TABLE 1.

MIC distributions for carbapenemase-producing isolates and those with a combination of AmpC or ESBL and impermeability^a

Enzyme and characteristic of isolate(s) (nb [description])	Drug(s)	No. of isolates for which MIC (μg/ml) is:
		≤0.03	0.06	0.12	0.25	0.5	1	2	4	8	16	32	64	128	256	512
KPC (10 [7 K. pneumoniae + 3	Ceftazidime															10*
Enterobacter spp.])	Ceftazidime + NXL104			1		3	3			1		2
	Ceftazidime + clav											2	8*
	Aztreonam													10*
	Aztreonam + NXL104		2	3	2	1		1	1
	Piperacillin														10*
	Piperacillin + tazobactam												1		9*
	Imipenem									1	1	3	2	2	1*
	Meropenem										1	3	1	3	2*
	Ertapenem												3	2	5*
SME-1 (1 [S. marcescens])	Ceftazidime				1
	Ceftazidime + NXL104				1
	Ceftazidime + clav				1
	Aztreonam										1
	Aztreonam + NXL104				1
	Piperacillin												1
	Piperacillin + tazobactam								1
	Imipenem														1*
	Meropenem									1
	Ertapenem									1
OXA-48 (19 [all K. pneumoniae])	Ceftazidime			1**		8	2					1		2		5
	Ceftazidime + NXL104		1**	1	8	6	3
	Ceftazidime + clav					1	3	2	6	2	2		3*
	Aztreonam		1	2	7	1								2	6*
	Aztreonam + NXL104	1**	4	10	2	2
	Piperacillin														19*
	Piperacillin + tazobactam												1		18*
	Imipenem				1		1	2	4	2		2	3	2	2*
	Meropenem		1			1	2	2	3			5	1	4
	Ertapenem				1			1	1	5	1		3	3	4*
IMP (13 [7 K. pneumoniae, 5	Ceftazidime														1	12
Enterobacter spp. and 1	Ceftazidime + NXL104	1**														12
E. coli])	Ceftazidime + clav												13*
	Aztreonam			2	5	1				1					4*
	Aztreonam + NXL104		2	3	2	3		1	1
	Piperacillin											1		1	11*
	Piperacillin + tazobactam										1		1		11*
	Imipenem							1	1	2	7	1			1*
	Meropenem								2		2	8	1
	Ertapenem									2	2	8			1*
VIM (5 [4 K. pneumoniae and 1	Ceftazidime												1			4
Enterobacter sp.])	Ceftazidime + NXL104												1		1	3
	Ceftazidime + clav												5*
	Aztreonam				1		1							1	2*
	Aztreonam + NXL104			2	2	1
	Piperacillin														5*
	Piperacillin + tazobactam														5*
	Imipenem								1		2		2
	Meropenem						1		1			1		1	1*
	Ertapenem								2			2			1
NDM-1 (17 [6 K. pneumoniae, 6	Ceftazidime															17
E. coli, 2 Enterobacter spp., 2	Ceftazidime + NXL104															17
Citrobacter freundii and 1	Ceftazidime + clav												17*
Morganella morganii])	Aztreonam		1	1	1						1			2	11*
	Aztreonam + NXL104	2**	2	1	4	1	2	3	2
	Piperacillin														17*
	Piperacillin + tazobactam													1	16*
	Imipenem									1	1	8	3	2	2*
	Meropenem								1			7	3	3	3*
	Ertapenem								1			3	3	5	5*
Porin loss and AmpC (5 [all Enterobacter spp.])	Ceftazidime												1		4
	Ceftazidime + NXL104				1	1	3
	Ceftazidime + clav												5*
	Aztreonam												3	1	1*
	Aztreonam + NXL104				1	1	3
	Piperacillin												1	1	3*
	Piperacillin + tazobactam										1		2		2*
	Imipenem							1	1	3
	Meropenem							2	2	1
	Ertapenem									1	1	2	1
Porin loss and ESBL (10 [all K. pneumoniae])	Ceftazidime										1				4	5
	Ceftazidime + NXL104					2	7	1
	Ceftazidime + clav						1			2	1	1	4*
	Aztreonam												2		8*
	Aztreonam + NXL104		1		7	1	1
	Piperacillin														10*
	Piperacillin + tazobactam														10*
	Imipenem					1	2	5	2
	Meropenem				1				2	4		3
	Ertapenem						1			1		3	5

^aClav, clavulanate. *, MIC ≥ indicated value; **, MIC ≤ indicated value.

^bn, no. of isolates.