. 2008 Aug 15;190(20):6779–6794. doi: 10.1128/JB.00661-08

TABLE 1.

Resistance levels of E. coli SMS-3-5

Antibiotic	MIC (μg/ml)	CLSI MIC breakpoint (μg/ml)
β-Lactams
Amoxicillin	>5,000	ND^a
Ampicillin	>2,500	≥32^b
Cefoxitin	64	≥32^b
Ceftriaxone	32	≥64^b
Cephalexin	200	ND^a
Cephalothin	64	≥32^b
Imipenem	2	≥16^b
Meropenem	2	≥16^b
Penicillin	250	ND^a
Piperacillin	>10,000	≥128^b
Aminoglycosides
Amikacin	8	≥64^b
Apramycin	8	ND^a
Gentamicin	2	≥16^b
Kanamycin	>2,500	≥64^b
Streptomycin	>5,000	ND^a
Quinolones
Ciprofloxacin	200	≥4^b
Levofloxacin	125	≥8^b
Moxifloxacin	45	ND^a
Nalidixic acid	>1,000	≥32^b
Norfloxacin	>500	≥16^b
Ofloxacin	>1,000	≥8^b
Sparfloxacin	125	ND^a
Macrolides
Azithromycin	2	ND^a
Erythromycin	16	ND^a
Rifampin	25	ND^a
Sulfonamides
Sulfathiazole	>5,000	≥512^b
Trimethoprim	>500	≥16^b
Trimethoprim/Sulfamethoxazole	>500	≥4/76^b
Tetracyclines
Doxycycline	60	≥16^b
Oxytetracycline	250	ND^a
Tetracycline	>512	≥16^b
Miscellaneous
Chlorampenicol	256	≥32^b
Nitrofurantoin	<16	≥128^b

No current susceptibility guidelines according to NCCLS/CLSI (56a) are available.

Agent for which established antimicrobial resistance guidelines are currently available according to NCCLS/CLSI interpretive criteria for broth microdilution (56a).