TABLE 1.

MICs of agents against anaerobes

Organisma	Drug(s)	MIC (μg/ml)
		Range	50%	90%
Bacteroides fragilis (69/70)	Doripenem	0.125-8	0.25	1
	Imipenem	0.03-2	0.125	0.25
	Meropenem	0.06-8	0.125	1
	Ertapenem	0.125-8	0.25	2
	Piperacillin-tazobactam	≤0.125-8	0.5	1
	Amoxicillin-clavulanate	0.25-4	0.5	2
	Ceftriaxone	≤0.125->128	64	>128
	Clindamycin	0.125->16	1	4
	Metronidazole	0.25-2	1	1
Bacteroides thetaiotaomicron (30/30)	Doripenem	0.25-0.5	0.25	0.5
	Imipenem	0.25-0.5	0.25	0.5
	Meropenem	0.125-0.5	0.25	0.5
	Ertapenem	0.5-2	0.5	1
	Piperacillin-tazobactam	2-32	16	16
	Amoxicillin-clavulanate	0.5-8	1	1
	Ceftriaxone	64->128	>128	>128
	Clindamycin	0.25->16	4	8
	Metronidazole	0.25-2	1	1
Bacteroides ovatus (10/10)	Doripenem	0.25-4	0.25	1
	Imipenem	0.125-2	0.25	0.5
	Meropenem	0.25-4	0.25	0.5
	Ertapenem	0.5-8	0.5	2
	Piperacillin-tazobactam	4-16	4	8
	Amoxicillin-clavulanate	0.5-8	0.5	2
	Ceftriaxone	64->128	64	>128
	Clindamycin	2->16	2	>16
	Metronidazole	0.5-2	1	2
Bacteroides vulgatus (20/20)	Doripenem	0.125-1	0.25	1
	Imipenem	0.06-1	0.5	1
	Meropenem	0.125-1	0.25	1
	Ertapenem	0.06-2	0.125	2
	Piperacillin-tazobactam	0.5-64	8	16
	Amoxicillin-clavulanate	0.5-8	0.5	8
	Ceftriaxone	2->128	16	>128
	Clindamycin	≤0.016->16	0.03	0.5
	Metronidazole	≤0.125-1	0.5	1
Bacteroides distasonis (8/20)	Doripenem	0.25-1	0.5	1
	Imipenem	0.25-1	0.5	1
	Meropenem	0.125-1	0.125	0.5
	Ertapenem	0.5-2	0.5	1
	Piperacillin-tazobactam	4-8	4	8
	Amoxicillin-clavulanate	1-8	2	8
	Ceftriaxone	1->128	8	>128
	Clindamycin	0.03->16	4	>16
	Metronidazole	1-2	1	1
Prevotella bivia (21/30)	Doripenem	0.06-0.25	0.06	0.125
	Imipenem	≤0.016-0.125	0.03	0.06
	Meropenem	0.03-0.25	0.06	0.125
	Ertapenem	0.06-0.5	0.25	0.25
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-4	0.25	4
	Ceftriaxone	≤0.125-128	8	64
	Clindamycin	≤0.016->16	0.03	>16
	Metronidazole	0.5-4	2	2
Prevotella disiens (7/10)	Doripenem	0.03-0.125	0.06	0.125
	Imipenem	0.03-0.125	0.03	0.125
	Meropenem	0.03-0.125	0.03	0.125
	Ertapenem	0.03-0.25	0.06	0.25
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-2	≤0.125	0.5
	Ceftriaxone	≤0.125-64	2	64
	Clindamycin	≤0.016->16	≤0.016	0.03
	Metronidazole	0.5-2	0.5	2
Prevotella intermedia/Prevotella nigrescens (19/30)	Doripenem	≤0.016-0.125	0.03	0.06
	Imipenem	≤0.016-0.06	0.03	0.03
	Meropenem	≤0.016-0.125	0.03	0.06
	Ertapenem	≤0.016-0.125	0.03	0.06
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-1	≤0.125	0.5
	Ceftriaxone	≤0.125-64	4	16
	Clindamycin	≤0.016->16	≤0.016	≤0.016
	Metronidazole	0.25-1	0.5	1
Prevotella melaninogenica/Prevotella denticola (16/20)	Doripenem	≤0.016-0.25	0.03	0.125
	Imipenem	≤0.016-0.125	0.03	0.06
	Meropenem	≤0.016-0.25	0.06	0.25
	Ertapenem	0.03-0.5	0.125	0.5
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-4	0.25	2
	Ceftriaxone	≤0.125-128	4	64
	Clindamycin	≤0.016->16	0.03	0.03
	Metronidazole	≤0.125-1	0.5	1
Prevotella corporis (6/10)	Doripenem	0.03-0.06	0.03	0.06
	Imipenem	≤0.016-0.06	0.03	0.06
	Meropenem	≤0.016-0.06	0.03	0.06
	Ertapenem	≤0.016-0.125	0.03	0.06
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-0.5	≤0.125	0.25
	Ceftriaxone	≤0.125-32	4	32
	Clindamycin	≤0.016-1	≤0.016	0.03
	Metronidazole	0.25-1	0.5	1
Prevotella buccae (3/10)	Doripenem	0.06-0.125	0.06	0.125
	Imipenem	0.03-0.06	0.03	0.03
	Meropenem	0.06-0.06	0.06	0.06
	Ertapenem	0.06-0.125	0.125	0.125
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-2	≤0.125	1
	Ceftriaxone	≤0.125-64	0.25	4
	Clindamycin	≤0.016-0.03	≤0.016	0.03
	Metronidazole	0.5-2	1	1
Porphyromonas asaccharolytica (0/4)	Doripenem	≤0.016-0.03
	Imipenem	≤0.016-0.03
	Meropenem	≤0.016
	Ertapenem	≤0.016
	Piperacillin-tazobactam	≤0.125
	Amoxicillin-clavulanate	≤0.125
	Ceftriaxone	≤0.125
	Clindamycin	≤0.016
	Metronidazole	≤0.125-0.25
Porphyromonas gingivalis (0/3)	Doripenem	≤0.016
	Imipenem	≤0.016
	Meropenem	≤0.016
	Ertapenem	≤0.016
	Piperacillin-tazobactam	≤0.125
	Amoxicillin-clavulanate	≤0.125
	Ceftriaxone	≤0.125
	Clindamycin	≤0.016
	Metronidazole	≤0.125
Porphyromonas levii (0/1)	Doripenem	0.03
	Imipenem	≤0.016
	Meropenem	≤0.016
	Ertapenem	≤0.016
	Piperacillin-tazobactam	≤0.125
	Amoxicillin-clavulanate	≤0.125
	Ceftriaxone	≤0.125
	Clindamycin	≤0.016
	Metronidazole	≤0.125
Fusobacterium nucleatum (2/20)	Doripenem	≤0.016-0.03	≤0.016	0.03
	Imipenem	≤0.016-0.06	0.03	0.03
	Meropenem	≤0.016-0.06	≤0.016	0.03
	Ertapenem	≤0.016-0.06	≤0.016	0.03
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-0.5	≤0.125	≤0.125
	Ceftriaxone	≤0.125-0.5	0.25	0.5
	Clindamycin	0.03-0.125	0.06	0.125
	Metronidazole	≤0.125-0.5	≤0.125	≤0.125
Fusobacterium necrophorum (0/18)	Doripenem	≤0.016-0.25	≤0.016	0.25
	Imipenem	≤0.016-0.25	≤0.016	0.25
	Meropenem	≤0.016-0.125	≤0.016	0.125
	Ertapenem	≤0.016-0.125	≤0.016	0.125
	Piperacillin-tazobactam	≤0.125-0.5	≤0.125	0.5
	Amoxicillin-clavulanate	≤0.125-0.5	≤0.125	0.25
	Ceftriaxone	≤0.125	≤0.125	≤0.125
	Clindamycin	0.03-0.125	0.06	0.125
	Metronidazole	≤0.125-0.5	≤0.125	0.5
Fusobacterium varium (0/10)	Doripenem	0.06-1	0.125	0.25
	Imipenem	0.5-2	1	1
	Meropenem	0.06-0.25	0.125	0.25
	Ertapenem	0.06-0.125	0.06	0.125
	Piperacillin-tazobactam	2-32	8	8
	Amoxicillin-clavulanate	1-4	2	4
	Ceftriaxone	≤0.125-8	4	8
	Clindamycin	2->16	4	16
	Metronidazole	≤0.125-0.5	0.25	0.5
Fusobacterium mortiferum (2/10)	Doripenem	0.125-1	0.25	1
	Imipenem	0.25-1	1	1
	Meropenem	0.06-1	0.125	0.5
	Ertapenem	0.06-0.5	0.06	0.5
	Piperacillin-tazobactam	≤0.125-4	0.25	2
	Amoxicillin-clavulanate	0.5-32	1	16
	Ceftriaxone	≤0.125->128	128	≥128
	Clindamycin	0.06-8	0.06	0.25
	Metronidazole	≤0.125	≤0.125	≤0.125
Finegoldia magna (0/10)	Doripenem	0.06-0.125	0.06	0.125
	Imipenem	0.03-0.06	0.06	0.06
	Meropenem	0.06-0.125	0.06	0.125
	Ertapenem	0.03-0.06	0.06	0.06
	Piperacillin-tazobactam	≤0.125-0.25	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-0.5	0.25	0.25
	Ceftriaxone	1-8	8	8
	Clindamycin	0.125->16	2	>16
	Metronidazole	0.25-1	0.5	1
Micromonas micros (0/10)	Doripenem	≤0.016-0.125	≤0.016	0.06
	Imipenem	0.03-0.125	0.03	0.06
	Meropenem	0.03-0.25	0.03	0.25
	Ertapenem	≤0.016-0.25	0.03	0.125
	Piperacillin-tazobactam	≤0.125	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125-1	≤0.125	0.5
	Ceftriaxone	≤0.125-2	≤0.125	1
	Clindamycin	0.125-0.5	0.25	0.5
	Metronidazole	≤0.125-0.5	0.25	0.5
Peptostreptococcus anaerobius (0/10)	Doripenem	0.125-2	0.25	2
	Imipenem	0.06-2	0.06	1
	Meropenem	0.25-2	0.25	2
	Ertapenem	0.25-2	0.5	2
	Piperacillin-tazobactam	0.25-16	0.25	16
	Amoxicillin-clavulanate	0.25-32	0.5	32
	Ceftriaxone	0.5-16	0.5	16
	Clindamycin	0.03-0.5	0.03	0.25
	Metronidazole	≤0.125-1	0.5	1
Anaerococcus prevotii (0/4)	Doripenem	0.03
	Imipenem	≤0.016-0.03
	Meropenem	≤0.016-0.03
	Ertapenem	≤0.016-0.125
	Piperacillin-tazobactam	≤0.125
	Amoxicillin-clavulanate	≤0.125
	Ceftriaxone	≤0.125-0.5
	Clindamycin	0.125-0.5
	Metronidazole	0.25-2
Anaerococcus tetradius (0/6)	Doripenem	≤0.016-0.06	0.03
	Imipenem	≤0.016-0.03	0.03
	Meropenem	0.03-0.06	0.03
	Ertapenem	0.06-0.125	0.06
	Piperacillin-tazobactam	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125	≤0.125
	Ceftriaxone	0.25-0.5	0.25
	Clindamycin	0.5-1	0.5
	Metronidazole	1-4	2
Peptoniphilus asaccharolyticus (0/10)	Doripenem	≤0.016-0.125	≤0.016	0.03
	Imipenem	≤0.016-0.06	≤0.016	0.03
	Meropenem	≤0.016-0.125	≤0.016	0.03
	Ertapenem	≤0.016-0.5	≤0.016	0.06
	Piperacillin-tazobactam	≤0.125-0.25	≤0.125	≤0.125
	Amoxicillin-clavulanate	≤0.125	≤0.125	≤0.125
	Ceftriaxone	≤0.125-1	≤0.125	1
	Clindamycin	0.06->16	0.06	>16
	Metronidazole	≤0.125-2	1	1
Clostridium perfringens (0/30)	Doripenem	≤0.016-0.06	0.03	0.03
	Imipenem	≤0.016-0.125	0.06	0.125
	Meropenem	≤0.016-0.03	≤0.016	≤0.016
	Ertapenem	≤0.016-0.125	0.06	0.125
	Piperacillin-tazobactam	≤0.125-1	0.25	0.5
	Amoxicillin-clavulanate	≤0.125	≤0.125	≤0.125
	Ceftriaxone	≤0.125-4	2	4
	Clindamycin	0.06-4	1	2
	Metronidazole	0.5-2	1	2
Clostridium difficile (0/20)	Doripenem	1-4	2	4
	Imipenem	4-8	8	8
	Meropenem	1-4	2	4
	Ertapenem	4-8	4	8
	Piperacillin-tazobactam	8-32	16	32
	Amoxicillin-clavulanate	1-2	1	2
	Ceftriaxone	32-128	64	64
	Clindamycin	4->16	8	>16
	Metronidazole	0.25-1	0.5	0.5
Clostridium innocuum (0/6)	Doripenem	1	1
	Imipenem	1-2	1
	Meropenem	1-2	2
	Ertapenem	2-4	2
	Piperacillin-tazobactam	1-2	1
	Amoxicillin-clavulanate	0.25-0.5	0.5
	Ceftriaxone	8-16	16
	Clindamycin	0.5-2	1
	Metronidazole	0.5-1	1
Clostridium ramosum (0/5)	Doripenem	0.5-1	0.5
	Imipenem	0.25-0.5	0.25
	Meropenem	0.5-2	1
	Ertapenem	1-2	1
	Piperacillin-tazobactam	≤0.125-0.25	0.25
	Amoxicillin-clavulanate	≤0.125	≤0.125
	Ceftriaxone	0.25-0.5	0.5
	Clindamycin	2-8	4
	Metronidazole	0.5-2	2
Clostridium bifermentans (0/4)	Doripenem	0.06-0.125
	Imipenem	0.25-0.5
	Meropenem	0.125
	Ertapenem	0.125
	Piperacillin-tazobactam	0.5-1
	Amoxicillin-clavulanate	0.25-2
	Ceftriaxone	0.25
	Clindamycin	0.06-0.25
	Metronidazole	0.25-0.5
Clostridium clostridioforme (0/2)	Doripenem	1
	Imipenem	2
	Meropenem	1
	Ertapenem	1-2
	Piperacillin-tazobactam	16
	Amoxicillin-clavulanate	1
	Ceftriaxone	64
	Clindamycin	0.06
	Metronidazole	≤0.125-0.25
Clostridium sordellii (0/2)	Doripenem	0.03
	Imipenem	0.125
	Meropenem	0.06
	Ertapenem	0.03
	Piperacillin-tazobactam	0.25
	Amoxicillin-clavulanate	≤0.125
	Ceftriaxone	≤0.125-0.25
	Clindamycin	1
	Metronidazole	0.5-1
Clostridium paraputrificum (0/1)	Doripenem	0.25
	Imipenem	0.5
	Meropenem	0.25
	Ertapenem	0.125
	Piperacillin-tazobactam	0.25
	Amoxicillin-clavulanate	0.5
	Ceftriaxone	4
	Clindamycin	8
	Metronidazole	0.5
Clostridium cadaveris (0/1)	Doripenem	0.03
	Imipenem	0.125
	Meropenem	0.03
	Ertapenem	≤0.016
	Piperacillin-tazobactam	0.5
	Amoxicillin-clavulanate	≤0.125
	Ceftriaxone	4
	Clindamycin	0.03
	Metronidazole	0.25

^aThe numbers of β-lactamase-positive strains/numbers of strains tested are indicated in parentheses.