In vitro susceptibility of Escherichia colistrains isolated from urine samples obtained in mainland China to fosfomycin trometamol and other antibiotics: a 9-year surveillance study (2004–2012)

Table 1 Comparison of antimicrobial susceptibilities between 2004 and 2012

Antibiotic^a	10/2004–9/2005 (n = 168)		1/2007–12/2007 (n = 271)		7/2009–6/2010 (n = 262)		7/2011–6/2012 (n = 207)		p
	S (%)	MIC₉₀(mg/L)	S (%)	MIC₉₀(mg/L)	S (%)	MIC₉₀(mg/L)	S (%)	MIC₉₀(mg/L)
FOS	99.4	2	95.9	1	95.0	4	93.2*	8	0.030
TZP	94.0	16	97.8	8	92.7	16	94.7	8	0.058
CXM	42.3	512	32.8	512	27.5*	512	30.9	512	0.015
CTX	53.0	128	37.6*	256	30.9*	512	36.2*	512	< 0.001
FEP	88.1	16	76.4*	32	61.5^,*	64	75.4^,**	32	< 0.001
IMP	100	0.25	99.6	0.25	99.6	0.125	99.5	0.125	1.000
AMK	94.6	4	95.6	4	92.7	8	93.2	4	0.519
NIT	78.6	64	83.0	64	91.6^,*	32	88.9*	64	< 0.001
LVX	31.0	32	28.0	32	28.2	32	32.4	32	0.693

^aDrug abbreviations: FOS, fosfomycin trometamol; TZP, piperacillin-tazobactam; CXM, cefuroxime; CTX, cefotaxime; FEP, cefepime; IMP, imipenem; AMK, amikacin; NIT, nitrofurantoin; LVX, levofloxacin.
*compared to 10/2004–9/2005, p < 0.0083.
**compared to 1/2007–12/2007, p < 0.0083.
***compared to 7/2009–6/2010, p < 0.0083.

ISSN: 1471-2334