Tigecycline Evaluation Surveillance Trial (TEST) – In vitro antibacterial activity against Gram-positive and Gram-negative pathogens in Asia

Abstract number: 1134_02_7

Johnson B., Bouchillon S., Stevens T., Johnson J., Hoban D., Dowzicky M.


Tigecycline, a member of a new class of antimicrobials (glycylcyclines), has been shown to have potent expanded broad spectrum activity against most commonly encountered species responsible for community and hospital acquired infections. The TEST program determined the in vitro activity of tigecycline compared to amikacin, ampicillin, imipenem, cefepime, ceftazidime, ceftriaxone, levofloxacin, minocycline and piperacillin/tazobactam against gram negative rods in addition to linezolid, penicillin and vancomycin for the gram positive species. Isolates were collected from hospitals located in Asia throughout 2004.


A total of 424 clinical isolates were identified to the species level at each participating site and confirmed by the central laboratory. Minimum Inhibitory Concentration (MICs) were determined by the local laboratory using supplied broth microdilution panels and interpreted according to NCCLS guidelines.


Tigecycline's activity was similar to imipenem against Enterobacteriaceae with MIC50/MIC90 of 0.25/1 mcg/ml. Resistance to third generation cephalosporin was found in 63.2% of E. coli and 77.8% of K. pneumoniae consistent with ESBL phenotype. Tigecycline inhibited ESBL and AmpC producers with MICs equal or lesser than 1 mcg/ml. Although similar to other classes of broad spectrum antimicrobial agents against glucose non-fermenters, tigecycline was especially active against Acinetobacter spp. presenting the lowest MIC90 of 1 mcg/ml. Tigecycline successfully inhibited S. aureus with MIC90 of 0.25 mcg/ml regardless of sensitivity or resistance to methicillin. Same phenomenon was noticed against enterococci where tigecycline's MIC90 of 0.12mcg/ml was consistent regardless of vancomycin susceptibility.


Tigecycline's in vitro activity was comparable to or greater than most commonly prescribed antimicrobials. The presented data suggest that tigecycline may be an effective and reliable therapeutic option against both aerobic gram-positive and aerobic gram-negative bacteria, including multi-drug resistant strains regardless of degree or type of resistance.

Session Details

Date: 01/08/2007
Time: 00:00-00:00
Session name: XXIst ISTH Congress
Location: Oxford, UK
Presentation type:
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