Tigecycline activity tested against 11808 bacterial pathogens recently collected from US medical centers.

Tigecycline activity was evaluated against 11808 pathogens isolated from 30 US medical centers. Susceptibility testing was performed by reference broth microdilution methods. Tigecycline (MIC(50/90), 0.12/0.25 microg/mL) was highly active against Staphylococcus aureus and coagulase-negative staphylococci, regardless of oxacillin resistance. This glycylcycline (MIC(50), 0.12 microg/mL) was 8- and 16-fold more potent than penicillin and linezolid against enterococci and was the most potent agent tested versus Streptococcus pneumoniae. Against Enterobacteriaceae, tigecycline (MIC(90), 1 microg/mL; 98.9% susceptible) was as active as imipenem. This study demonstrated the sustained potency of tigecycline against contemporary clinically relevant Gram-positive and Gram-negative pathogens; tigecycline resistance was rare (0.3%).