Susceptibility of multi-resistant Gram-negative bacilli in Singapore to tigecycline as tested by agar dilution.
BACKGROUND
Tigecycline is an antibiotic belonging to the glycylcycline class with in vitro activity against most Gram-negative bacteria, other than Pseudomonas aeruginosa. This study investigated the in vitro activity of tigecycline against multi-resistant isolates of Enterobacteriaceae and Acinetobacter spp. isolated from clinical specimens in Singapore.


METHODS
Minimum inhibitory concentrations (MICs) to tigecycline were determined for 173 isolates of multi-resistant Escherichia coli, Klebsiella spp., Enterobacter spp. and Acinetobacter spp. using agar dilution.


RESULTS
The MIC required to inhibit the growth of 90% of organisms varied from 0.5 to 4 mg/L for the study isolates. Based on a resistance breakpoint of >or=8 mg/L, resistance rates varied from 0% to 9%.


CONCLUSIONS
Tigecycline demonstrates good in vitro activity against multi-resistant strains of Enterobacteriaceae, with more variable activity against multi-resistant strains of Acinetobacter spp.
Tan
Thean Yen
TY
Laboratory Medicine Services, Changi General Hospital, Singapore. thean_yen_tan@cgh.com.sg
Ng
Lily S Y
LS
D000150:Acinetobacter / Q000187:drug effects*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects*; D004926:Escherichia coli / Q000187:drug effects; D007709:Klebsiella / Q000187:drug effects; D008911:Minocycline / Q000031:analogs & derivatives* / Q000494:pharmacology; D012846:Singapore; D000078304:Tigecycline
D000900:Anti-Bacterial Agents; D000078304:Tigecycline; D008911:Minocycline