| Summary: | 碩士 === 高雄醫學大學 === 公共衛生學研究所碩士班 === 92 === Upper respiratory tract infections (URTIs) are usually mild and non-threatening but incur frequent physician visits and tremendous health costs. Streptococcus pneumoniae (S. pneumoniae) and Haemophilus influenzae (H. influenzae) are among the most common community-acquired bacterial respiratory pathogens. The rapid emergence of antibiotic resistant pathogens has complicated the empiric therapy of infections and clinical outcome. In addition, co-existence of S. pneumoniae and H. influenzae may have great implications in medical interventions. The purpose of this study was to investigate the antimicrobial susceptibility and the genetic diversity of S. pneumoniae and H. influenzae strains recovered from outpatients of community clinics in Taiwan.
This is an active surveillance study. From November 2001 to March 2002 and November 2002 to March 2003, we sample the throat cultures of S. pneumoniae and H. influenzae from outpatients with suspected upper respiratory infection at five community clinics in Taiwan. Five to six colonies with different morphologic features were selected from each throat sample positive for S. pneumoniae or H. influenzae. The genetic diversity of S. pneumoniae was evaluated by serotyping, PCR-RFLP, pulsed-field gel electrophoresis (PFGE), and southern hybridization. We also evaluated the genetic diversity of H. influenzae by serotyping, PFGE, and PCR detection of large resistant plasmid.
Among 1970 patients sampled, 334 of them (334/1970; 16.95%) are positive for S. pneumoniae and/or H. influenzae. Most patients (266/334; 79.6%) were aged <15 years. A total of 1087 S. pneumoniae isolates were identified from 221 patients (221/1970; 11.2%). 122 of those patients (122/221; 55.2%) carried at least one penicillin non-susceptible isolate. 12 of them (12/221; 5.4%) carried heterogeneous S. pneumoniae. There were 491 H. influenzae isolates identified from 137 patients (137/1970; 7.0%). 24 patients (24/334; 7.19%) carried both S. pneumoniae and H. influenzae. Three of them possessed more than one genetically distinct S. pneumoniae and another three had more than one genetically distinct H. influenzae. One patient even carried genetically diverse S. pneumoniae and H. influenzae isolates simultaneously.
Our study for the first time to demonstrate the genetic diversities of S. pneumoniae and H. influenzae isolates from outpatients of community clinics in Taiwan. Further study is warranted to study the extent of genetic diversity in invasive isolates and its impact on empirical antibiotic treatment.
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