FDA-approved susceptibility test result interpretive criteria for tigecycline

PathogenMIC (μg/ml)aDisk diffusion (zone diam, mm)
S. aureus ≤0.5≥19
Streptococcus spp. other than S. pneumoniae≤0.25≥19
E. faecalis (vancomycin susceptible only)≤0.25≥19
Enterobacteriaceae b ≤24≥8≥1915-18≤14
  • a The current absence of resistant isolates precludes defining any results other than “susceptible.” Isolates yielding MIC results suggestive of the “nonsusceptible” category should be submitted to a reference laboratory for further testing.

  • b Tigecycline has decreased in vitro activity against Morganella spp., Proteus spp., and Providencia spp.