Table 1.

In vitro susceptibilities of 138 commonly isolated nonfermenting Gram-negative bacillus isolates to tigecycline and other tetracyclines

Species (no. of isolates)	Drug	MIC (μg/ml)
		Range	Breakpoint interpretationa			MIC50	MIC90
			S	I	R
Achromobacter spp. (33)	Tetracycline	2–256	≤4	8	≥16	256	256
	Doxycycline	0.5–64	≤4	8	≥16	16	64
	Minocycline	0.5–16	≤4	8	≥16	2	8
	Tigecyclineb	0.5–4	≤2	4	≥8	2	4
Alcaligenes faecalis (11)	Tetracycline	4–32	≤4	8	≥16	8	16
	Doxycycline	2–16	≤4	8	≥16	2	8
	Minocycline	1–8	≤4	8	≥16	2	8
	Tigecyclineb	1–8	≤2	4	≥8	2	4
Burkholderia cepacia complex (21)	Tetracycline	0.03–256	≤4	8	≥16	16	64
	Doxycycline	0.06–16	≤4	8	≥16	4	4
	Minocyclinec	0.03–4	≤4	8	≥16	1	2
	Tigecyclineb	0.03–2	≤2	4	≥8	0.5	2
Chryseobacterium gleum-indologenes (11)	Tetracycline	0.06–32	≤4	8	≥16	8	32
	Doxycycline	0.125–16	≤4	8	≥16	1	8
	Minocycline	0.03–2	≤4	8	≥16	0.25	1
	Tigecyclineb	0.03–4	≤2	4	≥8	1	4
Elizabethkingia meningoseptica (15)	Tetracycline	2–128	≤4	8	≥16	32	64
	Doxycycline	1–32	≤4	8	≥16	2	4
	Minocycline	0.06–2	≤4	8	≥16	0.25	0.5
	Tigecyclineb	0.25–8	≤2	4	≥8	2	8
Stenotrophomonas maltophilia (26)	Tetracycline	0.5–64	≤4	8	≥16	8	16
	Doxycycline	1–4	≤4	8	≥16	2	2
	Minocyclined	0.25–2	≤4	8	≥16	0.25	0.5
	Tigecyclineb	0.125–8	≤2	4	≥8	0.5	2
Pseudomonas putida (11)	Tetracycline	0.125–256	≤4	8	≥16	2	16
	Doxycycline	0.06–128	≤4	8	≥16	4	32
	Minocycline	0.06–32	≤4	8	≥16	2	16
	Tigecyclineb	0.25–16	≤2	4	≥8	2	8
Pseudomonas stutzeri group (10)	Tetracycline	0.125–8	≤4	8	≥16	0.5	4
	Doxycycline	0.25–8	≤4	8	≥16	2	8
	Minocycline	0.5–8	≤4	8	≥16	1	4
	Tigecyclineb	0.06–4	≤2	4	≥8	0.25	2

^aS, sensitive; I, intermediate; R, resistant. CLSI categories for other non-Enterobacteriaceae for tetracycline, doxycycline, and minocycline were used (susceptibility at 4 μg/ml, intermediacy at 8 μg/ml, and resistance at 16 μg/ml).

^bBreakpoint recommended by the U.S. Food and Drug Administration when testing Enterobacteriaceae for tigecycline (susceptibility at 2 μg/ml, intermediacy at 4 μg/ml, and resistance at 8 μg/ml).

^cBurkholderia cepacia CLSI breakpoint recommended for minocycline.

^dStenotrophomonas maltophilia CLSI breakpoint recommended for minocycline.