumoniae isolated from the patients with respiratory tract infections in Hokusetsu Area of Osaka].

ABSTRACT

One hundred and thirteen strains of Streptococcus pneumoniae (S. pneumoniae) were isolated from the clinical specimens of patients with respiratory tract infections between January and December 1998 in three hospitals in Hokusetsu area of Osaka. We investigated susceptibility of 113 strains of S. pneumoniae to benzylpenicillin (PCG) and other antimicrobial agents and their serotypes. 1) Of the 113 strains of S. pneumoniae isolated, 25.7% were susceptible (PSSP), 51.3% were intermediate (PISP) and 23% were resistant to benzylpenicillin (PRSP). 2) The MICs of cefaclor, cefditoren, cefpodoxime, cefdinir, erythromycin, clindamycin and minocycline were elevated, but the MIC values of cefditoren ranged from < or = 0.03 to 1.0 microgram/ml. The susceptibility of 113 strains to cefditoren was comparatively high. 3) The MIC values of imipenem, meropenem and vancomycin for 81 strains of PISP and PRSP ranged from < or = 0.015 to 1.0 microgram/ml, from < or = 0.015 to 2.0 micrograms/ml and from 0.13 to 0.5 microgram/ml, respectively. The susceptibility of these strains to three antimicrobial agents was superior to that to the other antimicrobial agents examined. 4) Of the 60 strains examined, 19, 6, and 23 serotypes were 30, 25 and 18.3%, respectively. The three serotypes were observed in PISP and PRSP with a high frequency. 5) Isolates of S. pneumoniae were 37.2% for children under 2 years of age and 30.9% for children from 2 to 6 years of age. Most of the strains isolated from these children were resistant.