title: In vitro activities of nine current antibiotics against culprit bacteria in nosocomial infections in an institution in Northern Taiwan.
abstract: BACKGROUND
  In recent years, there has been a rapid worldwide emergence of multidrugresistant (MDR) pathogens, especially in cases of nosocomial infections. This study assesses the in vitro activities of ampicillin/sulbactam, cefpirome, colistin, daptomycin, ertapenem, meropenem, teicoplanin, tigecycline and vancomycin against 208 aerobic bacterial pathogens that caused 197 nosocomial infections in 184 patients.
  
  
  METHODS
  Antimicrobial susceptibility was evaluated by Etest. Broth dilution method was utilized in tigecycline susceptibility testing.
  
  
  RESULTS
  Most (140/208, 67%) of the isolates were facultative Gram-negative bacilli. Of the 31 oxacillin-resistant S. aureus (ORSA) isolates, 16 were susceptible to daptomycin (16/31, 51.6%) according to the breakpoint ≤ 1 μg/ml. All 31 ORSA isolates were susceptible to teicoplanin, and vancomycin but MICs of vancomycin for all 31 ORSA isolates were ≥ 1 μg/ml. Of the 21 isolates of A. baumannii that were multiple-drug-resistant, 19 isolates (19/21, 90%) were susceptible to colistin and 18 isolates (18/21, 86%) sensitive to tigecycline. Of the 22 isolates of E. coli with extended-spectrum beta-lactamase (ESBL), the most susceptible antimicrobial agent were colistin (20/22, 91%), ertapenem (21/22, 96%), meropenem and tigecycline (22/22, 100%). Of the 11 isolates of P. aeruginosa, 6 isolates were susceptible to colistin (6/11, 55%) and all isolates were susceptible to meropenem (11/11, 100%).
  
  
  CONCLUSIONS
  For nosocomial infections caused by MDR-Acinetobacter baumannii, colistin and tigecycline are usually susceptible according to the result of this study. For nosocomial infections caused by ORSA, ORSA has reduced susceptibility to vancomycin, teicoplanin and daptomycin. For MDR-P. aeruginosa, further study is needed.
authors.affiliation: Division of Infectious Diseases, Chang Gung Memorial Hospital at Keelung, Chang Gung University College of Medicine, Taoyuan, Taiwan. Lee.sch@msa.hinet.net
authors.forename: Sai-Cheong
authors.initials: SC
authors.lastname: Lee
authors.forename: Shie-Shian
authors.initials: SS
authors.lastname: Huang
authors.forename: Lai-Chu
authors.initials: LC
authors.lastname: See
authors.forename: Ming-Han
authors.initials: MH
authors.lastname: Tsai
authors.forename: Wen-Ben
authors.initials: WB
authors.lastname: Shieh
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001420:Bacteria, Aerobic / Q000187:drug effects*; D003428:Cross Infection / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans
chemical_list: D000900:Anti-Bacterial Agents