Table 5.
Cefepime MICs interpretative breakpoints: comparison between CLSI and EUCAST criteria
| Organism | CLSI (MIC, mg/l) |
EUCAST (MIC, mg/l) |
||||
|---|---|---|---|---|---|---|
| S | I | R | S | I | R | |
| Gram-negative | ||||||
| Acinetobacter spp. | ≤8 | 16 | ≥32 | IU | ||
| Burkholderia cepacia | NA | IU | ||||
| Enterobacteriaceae* | ≤8 | 16 | ≥32 | ≤1 | 2-8 | ≥16 |
| Haemophilus spp. | ≤2 | ≤0.25 | ≥0.5 | |||
| Moraxella catarrhalis | NA | ≤0.25 | ≥0.5 | |||
| Neisseria gonorrhoeae | ≤0.5 | IU | ||||
| Neisseria meningitidis | NA | IU | ||||
| Pseudomonas spp. | ≤8 | 16 | ≥32 | ≤8 | ≥16 | |
| Stenotrophomonas maltophilia | NA | IU | ||||
| Gram-positive | ||||||
| Enterococcus spp. | NA | IU | ||||
| Staphylococcus spp. | ≤8 | 16 | ≥32 | ‡ | ||
| Streptococcus pneumoniae | ||||||
| Nonmeningitis | ≤1 | 2 | ≥4 | ≤1 | 2 | ≥4 |
| Meningitis | ≤0.5 | 1 | ≥2 | |||
| Streptococcus spp. | ||||||
| β-hemolytic group | ≤0.5 | ≤0.5 | ≥1 | |||
| Viridans group | ≤1 | 2 | ≥4 | ≤0.5 | ≥1 | |
*
According to CLSI criteria, confirmed E. coli, Klebsiella spp. and P. mirabilis ESBL producers should be reported as resistant to all cephalosporins and aztreonam independently of MIC values [28]. Notably, criteria for the remaining Enterobacteriaceae have not been established.
‡
Susceptibility to cefepime, as with other cephalosporins, is inferred from the methicillin susceptibility.
CLSI: Clinical and Laboratory Standards Institute; EUCAST: European Committee on Antimicrobial Susceptibility Testing; I: Intermediate; IU: Inappropriate use; NA: Not available; R: Resistant; S: Susceptible.