TABLE 1.

Antimicrobial susceptibility of G. adiacens, G. elegans, and A. defectiva

Antimicrobial agent and species (no. of isolates)	MIC (μg/ml)			Interpretive breakpoint (μg/ml)a or % of isolates
	Range	MIC50	MIC90	Susceptible	Intermediate	Resistant
Penicillin				≤0.12	0.25–2	≥4
G. adiacens (426)	≤0.03 to ≥16	0.25	2	39.4b	50.7b	9.9
G. elegans (20)	≤0.03–8	≤0.03	0.25	80c	15c	5
A. defectiva (152)	≤0.03–8	0.5	8	13.8d	63.2d	23d
Ceftriaxone				≤1	2	≥4
G. adiacens (426)	≤0.06 to ≥32	2	≥16	47.2b	24.4	28.4b
G. elegans (20)	≤0.06 to ≥16	0.12	1	90	5	5
A. defectiva (151)	0.12 to ≥16	0.5	1	98d	1.3d	0.7d
Erythromycin				≤0.25	0.5	≥1
G. adiacens (413)	≤0.12 to ≥8	≥8	≥8	44.6	0.2	55.2
G. elegans (19)	≤0.12 to ≥8	≤0.12	≥8	52.6		47.4
A. defectiva (143)	≤0.12 to ≥8	≥8	≥8	39.9	0.7	59.4
Clindamycin				≤0.25	0.5	≥1
G. adiacens (414)	≤0.03 to ≥32	0.06	≥4	77.3	2.9	19.8
G. elegans (19)	≤0.03 to ≥4	0.12	0.5	89.4	5.3	5.3
A. defectiva (143)	≤0.03–4	0.12	0.25	92.3d	5.6	2.1d
Meropenem				≤0.5	1	≥2
G. adiacens (425)	≤0.06 to ≥16	0.12	0.5	91.3	6.4	2.4
G. elegans (20)	≤0.06–1	≤0.06	0.25	95	5
A. defectiva (150)	0.12–2	0.5	1	80.7d	18.7d	0.6
Levofloxacin				≤2	4	≥8
G. adiacens (414)	≤0.25 to ≥16	1	2	91.6	0.7	7.7
G. elegans (19)	≤0.25–1	0.5	1	100
A. defectiva (144)	0.25–4	≤0.25	0.5	99.3d	0.7	0d
Vancomycin				≤1
G. adiacens (423)	≤0.5–1	1	1	100
G. elegans (20)	≤0.5–1	1	1	100
A. defectiva (152)	≤0.5–1	0.5	1	100
Daptomycin
G. adiacens (343)	≤0.25 to ≥8	4	≥8
G. elegans (19)	≤0.25 to ≥8	0.5	2
A. defectiva (119)	≤0.25–4	2	4
Linezolid
G. adiacens (413)	≤0.25–2	1	1
G. elegans (19)	0.5–1	0.5	1
A. defectiva (143)	≤0.25–2	1	1
Gentamicin
G. adiacens (414)	≤0.12 to ≥16	2	4
G. elegans (19)	0.25–2	1	2
A. defectiva (143)	≤0.12 to ≥16	2	4
TMP/SMX
G. adiacens (391)	≤0.12/2.4 to ≥8/152	0.25/4.8	4/76
G. elegans (18)	0.25/4.8–4/76	0.25/4.8	4/76
A. defectiva (128)	≤0.12/2.4 to ≥4/76	0.25/4.8	0.25/4.8
Doxycycline
G. adiacens (410)	≤0.06 to ≥16	≤0.12	8
G. elegans (19)	≤0.12–8	≤0.12	8
A. defectiva (144)	≤0.06–8	≤0.12	2
Rifampin
G. adiacens (387)	≤0.5 to ≥8	≤0.5	≤0.5
G. elegans (18)	≤0.5	≤0.5	≤0.5
A. defectiva (126)	≤0.5–1	≤0.5	≤0.5

^aInterpretive breakpoints are shown in bold for each antibiotic.

^bP value shows significant differences (P < 0.05) between G. adiacens and G. elegans.

^cP value shows significant differences (P < 0.05) between G. elegans and A. defectiva.

^dP value shows significant differences (P < 0.05) between A. defectiva and G. adiacens.