Table 2.

MICs of mcr-1-positive Salmonella typhimurium isolates to colistin and other antibiotics (μg/mL)

Antibiotics	16–541	16–573	16–623
Colistin	8 (R)	8 (R)	8 (R)
Levofloxacin	4 (I)	0.25 (S)	4 (I)
Ciprofloxacin	8 (R)	0.125 (S)	8 (R)
Cefotaxime	>256 (R)	>256 (R)	>256 (R)
Cefepime	128 (R)	64 (R)	128 (R)
Cefoperazone/sulbactam	32 (I)	16 (S)	32 (I)
Imipenem	0.5 (S)	0.5 (S)	1 (S)
Meropenem	0.0625 (S)	0.0625 (S)	0.0625 (S)
Amikacin	8 (S)	4 (S)	16 (S)
Tigecycline	1 (S)	0.5 (S)	1 (S)
Fosfomycin	0.25 (S)	64 (R)	0.25 (S)
Sulfamethoxazole/trimethoprim	>32 (R)	>32 (R)	>32 (R)
Aztreonam	8 (I)	4 (S)	16 (R)

Abbreviations: MIC, minimum inhibitory concentration; I, intermediate; R, resistant; S, susceptible.