Table 3.
Activity of delafloxacin and comparators against ABSSSI isolates from Brazilian samples.
| Microorganism/Antimicrobial agent | MIC (mg/L) |
|||||
|---|---|---|---|---|---|---|
| MIC50 | MIC90 | MIC range | %S | %I | %R | |
| Staphylococcus aureus (n=18) | ||||||
| Delafloxacine | ≤ 0.008 | 2 | ≤ 0.008 ‒ 2 | 83.4 | ‒ | 16.6 |
| Levofloxacin | 0.5 | > 4 | 0.12 ‒ > 4 | 5.6 | 66.7 | 27.8 |
| Ciprofloxacin | 1 | > 4 | ≤ 0.008 ‒ > 4 | ‒ | 72.2 | 27.8 |
| Oxacillinb | 4 | > 16 | ≤ 0.5 ‒ > 16 | 50 | ‒ | 50 |
| Vancomycin | 1 | 2 | 1 ‒ 2 | 100 | ‒ | ‒ |
| Teicoplanin | ≤ 0.25 | 0.25 | ≤ 0.25 – 0.5 | 100 | ‒ | ‒ |
| Linezolid | 1 | 2 | 1 ‒ 4 | 100 % | ‒ | ‒ |
| Tetracycline | 2 | > 8 | 0.5 ‒ > 8 | 27.8 | 38.9 | 33.3 |
| MSSA (n=9) | ||||||
| Delafloxacine | ≤ 0.008 | a | ≤ 0.008‒4 | 100 | ‒ | ‒ |
| Levofloxacin | 0.5 | a | 0.12 ‒ > 4 | 11.1 | 66.7 | 22.1 |
| Ciprofloxacin | 1 | a | ≤ 0.008 ‒ > 4 | ‒ | 77.8 | 22.2 |
| Oxacillinb | ≤ 0.5 | a | ≤ 0.5 ‒ 2 | 100 | ‒ | ‒ |
| Vancomycin | 1 | a | ≤ 0.25 ‒ 2 | 100 | ‒ | ‒ |
| Teicoplanin | ≤ 0.25 | a | ≤ 0.25 ‒ 0.25 | 100 | ‒ | ‒ |
| Linezolid | 1 | a | 0.5 ‒ 4 | 100 | ‒ | ‒ |
| Tetracycline | 2 | a | 0.5 ‒ > 8 | 11.1 | 55.6 | 33.3 |
| MRSA (n=9) | ||||||
| Delafloxacine | ≤ 0.008 | a | ≤ 0.008 ‒ 2 | 66.7 | ‒ | 33.3 |
| Levofloxacin | 0.5 | a | 0.5 ‒ > 4 | ‒ | 66.7 | 33.3 |
| Ciprofloxacin | 1 | a | 0.5 ‒ > 4 | ‒ | 66.7 | 33.3 |
| Oxacillinb | > 16 | a | 4 ‒ > 16 | ‒ | ‒ | 100 |
| Vancomycin | 1 | a | 1 ‒ 2 | 100 | ‒ | ‒ |
| Teicoplanin | 0.25 | a | ≤ 0.25 ‒ 0.25 | 100 | ‒ | ‒ |
| Linezolid | 1 | a | 1 ‒ 2 | 100 | ‒ | ‒ |
| Tetracycline | 2 | a | 1 ‒ > 8 | 44.5 | 22.2 | 33.3 |
| CoNS (n=18)* | ||||||
| Delafloxacinc | 0.06 | 1 | ≤ 0.008 ‒ 4 | 83.3 | 5.6 | 11.1 |
| Levofloxacin | 4 | > 4 | 0.25 ‒ > 4 | ‒ | 44.4 | 55.6 |
| Ciprofloxacin | 4 | > 4 | 0.12 ‒ > 4 | ‒ | 38.9 | 61.1 |
| Oxacillinb | 16 | > 16 | ≤ 0.5 ‒ > 16 | ‒ | ‒ | 100 |
| Vancomycin | 2 | 4 | 1 ‒ 4 | 100 | ‒ | ‒ |
| Teicoplanin | 1 | 2 | ≤ 0.25 ‒ 2 | 100 | ‒ | ‒ |
| Linezolid | 0.5 | 4 | 0.25 ‒ 4 | 100 | ‒ | ‒ |
| Tetracycline | 4 | 8 | 1 ‒ > 8 | 33.3 | 5.6 | 61.1 |
| Klebsiella spp. (n=10) | ||||||
| Delafloxacine | 1 | > 4 | ≤ 0008 ‒ > 4 | 30 | ‒ | 70 |
| Levofloxacin | 2 | > 4 | ≤ 0.008 ‒ > 4 | 20 | 10 | 70 |
| Ciprofloxacin | 4 | > 4 | ≤ 0.008 ‒ > 4 | 10 | 10 | 80 |
| Cefepime | 64 | > 64 | ≤ 0.12 ‒ > 64 | 33.3 | ‒ | 77.7 |
| Ceftazidime | 64 | > 64 | 0.25 ‒ > 64 | 40 | ‒ | 60 |
| Imipenem | 1 | 64 | 0.25 ‒ 64 | 50 | ‒ | 50 |
| Meropenem | 4 | 32 | ≤ 0.12 ‒ > 64 | 40 | 10 | 50 |
| Ertapenem | 0.5 | > 64 | ≤ 0.12 ‒ > 64 | 20 | ‒ | 80 |
| Amikacin | 2 | > 64 | 1 ‒ > 64 | 60 | ‒ | 40 |
| Gentamicin | 32 | > 64 | 0.25 ‒ > 64 | 20 | ‒ | 80 |
| Polymyxin B | ≤ 0,25 | 32 | ≤ 0.25 ‒ 64 | 60 | ‒ | 40 |
| Klebsiella pneumoniaed(n=9) | ||||||
| Delafloxacine | 1 | a | 0.06 ‒ > 4 | 22.2 | ‒ | 77.8 |
| Levofloxacin | 4 | a | 0.25 ‒ > 4 | 11.1 | 11.1 | 77.8 |
| Ciprofloxacin | > 4 | a | 0.5 ‒ > 4 | ‒ | 11.1 | 88.9 |
| Cefepime | > 64 | a | ≤ 0.12 ‒ > 64 | 33.3 | ‒ | 77.7 |
| Ceftazidime | 64 | a | 0.25 ‒ > 64 | 33.3 | ‒ | 77.7 |
| Imipenem | 32 | a | 0.25 ‒ 64 | 44.5 | ‒ | 55.5 |
| Meropenem | 32 | a | ≤ 0.12 ‒ > 64 | 33.3 | 11.1 | 55.5 |
| Ertapenem | 64 | a | ≤ 0.12 ‒ > 64 | 11.1 | ‒ | 88.9 |
| Amikacin | 2 | a | 1 ‒ > 64 | 55.5 | ‒ | 44.4 |
| Gentamicin | 32 | a | 0.25 ‒ > 64 | 11.1 | ‒ | 88.9 |
| Polymyxin B | 0.25 | a | ≤ 0.25 ‒ 64 | 55.5 | ‒ | 44.4 |
| Enterobacter cloacae (n=7) | ||||||
| Delafloxacine | 0.03 | a | ≤ 0.008 ‒ 1 | 85.7 | ‒ | 14.3 |
| Levofloxacin | 0.12 | a | 0.03 ‒ 0.25 | 100 | ‒ | ‒ |
| Ciprofloxacin | 0.03 | a | ≤ 0.008 ‒ 0.5 | 85.7 | 14.3 | ‒ |
| Cefepime | 1 | a | ≤ 0.12 ‒ > 64 | 57.1 | 14.3 | 28.6 |
| Ceftazidime | 4 | a | 0.5 ‒ > 64 | 42.9 | 14.3 | 42.9 |
| Imipenem | 1 | a | 0.25 ‒ 4 | 71.4 | 28.6 | ‒ |
| Meropenem | ≤ 0.12 | a | ≤ 0.12 ‒ 4 | 71.4 | 28.6 | ‒ |
| Ertapenem | ≤ 0.12 | a | ≤ 0.12 ‒ 32 | 71.4 | ‒ | 28.6 |
| Amikacin | 2 | a | 0.25 ‒ > 64 | 85.7 | ‒ | 14.3 |
| Gentamicin | 0.25 | a | ≤ 0.12 ‒ 64 | 71.4 | ‒ | 28.6 |
| Polymyxin B | ≤ 0.25 | a | ≤ 0.25 ‒ > 128 | 71.4 | ‒ | 28.6 |
| Pseudomonas spp.f(n=16) | ||||||
| Delafloxacine | 0.25 | 1 | 0.016 ‒ > 4 | 81.3 | 12.5 | 6.2 |
| Levofloxacin | 0.5 | > 4 | 0.03 ‒ > 4 | ‒ | 50 | 50 |
| Ciprofloxacin | 1 | > 4 | 0.016 ‒ > 4 | ‒ | 37.5 | 62.5 |
| Cefepime | 4 | > 64 | ≤ 0.12 ‒ > 64 | ‒ | 50 | 50 |
| Ceftazidime | 8 | 32 | 0.25 ‒ 64 | ‒ | 87.5 | 12.5 |
| Imipenem | 4 | 16 | 0.25 ‒ 16 | ‒ | 43.8 | 56.2 |
| Meropenem | 8 | 32 | 0.25 ‒ 64 | 43.8 | 18.7 | 37.5 |
| Amikacin | 4 | > 64 | 0.5 ‒ > 64 | 68.7 | ‒ | 31.3 |
| Gentamicing | 2 | > 64 | ≤ 0.12 ‒ > 64 | – | ‒ | ‒ |
| Polymyxin B | 0.5 | 1 | ≤ 0.25 ‒ 8 | 93.7 | ‒ | 6.3 |
| Pseudomonas aeruginosa (n=14) | ||||||
| Delafloxacine | 0.25 | 1 | 0.016 ‒ > 4 | 78.7 | 14.2 | 7.1 |
| Levofloxacin | 0.5 | > 4 | 0.03 ‒ > 4 | ‒ | 50 | 50 |
| Ciprofloxacin | 1 | > 4 | 0.016 ‒ > 4 | ‒ | 42.9 | 57.1 |
| Cefepime | 16 | > 64 | 1 ‒ > 64 | ‒ | 42.9 | 57.1 |
| Ceftazidime | 4 | 32 | 0.25 ‒ 64 | ‒ | 85.7 | 14.3 |
| Imipenem | 4 | 16 | 1 ‒ 16 | ‒ | 50 | 50 |
| Meropenem | 8 | 32 | 0.25 ‒ 64 | 42.9 | 14.3 | 42.9 |
| Amikacin | 8 | > 64 | 2 ‒ > 64 | 64.3 | ‒ | 35.7 |
| Gentamicin | 4 | > 64 | 1 ‒ > 64 | g | g | g |
| Polymyxin B | 0.5 | 1 | ≤ 0.25 ‒ 1 | 100 | ‒ | ‒ |
⁎
All CoNS were resistant to oxacillin.
a
It was not possible to calculate the MIC90 because the isolates number was lower than 10.
b
Categorization performed according to BRCAST/EUCAST (2021): S. aureus isolates presenting MIC > 2 mg/L for oxacillin were categorized as resistant to methicillin.
c
All CoNS were classified for delafloxacin according to the breakpoint for S. haemolyticus, preconized by the FDA (2020).
d
Klebsiella spp, Klebsiella oxytoca (1) and Klebsiella pneumoniae (9).
e
AST categorization for delafloxacin according to the breakpoints preconized by the FDA (2020). For the comparators the BRCAST/EUCAST (2021) breakpoint were used.
f
Pseudomonas spp. Pseudomonas aeruginosa (14), Pseudomonas putida (1) and 1 Pseudomonas stutzeri (1).
g
There is no breakpoint established by BRCAST/EUCAST (2021).