Table 4.

MICs of eight antimicrobial agents for M. chelonae reported by four laboratories

DrugMIC (μg/ml) for isolatea:
181418311866
Mode (range)% AgreementMode (range)% AgreementMode (range)% Agreement
Amikacin128 (32–256)97.264 (8–128)66.732 (8–64)80.5
Cefoxitin512 (512)100512 (256–512)100512 (256–512)100
Ciprofloxacin32 (2–32)66.78 (2–32)77.816 (2–32)94.4
Clarithromycin0.125 (0.06–0.25)1000.25 (0.03–0.5)88.9128 (8–128)97.2
Doxycycline0.25 (0.25–2)61.164 (32–64)10064 (64)100
Imipenem16 (4–128)88.916 (4–64)86.132 (8–128)75.0
Sulfamethoxazole128 (32–128)91.7128 (32–128)97.2128 (32–128)97.2
Tobramycin8 (4–32)77.82 (1–8)94.42 (1–4)100
  • a % Agreement, percentage of MICs in each three-dilution range (mode ± log2). High off-scale MICs were converted to the next-highest concentration; low off-scale MICs were left unchanged.