Antimicrobial susceptibility testing in predicting the presence of carbapenemase genes in Enterobacteriaceae in South Africa

Table 1 Minimal inhibitory concentrations (MIC) of ertapenem susceptible carbapenemase producing isolates

Sample ID	ORGANISM	NDM	KPC	OXA-48 & variants	IMP	VIM	GES	Cefepime MIC	Cefotaxime MIC	Ceftazidime MIC	Ertapenem MIC	Imipenem MIC	Meropenem MIC	Doripenem MIC
ML0148.2	Enterobacter cloacae	-	-	-	+	-	-	>16	>32	>16	<=0.5	<=2	<=1	Not tested
ML0191	Klebsiella pneumoniae	-	-	-	-	-	+	8	>32	>16	<=0.5	<=2	<=1	Not tested
ML0440	Klebsiella pneumoniae	-	-	-	-	+	-	16	>32	>16	<=0.5	4	2	Not tested
ML0446	Klebsiella pneumoniae	-	-	-	-	+	-	<=1	<=1	<=1	<=0.5	<=2	<=1	Not tested
ML0848	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	4	<=1	<=1
ML0917	Providencia rettgeri	+	-	-	-	-	-	<=1	<=1	<=1	<=0.5	<=1	<=1	<=1
ML0926	Escherichia coli	+	-	-	-	-	-	<=1	<=1	<=1	<=0.5	<=1	<=1	<=1
ML0930	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	4	<=1	<=1
ML1002	Providencia rettgeri	+	-	-	-	-	-	8	32	>16	<=0.5	>8	2	2
ML1007	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	4	<=1	2
ML1161	Klebsiella pneumoniae	-	-	+	-	-	-	>16	>32	>16	<=0.5	<=2	<=1	Not tested
ML1187	Escherichia coli	-	-	+	-	+	-	2	8	16	<=0.5	4	<=1	<=1
ML1189	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	2	<=1	<=1
ML1219	Klebsiella pneumoniae	-	-	-	-	+	-	16	>32	>16	<=0.5	2	<=1	<=1
ML1279	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	2	<=1	<=1
ML1296	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	4	<=1	<=1
ML1340	Morganella morganii	+	-	-	-	-	-	8	>32	>16	<=0.5	8	<=1	2
ML1354	Klebsiella pneumoniae	-	-	-	-	+	-	>16	>32	>16	<=0.5	4	<=1	2

CLSI breakpoints: Cefepime: <=2 – Susceptible, 4-8 – Susceptible-Dose Dependant, > = 16 – Resistant; Cefotaxime: <=1 - Susceptible, 2 – Intermediate, > = 4 – Resistant; Ceftazidime: <=4 - - Susceptible, 8 – Intermediate, > = 16 – Resistant; Ertapenem: <=0.5- Susceptible, 1 – Intermediate, > = 2 – Resistant; Imipenem/Meropenem/Doripenem: <=1 – Susceptible, 2 – Intermediate, > = 4 Resistant [34]