Table 1.

MICs of individual agents against penicillin-susceptible, -intermediate, and -resistant S. pneumoniae

S. pneumoniaepenicillin susceptibility (n)Median MIC (range) (μg/ml)
PenicillinTrovafloxacinVancomycinCeftriaxone
Susceptible (15)0.045 (0.03–0.06)0.06 (0.015–0.125)0.5 (0.5–1.0)0.03 (0.03–0.125)
Intermediate (16)0.25 (0.125–0.5)0.06 (0.015–0.25)0.5 (0.5–1.0)0.06 (0.03–2.0)a
Resistant (16)2.0 (2.0–4.0)0.06 (0.015–0.5)0.5 (0.5–1.0)2.0 (0.06–8.0)b
  • a Includes three isolates resistant to ceftriaxone (two isolates with intermediate susceptibility [MIC of >0.5 to 1 μg/ml] and one resistant isolate [MIC of ≥2 μg/ml]).

  • b Includes 14 isolates resistant to ceftriaxone (1 isolate with intermediate susceptibility [MIC of >0.5 to 1 μg/ml] and 13 resistant isolates [MIC of ≥2 μg/ml]).