Bacterial species Reference method MIC breakpoint MIC range; % resistant MIC50 (µ g/ml) MIC90 (µ g/ml) Methods CA ≥ 90% EA ≥ 90% ME ≤ 3% VME ≤3% MiE References 42 A. baumannii isolates BMD S ≤ 2 µ g/ml0.5–4 µ g/ml 1 µ g/ml 2 µ g/ml BMD in glass-coated plates 92.8 100 0 100 [114 ] AD 78.5 92.8 15.4 100 R > 2 µ g/ml0.07% E-test 92.8 16.6 0 100 Vitek 22 AST-N2812 92.8 61.9 0 100 353 isolates BMD S ≤ 2 µ g/mlND ND ND Sensitest 98.9 96 1.46 0.93 [146 ] (83 mcr-1 ) R > 2 µ g/ml38.8% 219 isolates S ≤ 2 µ g/mlND ND ND Phoenix 1003 NMIC-417 96.8 ND 0.6 10 [146 ] R > 2 µ g/ml27.4% 14 E. coli isolates BMD S ≤ 2 µ g/ml0.25–128 µ g/ml; 48% 2 16 Sensititre1 SEMPA1 94.7 96 10.2 0 [143 ] 18 K. pneumoniae isolates R > 2 µ g/ml Micronaut-S 89.3 96 15.4 5.6 21 P. aeruginosa isolates Micronaut-MIC 90.7 99 12.8 5.6 22 Acinetobacter spp. isolates Etest, Oxoid MH 81.3 71 5.1 33.3 Etest, BBL MH 78.7 43 2.6 41.7 Etest, MHE 85.3 47 5.1 25 MTS, Oxoid MH 78.7 40 0 44.4 MTS, BBL MH 76 49 0 50 Sensitest 89.3 88 17.9 2.8 UMIC 92 82 7.7 8.3 117 A. baumannii isolates BMD S ≤ 2 µ g/ml≤0.5–≥16 µ g/ml; 24.8% ≤0.5 8 Vitek 2 AST-XN05 89.7 88.9 1.1 37.9 [129 ] R > 2 µ g/ml Phoenix 100 NMIC/ID-96 88.9 91.5 1.1 41.4 AD 87.2 93.2 15.9 3.4 123 Enterobacteriaceae isolates (14 mcr-1 and 1 mcr-2 ) BMD S ≤ 2 µ g/ml0.12–128 µ g/ml; 67.5% Phoenix 100 NMIC-93 91.8 ND 0 12.1 [83 ] R > 2 µ g/ml Rapid NP 98.3 NA 2.5 1.2 15 Hafnia alvei isolates BMD S ≤ 2 µ g/ml0.125–32 µ g/ml; 96% 8 16 DD 4 NA 0 100 [79 ] 10 Hafnia paralvei isolates R >2 µ g/ml 8 8 Etest 76 32 0 25 Phoenix NMIC-93 100 NA 0 0 Rapid NP 100 NA 0 0 76 Enterobacteriaceae isolates (21 mcr-1 ) BMD S ≤ 2 µ g/ml0.06–>64 µ g/ml; 32.9% 0.25 16 Vitek 2 AST N315 88.2 93.9 0 36 [147 ] R >2 µ g/ml 2 (4) 8 (8) Sensititre GNX3F 90.1 89.5 11.8 4 0.12 0.5 Etest 92.1 75 5.9 12 MicroScan4 NM44 88.2 NA 15.8 4 246 isolates (absence of mcr genes) Broth macrodilution S ≤ 2 µ g/ml≤0.5–>8 µ g/ml; 12.6% ≤0.5 8 Etest 95.1 92.3 0.4 35.5 [160 ] R >2 µ g/ml 41 K. pneumoniae isolates BMD S ≤ 2 µ g/ml2–>128 µ g/ml; 95.1% 8 32 BMD-P80 82 95.1 0 18.9 NA [110 ] 20 A. baumannii isolates R > 2µ g/ml 8 32 AD 91.8 55.7 100 3.4 Etest 59 50.8 33.3 39.3 MTS 67.2 65.6 33.3 41.4 Vitek 2 AST EXN8 96.7 70 66.6 0 290 A. baumannii isolates BMD S ≤ 2 µ g/ml1–128 µ g/ml; 9.3% 2 2 DD 10 µ g (9–12 mm) 94.8 NA 0 0 5.2 [136 ] R > 2 µ g/ml Etest S ≤ 2; R > 4 94.5 2.1 0 55.5 0 Etest S ≤ 0.5; R > 2 99.3 ≡ 0 0 5.5 Vitek 2 AST-N136 94.1 44.8 0.38 59.2 213 Acinetobacter sp. isolates AD S ≤ 2 µ g/ml≤0.5–≥32 µ g/ml; 6.1% 1 2 Vitek 2 AST-N132 99.1 ND 0 15.4 [115 ] R >2 µ g/ml Etest 87.3 1 0 MicroScan panel type 42 99.1 12.5 15.4 60 P. aeruginosa isolates BMD-P80 S ≤ 2 µ g/ml≤0.12–≥8 µ g/ml; 17.8% Broth macrodilution 98 83 2.3 0 [128 ] 20 K. pneumoniae isolates R >2 µ g/ml >8 Etest 91 61 4.5 31.6 27 A. baumannii isolates >8 11 A. baumannii isolates BMD-P80 S ≤ 2 µ g/ml≤0.12–≥8 µ g/ml; 20% >8 BMD 88 34 12.5 10 [128 ] 15 K. pneumoniae isolates R >2 µ g/ml >8 AD 94 80 7.5 0 24 P. aeruginosa isolates Sensititre GNXF 96 62 5 0 11 A. baumannii isolates BMD-P80 S ≤ 2 µ g/ml≤0.12–≥8 µ g/ml; 30% Etest, BBL MH 78 46 5.7 47 [128 ] 15 K. pneumoniae isolates R > 2 µ g/ml Etest, Hardy MH 78 64 2.8 53 24 P. aeruginosa isolates >8 Etest, Remel MH 84 68 2.8 47 109 P. aeruginosa isolates BMD S ≤ 2 µ g/ml0% Phoenix NMIC/ID-76 100 99.1 0 0 [149 ] R >2 µ g/ml 63 E. coli isolates BMD S ≤ 2 µ g/ml0.12–16 µ g/ml; 18.6% 1 BMD-P80 99.2 41.3 0 43.5 [112 ] 61 K. pneumoniae isolates R >2 µ g/ml 0.5 60 Acinetobacter spp. isolates 2 63 P. aeruginosa isolates 2 200 Enterobacteriaceae isolates AD S ≤ 2 µ g/ml0.128–>128 µ g/ml; 28.5% DD 50 µ g; R < 15 mm 96.5 NA 0 12.3 [116 ] 82 K. pneumoniae isolates R > 2 µ g/ml 0.5 128 DD 10 µ g; R ≤ 8; S ≥ 11 mm 93 NA 0 8.8 4.5 51 E. coli isolates 0.5 0.5 DD 10 µ g; R ≤ 11; S ≥ 14 mm 99.5 NA 0 1.7 26.5 67 E. cloacae isolates 0.5 2 Etest 100 52 0 0 0 25 P. aeruginosa isolates AD S ≤ 2 µ g/ml0.25–≥256 µ g/ml; 57.1% 2 >256 BMD 81.1 40.5 0 25 5.4 [120 ] 12 S. maltophilia isolates R > 4 µ g/ml >256 >256 Etest 74.3 56.7 0 35 11.4 DD 10 µ g; R ≤ 10; S ≥ 11 mm 82.8 NA 0 35 2.9 157 E. coli isolates AD S ≤ 2 µ g/ml0.25–32 µ g/ml; 9.6% 0.5 2 DD 150 µ g; R < 16; S ≥ 20 mm 46.5 NA 1.4 20 49.7 [123 ] R >4 µ g/ml DD 10 µ g; 2 + 18H (10–15) 96.8 NA 0.7 13.3 1.9 Etest 96.8 81.5 0.7 0 0.6 78 P. aeruginosa isolates BMD S ≤ 2 µ g/ml<0.25–2 µ g/ml; 0 1 1 Etest 100 79.5 0 0 6.4 [135 ] R > 4 µ g/ml DD 10 µ g 100 NA 100 A. baumannii isolates Phoenix S ≤ 2 µ g/ml 0.5 0.5 DD 10 µ g; R ≤ 8; S ≥ 11 mm 100 NA 0 0 [137 ] R > 4 µ g/ml Etest 100 NA 0 0 154 Acinetobacter spp. isolates AD S ≤ 2 µ g/ml≤0.064–≥32; 11.7% NA NA Etest 98.7 88 0.7 5.6 [124 ] R ≥ 4 µ g/ml 170 Gram-negative isolates AD S ≤ 4 µ g/ml0.25–128; 31.2% Etest 100 91.2 0 0 [126 ] R > 4 µ g/ml 102 Gram-negative isolates BMD S ≤ 2 µ g/ml<0.5–>64 µ g/ml; 50% NA NA AD, Oxoid MH ND 96.8 [31 ] R > 4 µ g/ml AD, Oxoid Iso-Sensitest 97.9 Etest, MH 72.6 Etest, ISO 64.2 Vitek 2 AST N038 93.1 DD 10 µ g; R ≤ 10; S ≥ 13 mm NA 44 Acinetobacter spp. isolates AD S ≤ 2 µ g/ml1-2 µ g/ml; 0 1 2 Vitek 2 AST-N032 100 ND 0 NA NA [118 ] R > 2 µ g/ml 172 Gram-negative isolates AD S ≤ 2 µ g/ml0.5–64; 31.4% Vitek 22 AST-N032 (n = 32) 82 75.2 0 57.4 [32 ] R > 2 µ g/ml Etest (n = 137) 86.6 75.0 6.8 27.8 115 A. baumannii isolates BMD S ≤ 2 µ g/ml≤0.06–512 µ g/ml; 19.1% ≤0.06 32 Etest 98.2 16.5 0 1.7 [138 ] R > 2 µ g/ml 501 P. aeruginosa isolates (401 CF) AD S ≤ 4 µ g/ml≤0.5–≥16 µ g/ml; 17.8% 2 4 BMD 24 h 96 1.2 26.5 [121 ] 50 A. xylosoxidans isolates R >4 µ g/ml 4 ≥16 BMD 48 h 93.6 3.9 18.0 50 S. maltophilia isolates 8 ≥16 70 S. maltophilia AD S ≤ 2 µ g/ml0.12–32 µ g/ml; 24.3% 2 4 DD 10 µ g; R ≤ 8; S ≥ 11 mm 71.2 NA 0 93.7 5.7 [125 ] R > 2 µ g/ml Etest 86.4 96.7 5.6 37.5 NA 200 Gram-negative isolates BMD S ≤ 2 µ g/ml≤1–>128 µ g/ml; 15% DD 10 µ g; R ≤ 10; S ≥ 14 mm 94 NA 0 21.8 1.5 [127 ] (i) 60 A. baumannii isolates R > 2 µ g/ml ≤1 2 DD 10 µ g; R ≤ 8; S ≥ 11 mm 95 0 31.2 1 (ii) 80 P. aeruginosa isolates ≤1 ≤1 (iii) 12 S. maltophilia isolates ≤1 32 35 representatives BMD S ≤ 2 µ g/ml≤1–≥128 µ g/ml; 40% AD 97.1 91.4 47.6 0 [127 ] R > 2 µ g/ml