In Vitro Activity of β-Lactams in Combination with β-Lactamase Inhibitors against Mycobacterium tuberculosis Clinical Isolates

Table 4

MICs of β-lactams alone or in combination with a fixed concentration of 5 μg/ml of the inhibitor against 122 MTB isolates.

Antibiotic	Inhibitor	MIC range (μg/ml)	MIC50 (μg/ml)	MIC90 (μg/ml)
TBM	None	0.5->16	8	16
	CLA	0.125->16	1	2
	AVI	0.125->16	1	2
	SUB	0.5->16	2	4
BIA	None	2->32	8	16
	CLA	0.25->32	2	4
	AVI	0.5->32	2	4
	SUB	0.5->32	4	8
DOR	None	2->32	16	16
	CLA	0.5->32	2	8
	AVI	0.5->32	4	8
	SUB	0.5->32	4	16
MEM	None	4->32	>32	>32
	CLA	0.25->32	2	8
	AVI	1->32	4	16
	SUB	4->32	8	16
ETP	None	8->32	>32	>32
	CLA	2->32	8	16
	AVI	4->32	8	16
	SUB	4->32	16	32
AMX	None	8->64	>64	>64
	CLA	<0.5-32	2	8
	AVI	<0.5-64	8	16
	SUB	2->64	8	32
AMP	None	32->64	64	>64
	CLA	0.5->64	4	16
	AVI	0.5->64	8	16
	SUB	0.5->64	16	32
CXM	None	16->64	>64	>64
	CLA	1->64	32	>64
	AVI	2->64	32	>64
	SUB	4->64	64	>64

Note: MIC_50/90, MICs that inhibit 50% and 90% of the isolates, respectively.