TABLE 1

Phenotypic findings of S. pneumoniae strains with reduced susceptibilities to linezolid

Strain (yr of isolation, state)SerotypeL4 phenotypeMIC (μg/ml)aReference or source
LZDVANPENAMOERYCHLCLITET
0566-02 (2001, GA)19AS20N0.250.250.060.060.12≤20.12≤2This study
3084-03 (2002, GA)19AS20N10.250.120.060.25≤20.5≤2This study
7828-04 (2004, CT)014ΔW65R66b40.522280.12≤2This study
2008227074 (2007, NM)09NQ67R, R72G40.25≤0.03≤0.031>80.06≤2This study
TN33388 (2003, TN)33FΔK68G6940.25≤0.03≤0.03180.25≤222
  • a LZD, linezolid; VAN, vancomycin; PEN, penicillin; AMO, amoxicillin; ERY, erythromycin; CHL, chloramphenicol; CLI, clindamycin; TET, tetracycline. Current CLSI breakpoints: LZD susceptible (S), ≤2 μg/ml; VAN S, ≤1 μg/ml; PEN S, ≤2 μg/ml, PEN resistance (R), ≥8 μg/ml; AMO S, ≤2 μg/ml, and AMO R, ≥8 μg/ml; ERY S, ≤0.25 μg/ml, and ERY R, ≥1 μg/ml; CHL S, ≤4 μg/ml, and CHL R, ≥8 μg/ml; CLI S, ≤0.25 μg/ml, and CLI R, ≥1 μg/ml; and TET S, ≤1 μg/ml, and TET R, ≥4 μg/ml (10).

  • b Δ, Deletion.