Antibiotic susceptibility according to genotype of penicillin-binding protein and macrolide resistance genes, and serotype of Streptococcus pneumoniae isolates from community-acquired pneumonia in children.
OBJECTIVE
Antibiotic susceptibilities, genes mediating beta-lactam and macrolide resistance, and serotypes were analysed for strains of Streptococcus pneumoniae.


METHODS
A total of 392 strains of S. pneumoniae were isolated from paediatric patients with community-acquired pneumonia between May 2002 and 2004. All strains were classified into six genotype patterns according to the mutations found in the pbp1a, pbp2x and pbp2b genes identified by PCR. These results are represented by adding 'g', indicating genotypic identification.


RESULTS
Thirty-nine per cent of the isolates showed mutations in either one or two PBP genes (gPISP, where PISP stands for penicillin-intermediate resistant S. pneumoniae) and 52.3% had mutations in three genes (gPRSP, where PRSP stands for penicillin-resistant S. pneumoniae). The majority of the strains had a macrolide resistance gene: mefA, (30.6%); ermB, (48.5%); or both mefA and ermB, (7.7%). The most frequent serotypes of these strains were: 6B (23.2%), 23F (17.6%), 19F (17.3%), 14 (10.5%) and 6A (8.2%). Serotypes of the seven-valent conjugate vaccine covered 70.9% of all isolates, and 89.8% of gPRSP. Serotypes of the strains with cefotaxime MICs of > or =2 mg/L were almost all of a vaccine type.


CONCLUSIONS
The results suggest that introduction of conjugate vaccines into infants and children is necessary for the prevention of pneumococcal infections in Japan.
Chiba
Naoko
N
Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo, 108-8641, Japan.
Kobayashi
Reiko
R
Hasegawa
Keiko
K
Morozumi
Miyuki
M
Nakayama
Eiichi
E
Tajima
Takeshi
T
Iwata
Satoshi
S
Ubukata
Kimiko
K
D019881:Aminoacyltransferases / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D002648:Child; D017714:Community-Acquired Infections / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007223:Infant; D018942:Macrolides / Q000494:pharmacology*; D008565:Membrane Proteins / Q000235:genetics; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D009154:Mutation; D046915:Penicillin-Binding Proteins / Q000235:genetics*; D011008:Pneumococcal Infections / Q000382:microbiology*; D018410:Pneumonia, Bacterial / Q000382:microbiology; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D018942:Macrolides; C117866:MefA protein, Streptococcus; D008565:Membrane Proteins; D046915:Penicillin-Binding Proteins; C072223:PBP 2x protein, Streptococcus; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase; D019881:Aminoacyltransferases; C478701:penicillin-binding protein 2b, Streptococcus