Table 1.
In vitro activity of old antibiotics against most common gram-negative bacteria.
| Antimicrobial Compound | No. of Isolates (Ref.) | Mechanism b | MIC Range (mg/L) | MIC50 (mg/L) |
MIC90 (mg/L) |
ECOFF c |
|---|---|---|---|---|---|---|
| Colistin | ||||||
| E. coli | 6014 a | NA | 2–128 | 0.5 | 1 | 2 |
| 715 [13] | ESBL | NA | ≤0.25 | 0.5 | ||
| K. pneumoniae | 1841 a | NA | 0.125–512 | 0.5 | 1 | 2 |
| 21 [14] | CRKP | 0.25–2 | ||||
| 633 [13] | ESBL | NA | 0.5 | 2 | ||
| P. aeruginosa | 19,270 a | NA | 0.06–128 | 1 | 2 | 4 |
| 698 [13] | MDR | NA | 1 | 2 | ||
| A. baumannii | 2879 a | NA | 0.5–32 | 1 | 2 | [2] |
| 106 [15] | NA | 0.125–32 | 0.5 | 1 | ||
| 75 [16] | CRAB | 0.5–2 | 1 | 2 | ||
| Polymyxin B | ||||||
| E. coli | 17,035 [17] | NA | NA | ≤0.5 | ≤0.5 | |
| 86 [18] | All including ESBL | 0.064–8 | 0.125 | 0.25 | ||
| K. pneumoniae | 96 [19] | CRE | 0.5–16 | 2 | 2 | |
| 173 [20] | CRE | ≤0.125–>64 | 2 | 32 | ||
| 186 [18] | All including ESBL | 0.064–4 | 0.25 | 0.5 | ||
| P. aeruginosa | 8705 [21] | NA | ≤1–>8 | ≤1 | 2 | |
| 124 [22] | CRPsA included | NA | 1 | 2 | ||
| A. baumannii | 18 [23] | OXA-23 | 0.06–0.5 | 0.25 | 0.25 | |
| 131 [18] | All including CRAB | 0.125–>32 | 0.25 | 0.5 | ||
| Temocillin | ||||||
| E. coli | 5702 a | NA | 0.125–512 | 8 | 32 | 16 |
| 105 [24] | ESBL | 2–32 | 8 | 16 | ||
| 162 [25] | ESBL | 1–64 | 8 | 16 | ||
| 198 [26] | CTX-M | 0.125–>128 | 8 | 16 | ||
| 293 [27] | CTX-M | 2–64 | 8 | 16 | ||
| 40 [27] | AmpC | 2-64 | 8 | 16 | ||
| K. pneumoniae | 605 a | NA | 0.5–512 | 2 | 256 | 8 |
| 23 [28] | Non-CTX-M ESBL | 4–32 | 16 | 32 | ||
| 199 [27] | CTX-M | 2–64 | 8 | 32 | ||
| P. aeruginosa | 104 [29] | NA | 64–≥256 | ≥256 | ≥256 | |
| A. baumannii | 51 [29] | NA | 2–≥256 | ≥256 | ≥256 | |
| Fosfomycin | ||||||
| E. coli | 2351 a | NA | 0.125–512 | 1 | 4 | 4 |
| 35 [30] | ESBL | ≤0.5–1024 | 1 | 32 | ||
| 24 [31] | KPC, MBL, OXA-48 |
≤0.25–256 | 1 | 256 | ||
| 528 [32] | ESBL | NA | NA | 2 | ||
| K. pneumoniae | 1396 a | NA | 0.5–512 | 32 | 256 | 128 |
| 50 [30] | KPC | 8–>2048 | 32 | >2048 | ||
| 27 [30] | NDM, OXA-48 | 16–>2048 | 512 | >2048 | ||
| 50 [31] | KPC, MBL, OXA-48 |
0.5–>1024 | 16 | 256 | ||
| P. aeruginosa | 701 a | NA | 1–512 | 64 | 128 | 256 |
| Mecillinam | ||||||
| E. coli | 1502 a | NA | 0.03–512 | 0.125 | 2 | [0.5] |
| 198 [26] | CTX-M | 0.125–>128 | 1 | 8 | ||
| 30 [33] | Resistance to C3G | 0.5 | 4 | |||
| 29 [34] | NDM | 0.5–32 | 4 | 8 | ||
| K. pneumoniae | 175 a | NA | 0.03–512 | 0.25 | 128 | |
| 24 [34] | NDM | 2–>32 | 8 | >32 | ||
| Nitrofurantoin | ||||||
| E. coli | 4000 a | NA | 1–256 | 16 | 16 | 64 |
| 105 [24] | ESBL | 2–512 | 16 | 64 | ||
| 528 [32] | ESBL | NA | NA | 64 | ||
| Minocycline | ||||||
| E. coli | 1498 a | NA | 0.125–64 | 1 | 16 | 4 |
| K. pneumoniae | 938 a | NA | 0.125–64 | 2 | 16 | 8 |
| 70 [35] | KPC | 0.06–64 | 4 | 16 | ||
| 164 [36] | CP-Kp | NA | 8 | 32 | ||
| A. baumannii | 539 [37] | MDR | 0.06–8 | 2 | >8 | |
| 401 [37] | XDR | 0.06–8 | 2 | >8 | ||
| Chloramphenicol | ||||||
| E. coli | 45,852 a | NA | 1–256 | 4 | 8 | 16 |
| K. pneumoniae | 65 a | NA | 1–256 | 4 | 8 | |
| A. baumannii | 202 [38] | MDR | ≤2–≥32 | ≥32 | ≥32 |
a Data from www.eucast.org, accessed on 23 October 2022. b Abbreviations: NA = Not Available information, mostly WT, MDR = Multiple Drug Resistance, ESBL = Extended Spectrum Beta-Lactamase, CRKP = Carbapenem-resistant K. pneumoniae, CRAB = Carbapenem-resistant Acinetobacter baumannii, CRE = carbapenem-resistant Enterobacterales, CRPsA = Carbapenem-resistant Pseudomonas aeruginosa, OXA = Oxacillinase, KPC = Klebsiella pneumoniae carbapenemase, MBL = Metallo-β-lactamase, NDM = New Delhi metallo beta lactamase, AmpC = Ampicillinase C. c Tentative ECOFF are in brackets. Cells are left empty when no data are available.