Table 2.

Susceptibilities of planktonic and biofilms of carbapenemase-producing K. pneumoniae clinical isolates (n = 29) to Ca-EDTA, Aztreonam and Ceftazidime/Avibactam and their combination in vitro

No of isolates	Gene pattern	Pattern of entire of bla gene by sequencing	Biofilm formation category	ATM (μg/mL)	CZA (μg/mL)	CaEDTA (mg/mL)	ATM +CZA(μg/mL)	ATM (μg/mL) +CaEDTA (mg/mL)	CZA (μg/mL) +CaEDTA (mg/mL)	ATM (μg/mL)	CZA(μg/mL)	CaEDTA	ATM + CZA (μg/mL)	ATM (μg/mL) +CaEDTA (mg/mL)	CZA (μg/mL) + CaEDTA (mg/mL)
5	IMP	IMP-14a	Strong	512–128	256–64	24–6	8–0.5/8–0.5	32/0.75–0.375	0.5/0.375	2048–1024	4096	6	4/8	2/3	2/6
5	NDM	NDM-1	Moderate	512–128	128–64	12–6	8–0.5/2–0.5	32/0.75	0.5/0.375	2048	4096	6	4/8	2/3	2/6
4			Strong	512–128	256–64	24–6	8–0.5/8–0.5	32/0.75	0.5/0.375	2048–1024	4096	12	4/8	2/3	2/6
1	OXA-48	OXA-181	Moderate	128	128	12	0.5/8	32/0.75–0.375	0.5/0.375	2048	4096	24	4/8	2/3	2/6
1	OXA-48+NDM	OXA-181+NDM-5	Strong	128	128	6	8/0.5	32/0.375	0.5/0.375	2048	4096	6	4/8	2/3	2/6
3	OXA-48	OXA-232	Strong	512–128	256–64	12–6	8–0.5/8–0.5	32/0.75	0.5/0.375	2048	4096	6	4/8	2/3	2/6
3	OXA-48+NDM	OXA-232+NDM-1	Moderate	512–256	256–128	12–6	8–0.5/8–0.5	32/0.75	0.5/0.375	2048	4096	6	4/8	2/3	2/6
5			Strong	512–128	256–64	12–6	8–0.5/8–0.5	32/0.75–0.375	0.5/0.375	2048–1024	4096	6	4/8	2/3	2/6
1	OXA-48	OXA-48	Moderate	128	128	6	2/0.5	32/0.75–0.375	0.5/0.375	2048	4096	6	4/8	2/3	2/6
1			Strong	128	128	6	0.5/8	32/0.375	0.5/0.375	2048	4096	12	4/8	2/3	2/6

ATM Aztreonam.

CZA Ceftazidime/Avibactam.

Calcium disodium ethylenediaminetetraacetate (Ca-EDTA).

Minimal inhibitory concentrations (MIC, μgmL⁻¹) for planktonic cells.

Minimal biofilm eradication concentrations (MBEC, μgmL⁻¹) for mature biofilms.