TABLE 3

Antibiotic resistance of all M. abscessus isolatesa

Isolate group (n)AntibioticNo. of isolates/MIC (mg/ml) of:No. (%) resistant isolatesb
0.060.1250.250.51248163264128
Resistant (69)Clarithromycin before induction711131091928 (40.6)
Clarithromycin after induction16868 (98.6)
Amikacin2133510811 (1.4)
Linezolid13210203333 (47.8)
Moxifloxacin136568 (98.6)
Doxycycline16868 (98.6)
Imipenem3145266 (95.7)
Tobramycin9223860 (87.0)
Cefoxitin3234343 (62.3)
Sulfonamides2722221638 (55.1)
Tigecycline41030169ND
Sensitive (31)Clarithromycin before induction29483336 (19.4)
Clarithromycin after induction74741448 (25.8)
Amikacin23159111 (3.2)
Linezolid17101313 (42.0)
Moxifloxacin122830 (96.8)
Doxycycline13031 (100)
Imipenem142630 (96.8)
Tobramycin192130 (96.8)
Cefoxitin272222 (71.0)
Sulfonamides15710818 (58.1)
Tigecycline261076ND
  • a The erm(41) sequevar-dependent resistance of 100 M. abscessus isolates to the antibiotics indicated was determined by the microdilution method. The incubation time was 3 days (before) and 14 days (after) induction for CLA and 3 days for the other antibiotics listed.

  • b Resistant isolates were distinguished according to the breakpoint provided by NCCLS document M24-A2. ND, no data. Tigecycline has no recommended breakpoint.