Analysis of In Vitro Activity of Cefiderocol Against Carbapenem-Resistant Gram-Negative Bacilli by Broth Microdilution and Disk Diffusion Method: A Single-Center Study in Odisha, India

Figures & data

Table 1 Sample-Wise Distribution of Different Genera of Carbapenem-Resistant GNB (CR-GNB)(n=503)

Specimen	E. coli (n = 183)	K. pneumoniae (n = 152)	E. cloacae Complex (n = 7)	A.baumannii Complex (n = 137)	P. aeruginosa (n = 24)
Blood (n = 170)	39	68	5	57	1
Urine (n = 124)	89	16	0	12	7
Respiratory (n = 123)	26	39	1	51	6
Pus and exudates (n = 54)	17	18	1	9	9
Fluid from sterile body sites (n = 32)	12	11	0	8	1

Abbreviation: n, Total number of isolates tested.

Table 2 CFDC MIC Distribution Against Different Genera of CR-GNB (n=503)

	CFDC MIC in μg/mL
CR-GNB Genera	<0.25	0.25	0.5	1	2	4	8	16	32	64	128	>128	Range	MIC50	MIC 90
E. coli (n = 183)	18	0	19	25	65	17	16	4	6	2	4	7	<0.25->128	2	32
K. pneumoniae (n = 152)	4	5	30	27	36	26	14	6	1	0	0	3	<0.25->128	2	8
A. baumannii complex (n = 137)	5	6	19	20	19	43	17	2	0	0	0	6	<0.25->128	2	8
P. aeruginosa (n = 24)	1	2	6	5	5	2	1	1	1	0	0	0	<0.25–32	1	8
E. cloacae complex (n = 7)	0	0	1	1	3	1	0	0	1	0	0	0	0.5–32	2	32
Total	28	13	75	78	128	89	48	13	9	2	4	16

Abbreviations: MIC, Minimum inhibitory concentration; MIC₅₀, Minimum inhibitory concentration (MIC)50; MIC₉₀, Minimum inhibitory concentration (MIC)90; n, Total number of isolates tested.

Figure 1 Distribution of CFDC MICs to zone diameters (A) for Enterobacterales, (B) for A. baumannii complex, (C), for P. aeruginosa). BMD MICs (µg/mL) are on the X axis, and zone diameters in (mm) are on the Y axis. The isolates highlighted in Green are in Categorical agreement (CA) by both the methods. Isolates showing VME are highlighted in red and ME are highlighted in brown color. Areas highlighted with grey contain isolates of Intermediate Category Isolates above (For BMD) and left (For DD) to Red bar are RESISTANT isolates. Isolates below (For BMD) and right (For DD) to Green bar are SUSCEPTIBLE isolates.

Table 3 Agreement and Error Rates of DD, Taking BMD as the Reference Method

Organisms	No. of Isolates	CA [no.(%)]	mE [no.(%)]	ME [no. (%)]	VME [no.(%)]
Enterobacterales	342	280(81.9)	43(12.6)	6(2.2)	3(8.8)
E. coli	183	146(79.8)	25(13.6)	5(3.5)	1(4.3)
K. pneumoniae	152	128(84.2)	18(11.8)	1(0.8)	1(10)
E.cloacae complex	7	6(85.7)	0(0)	0(0)	1(100)
Non-glucose-fermenting GNB	161	138(85.7)	20(12.4)	0(0)	1(10)
A. baumannii complex	137	117 (85.4)	18(13.1)	0(0)	1(12.5)
P. aeruginosa	24	21(87.5)	2(8.3)	0(0)	0(0)
Total	503	418(83.1)	63(12.5)	6(1.45)	4(9.1)

Abbreviations: CA, Categorical agreement; mE, Minor error; ME, Major error; VME, Very Major error.

Table 4 Distribution of MIC Across Different Carbapenemase Genes and Specific Groups of CR-GNB (n=319)

	Cefiderocol MIC											%Susceptible		MIC Values (µg/mL)
Enterobacterales (n=201)	>128	128	64	32	16	8	4	2	1	0.5	0.25	<0.25	% (No.)	MIC50	MIC90	Total
Carbapenemase-producing –CRE													72.6(138)	2	16	190
Non-Carbapenemase producing –CRE													54.5(6)	2	>128	11
MIC by type of carbapenemase in CRE
NDM-1	5	2	2	3	5	13	15	31	10	7	2	1	68.7(66)			96
NDM-1 and OXA48-like allele	1	1	0	2	3	10	15	25	6	3	1	0	74.6(50)			67
OXA 48-like allele	0	0	0	0	0	5	5	9	6	2	0	0	81.5(22)			27
No genes detected	2	1	0	1	0	1	1	1	1	2	0	1	54.5(6)			11
Non-glucose fermenting GNB (n=118)
Carbapenemase-producing – NFGNB													82.6(38)	2	8	46
Non-Carbapenemase producing – NFGNB													73.6(53)	4	16	72
MIC by type of carbapenemase in CR-NFGNB
Acinetobacter baumannii complex
NDM-1	0	0	0	0	0	4	8	6	3	6	1	0	85.7(24)			28
NDM-1 and OXA48-like allele	0	0	0	0	0	2	2	4	0	0	0	0	75(6)			8
OXA 48-like allele	0	0	0	0	0	0	0	0	0	0	1	0	100(1)			1
No genes detected	6	0	0	0	2	11	27	6	8	2	3	1	71.2(47)			66
P. aeruginosa
NDM-1	0	0	0	0	1	1	0	2	2	1	1	0	75(6)			8
NDM-1 and OXA48-like allele	0	0	0	0	0	0	0	1	0	0	0	0	100(1)			1
OXA 48 like allele	0	0	0	0	0	0	0	0	0	0	0	0	0(0)			0
No genes detected	0	0	0	0	0	0	2	1	0	2	1	0	100(6)			6

Abbreviations: CRE, Carbapenem-resistant Enterobacterales; NFGNB, Non-glucose fermenting GNB; NDM, New Delhi-metallo β-lactamases; OXA 48, Oxacillinases 48.