Table 2.

MIC values of some key antibiotics against isolates of mcr-1-harboring Escherichia coli (n=5) and Klebsiella pneumoniae (n=4) collected from 16 major teaching hospitals throughout Taiwan in 2017

Bacterial species and isolates	MIC (mg/L)
	E. coli					K. pneumoniae
	1	2	3	4	5	1	2a	3	4b
Amoxicillin–clavulanate	32	8	8	64	8	32	128	64	128
Cefoxitin	128	8	4	128	2	32	128	128	128
Ceftazidime	16	0.5	0.5	32	0.0625	1	512	512	512
Ceftriaxone	16	128	128	128	0.0625	0.25	128	16	128
Cefepime	0.25	4	4	8	0.0625	0.25	128	0.25	128
Piperacillin–tazobactam	4	2	2	8	2	256	256	256	256
Ceftazidime–avibactam	0.12	0.12	0.03	0.25	0.03	0.50	4	2	128
Ceftolozane–tazobactam	1	0.25	0.25	2	0.50	1	64	32	128
Ertapenem	0.03	0.03	0.03	0.03	0.03	0.03	128	1	128
Imipenem	0.25	0.12	0.12	0.25	0.12	0.03	64	0.50	64
Meropenem	0.03	0.03	0.03	0.03	0.03	0.03	128	0.12	128
Ciprofloxacin	128	0.03	0.03	128	8	0.25	128	8	64
Amikacin	2	2	2	2	1	2	1	2	128
Tigecycline	0.25	0.50	0.25	0.50	0.25	1	2	1	0.50

Notes:

^aThis isolate also harbors bla_KPC- and bla_OXA-48-like alleles.

^bThis isolate also harbors the bla_KPC allele.

Abbreviation: MIC, minimum inhibitory concentration.