Table 1.

MIC range, MIC90, and resistance rate of 961 pneumococcal respiratory tract isolates in Germany, 1998-1999

Antimicrobial agentMIC range (mg/liter)MIC90 (mg/liter)Ia(%)Ra (%)
Penicillin G≤008–2066.30.3
Amoxicillin/ clavulanic acid≤008–1060.60
Cefuroxime≤008–40.1250.40.6
Clarithromycin03–≥320.53.07.6
Tetracycline03–≥32160.813.1
Levofloxacin06–81.000.1
Ciprofloxacinb 0.25–81.0N.D.N.D.
  • a Breakpoints (I, intermediate; R, resistant) according to the National Committee for Clinical Laboratory Standards (NCCLS) (8). Penicillin G: 0.12–1 mg/liter, ≥2 mg/liter; amoxicillin/clavulanic acid: 4/2 mg/liter, ≥8/4 mg/liter; cefuroxime: 2 mg/liter, ≥4 mg/liter; clarithromycin: 0.5 mg/liter, ≥1 mg/liter; tetracycline: 4 mg/liter, ≥8 mg/liter; levofloxacin: 4 mg/liter, ≥8 mg/liter.

  • b Ciprofloxacin breakpoints are not available from NCCLS. N.D., no data.