Table 1.
Subspecies/Antimicrobial Agents | MIC50 MIC90 Range | Susceptibility % (n) | erm(41) | ||||
---|---|---|---|---|---|---|---|
Sequevars (n) | |||||||
(µg/mL) | R | I | S | ||||
Mycobacterium abscessus subsp. abscessus (n=97) | |||||||
Aminoglycosides | |||||||
Amikacin | 16 | 32 | 2–>64 | 4.1 | 30.9 | 63.9 | T(28) 86; |
Tobramycin | 16 | >16 | 2–>16 | 91.8 | 6.2 | 2.1 | C(28) 10 |
Cephalosporins | Truncated(1) | ||||||
Cefoxitin | 64 | 128 | 16–>128 | 34.0 | 56.7 | 9.3 | |
Cefepimea | >32 | >32 | 32–>32 | 100 | 0 | 0 | |
Ceftriaxonea | >64 | >64 | 32–>64 | 99 | 1 | 0 | |
Carbapenem | |||||||
Imipenem | 16 | 64 | 2–>64 | 41.2 | 45.4 | 13.4 | |
Fluoroquinolones | |||||||
Ciprofloxacin | >4 | >4 | 2–>4 | 93.8 | 6.2 | 0 | |
Moxifloxacin | >8 | >8 | 0.5–>8 | 94.9 | 3.1 | 2.1 | |
Folate pathway inhibitor | |||||||
SXT | >8 | >8 | 1–>8 | 94.9 | – | 5.1 | |
Tetracyclines | |||||||
Tigecycline | 1 | 4 | 0.12–>4 | 11.3 | – | 88.7 | |
Minocyclinea | >8 | >8 | 4–>8 | 94.9 | 3.1 | 2.1 | |
Doxycycline | >16 | >16 | 0.5–>16 | 87.6 | 8.3 | 4.1 | |
Macrolide | |||||||
Clarithromycin - 3days | 1 | 16 | 0.06–>16 | 14.4 | 0 | 85.6 | |
Clarithromycin - 14days | 16 | >16 | 0.06–>16 | 88.7 | 0 | 11.3 | |
Oxazolidinone | |||||||
Linezolid | >32 | >32 | 2–>32 | 86.6 | 8.3 | 5.2 | |
β-Lactam/β-lactamase inhibitor combinations | |||||||
AMCa | >64 | >64 | 32–>64 | 99 | 1 | 0 | |
Mycobacterium abscessus subsp. massiliense (n=13) | Truncated(13) | ||||||
Aminoglycosides | rrl(1) | ||||||
Amikacin | 16 | 32 | 8–32 | 0 | 38.5 | 61.5 | |
Tobramycin | >16 | >16 | 4–>16 | 92.3 | 7.7 | 0 | |
Cephalosporins | |||||||
Cefoxitin | 64 | 128 | 32–128 | 46.1 | 53.9 | 0 | |
Cefepimea | >32 | >32 | 16–>32 | 92.3 | 7.7 | 0 | |
Ceftriaxonea | >64 | >64 | 64–>64 | 100 | 0 | 0 | |
Carbapenem | |||||||
Imipenem | 16 | 32 | 2–32 | 23.1 | 69.2 | 7.7 | |
Fluoroquinolones | |||||||
Ciprofloxacin | >4 | >4 | 2–>4 | 92.3 | 7.7 | 0 | |
Moxifloxacin | >8 | >8 | 2–>8 | 84.6 | 15.4 | 0 | |
(µg/mL) | R | I | S | ||||
Folate pathway inhibitor | |||||||
SXT | >8 | >8 | 1–>8 | 84.6 | - | 15.4 | |
Tetracyclines | |||||||
Tigecycline | 2 | 4 | 0.5–4 | 15.4 | - | 84.6 | |
Minocyclinea | >8 | >8 | 8–>8 | 100 | 0 | 0 | |
Doxycycline | >16 | >16 | 4–>16 | 84.6 | 15.4 | 0 | |
Macrolide | |||||||
Clarithromycin - 3days | 0.5 | 2 | 0.06–>16 | 7.7 | 0 | 92.3 | |
Clarithromycin - 14days | 0.5 | 2 | 0.06–>16 | 7.7 | 0 | 92.3 | |
Oxazolidinones | |||||||
Linezolid | >32 | >32 | 16–>32 | 76.9 | 15.4 | 7.7 | |
β-Lactam/β-lactamase inhibitor combinations | |||||||
AMCa | >64 | >64 | 16–>64 | 92.3 | 0 | 7.7 | |
Mycobacterium abscessus subsp. bolletii (n=19) | No mutations | ||||||
Aminoglycosides | |||||||
Amikacin | 16 | 32 | 2–64 | 5.3 | 21 | 73.7 | |
Tobramycin | 16 | >16 | 4–>16 | 89.5 | 10.5 | 0 | |
Cephalosporins | |||||||
Cefoxitin | 128 | 128 | 32–>128 | 63.2 | 36.8 | 0 | |
Cefepimea | >32 | >32 | 32–>32 | 100 | 0 | 0 | |
Ceftriaxonea | >64 | >64 | 64–>64 | 100 | 0 | 0 | |
Carbapenem | |||||||
Imipenem | 16 | 32 | 2–32 | 47.4 | 31.6 | 21 | |
Fluoroquinolones | |||||||
Ciprofloxacin | >4 | >4 | 4–>4 | 100 | 0 | 0 | |
Moxifloxacin | >8 | >8 | 2–>8 | 94.8 | 5.2 | 0 | |
Folate pathway inhibitor | |||||||
SXT | >8 | >8 | 2–>8 | 94.5 | - | 5.3 | |
Tetracyclines | |||||||
Tigecycline | 2 | 4 | 0.25–4 | 15.8 | - | 84.2 | |
Minocyclinea | >8 | >8 | 8–>8 | 100 | 0 | 0 | |
Doxycycline | >16 | >16 | 2–>16 | 89.5 | 10.5 | 0 | |
Macrolide | |||||||
Clarithromycin - 3days | 1 | 16 | 0.5–>16 | 26.3 | 0 | 73.7 | |
Clarithromycin - 14days | 16 | >16 | 2–>16 | 94.7 | 0 | 5.3 | |
Oxazolidinone | |||||||
Linezolid | >32 | >32 | 8–>32 | 73.7 | 5.3 | 21 | |
β-Lactam/β-lactamase inhibitor combinations | |||||||
AMCa | >64 | >64 | 64–>64 | 100 | 0 | 0 |
Note: aDrugs out of guidelines.
Abbreviations: R, resistance; I, intermediate; S, susceptible; No mutations, There were no erm or rrl mutations in the M. bolletii isolates; SXT, trimethoprim/sulfamethoxazole; AMC, amoxicillin/clavulanic acid.