TABLE 3.

Acquired β-lactamase genes identified in meropenem-resistant P. aeruginosa isolates (n = 139)^a,b

Isolate	β-Lactamase group						Total
	MBL	MBL + KPC	MBL + ESBL	MBL + OXA	ESBL	Negative
P. aeruginosa	27	1	1	1	8	101	139

^a ESBL, extended-spectrum β-lactamase; KPC, Klebsiella pneumoniae carbapenemase; MBL, metallo-β-lactamase; OXA, oxacillinase; PCR, polymerase chain reaction; WGS, whole-genome sequencing.

^b Data were generated by WGS if meropenem-resistant isolates were resistant to cefiderocol (4/139) or PCR if isolates were susceptible to cefiderocol (135/139). Isolates are grouped as “negative” if only intrinsic β-lactamase genes were present.