TABLE 1.

STs, β-lactamase genes, and antibiotic resistance profiles of the study sample

Strain	Genomic analysis result			MIC (mg/L) fora:		MHA test resultb		MIC or MBC (geometric mean) in:				PAP result
								CAMHB	ID-CAMHB
	ST	bla OXA	bla ADC	MEM	COL	DD diameter (mm)	S/HR/NSc	MIC (mg/L)	MIC (mg/L)	MBC (mg/L)	MBC/MIC	2 mg/L of FDC/antibiotic-free CFU/mL proportion (%)	32 mg/L of FDC/antibiotic-free CFU/mL ratio	S/HR/NSd
Abau1	2	OXA23,116	ADC25	64 (R)	1 (S)	12	NS	4	8	16	2	>50	>1/106	HR
Abau2	2	OXA23,66	ADC25	64 (R)	2 (S)	24	S	1	0.5	2	4	<50	>1/106	HR
Abau3	2	OXA23,116	ADC25	64 (R)	>64 (R)	17	S	1	4	8	2	>50	>1/106	HR
Abau4	52	OXA66,72	ADC25	>64 (R)	8 (R)	16	NS	8	1	2	2	>50	>1/106	HR
Abau5	2	OXA23,82	ADC25	>64 (R)	2 (S)	15 i.c.	NS/HR	4	4	4	1	>50e	>1/106	NS
Abau6	2	OXA23,82	ADC25	>64 (R)	1 (S)	15 i.c.	NS/HR	8	4	4	1	>50	>1/106	HR
Abau7	2	OXA23,82	ADC25	>64 (R)	2 (S)	15	NS	8	16	32	2	>50	>1/106	HR
ACICU	2	OXA20,66	ADC25	64 (R)	1 (S)	17	S	8	2	8	4	>50	>1/106	HR
ATCC 19606	52	OXA98	ADC25	0.5 (S)	1 (S)	26	S	0.12	0.06	0.5	8	<50e	>1/106	HR
ATCC 17978	77	OXA95	ADC25	1 (S)	1 (S)	22	S	0.25	0.06	0.25	4	<50e	<1/106	S

^aMEM, meropenem; COL, colistin; S, susceptible; R, resistant.

^bHR, heteroresistant; NS, nonsusceptible; i.c., colonies within the zone of clearing.

^cCharacterized as susceptible or nonsusceptible in accordance with the EUCAST breakpoints for FDC and AST. A zone diameter of ≥17 mm is typical for isolates with MIC values of ≤2 mg/L (Enterobacterales, Pseudomonas aeruginosa, and the pharmacokinetic/pharmacodynamic breakpoint) (19); the presence of colonies within a zone of clearing indicates a possible heteroresistance phenotype (14).

^dCharacterized as susceptible, heteroresistant, or nonsusceptible following the published protocol (6, 26).

^eP ≤ 0.05 (Student's t test).