title: Updated antibiotic resistance and clinical spectrum of infections caused by Streptococcus pneumoniae in Taiwan: Emphasis on risk factors for penicillin nonsusceptibilities.
abstract: OBJECTIVE
  Streptococcus pneumoniae is one of the leading pathogens causing community-acquired infection with high mortality rates in elderly patients. Emerging antibiotic resistance was found in past decades. Continuous surveillance to monitor changes in antibiotic resistance of S. pneumoniae and associated risk factors are important clinical issues.
  
  
  METHODS
  Isolates of S. pneumoniae collected from six hospitals participating in the Taiwan Surveillance of Antimicrobial Resistance (TSAR) program III (2002) - VI (2008) were enrolled in this study. Bacterial susceptibilities were determined by minimum inhibitory concentration. The clinical data of source patients were collected retrospectively.
  
  
  RESULTS
  A total of 330 nonduplicate S. pneumoniae isolates were enrolled in this study. Sputum was the most common specimen source, followed by pus. The mean age of the source patients was 38 years among these 330 patients, and 247 had various infections caused by S. pneumoniae. The overall in-hospital mortality rate was 6% and most (60%)of the mortality occurred in patients older than 65 years. The mortality rates among the patients age 65 years and older and those age 5 years and younger were 12.9% (9 of 70) and 2.4% (2 of 83), respectively. The rates of nonsusceptibility to penicillin by the meningitis criteria (PNSP-M) were 69.0% in 2002, 81.0% in 2004, 73.7% in 2006, and 74.5% in 2008. Resistance to erythromycin and trimethoprim/sulfamethoxazole remained high. Using multivariate analysis, patients with PNSP isolates were more likely to have a history of antibiotic exposure within the previous 15 days compared with patients with penicillin-susceptible (PSSP) isolates (nonmeningitis criteria: 29.70% vs. 18.34%, p = 0.0288; meningitis criteria: 25.30% vs. 9.88%, p = 0.006). Shock at presentation was the risk factor for in-hospital mortality.
  
  
  CONCLUSIONS
  Our study demonstrated that the rates of penicillin nonsusceptibility among S. pneumoniae remained high in Taiwan during the study period. Previous antibiotic exposure was the only risk factor for subsequent acquisition of penicillin- nonsusceptible S. pneumoniae compared with penicillin-susceptible S. pneumoniae. Judicious antibiotic use is important to control the spread of drug nonsusceptible S. pneumoniae.
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Department of Internal Medicine, Far Eastern Memorial Hospital, Ban-Ciao, Taiwan.
authors.forename: Hsih-Yeh
authors.initials: HY
authors.lastname: Tsai
authors.forename: Tsai-Ling
authors.initials: TL
authors.lastname: Lauderdale
authors.forename: Jann-Tay
authors.initials: JT
authors.lastname: Wang
authors.forename: Yao-Shen
authors.initials: YS
authors.lastname: Chen
authors.forename: Jien-Wei
authors.initials: JW
authors.lastname: Liu
authors.forename: Jeng-Hwa
authors.initials: JH
authors.lastname: Huang
authors.forename: Bor-Hsian
authors.initials: BH
authors.lastname: Hu
authors.forename: Chia-Jui
authors.initials: CJ
authors.lastname: Yang
authors.forename: Daniel Chin-Te
authors.initials: DC
authors.lastname: Lu
authors.forename: Shan-Chwen
authors.initials: SC
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D010403:Penicillin Resistance; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology*; D015995:Prevalence; D012307:Risk Factors; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000302:isolation & purification; D013624:Taiwan / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents