TABLE 4.

Clinical and microbiologic characteristics of patients in whom ceftazidime-avibactam resistance developed

Pta	Age (sex)b	Underlying diseasec	CRE pathogend	Type of initial infection	Baseline creatinine clearance (ml/min)e	Initial treatmentf (days)	Clinical outcome at 30 days	Time to microbiologic failure (days)	Causes of microbiologic failure and outcome at 90 days	C-A MIC (μg/ml) for:		KPC-3 variant of posttreatment isolate
										Pretreatment isolate	Posttreatment isolate
1	49 (F)	Double lung transplant	ST258, KPC-3-producing CRKP	Pneumonia	51	C-A, 2.5 g i.v. q8h (10)	Failure	14	Reinfection: pneumonia, treated with C-A for an additional 14 days	2	1) 32	1) D179Y T243M
											2) 256g	2) D179Y T243M
								28	Persistent pneumonia, treated with meropenem and gentamicin until death	Not applicable	256	D179Y T243M
2	58 (F)	Morbid obesity s/p gastric sleeve surgery	ST258, KPC-3-producing CRKP	Intra-abdominal infection	CRRT	C-A, 0.94 g i.v. q12h (19)	Failure	41	Urine colonization, not treated and survived	4	1) 32	1) V240G
											2) >256g	2) D179Y
3	73 (M)	Esophageal cancer s/p esophagectomy	ST258, KPC-3-producing CRKP	Pneumonia	113	C-A, 2.5 g i.v. q8h (15)	Success	34	Respiratory colonization, not treated	2	2	Wild type
								58	Respiratory colonization, not treated	Not applicable	1) 64	1) D179Y
											2) 128g	2) D179Y
								76	Recurrent pneumonia, treated with meropenem and colistin for 14 days and survived	Not applicable	1) 2	1) Wild type
											2) 64g	2) D179Y
4	67 (M)	Esophageal cancer s/p esophagectomy	ST258, KPC-3-producing CRKP	Pneumonia	CRRT	C-A, 1.25 g i.v. q8h (15); inhaled gentamicin (15)	Failure	25	Relapsing intra-abdominal infection, treated with C-A for an additional 15 days	1	256	A177E D179Y
								72	Relapsing bacteremia, treated with meropenem for 14 days and survived	Not applicable	128	A177E D179Y
5	43 (F)	Double lung transplant	ST258, KPC-3-producing CRKP	Pneumonia	iHD	C-A, 0.94 g i.v. q48h (11)	Failure	74	Relapsing pneumonia, treated with C-A for 4 additional days prior to death	2	64	D179Y
6	59 (M)	Coronary artery disease, diabetes mellitus	ST258, KPC-3-producing CRKP	Pneumonia	47	C-A, 2.5 g i.v. q8h (11)	Failure	7	Persistent pneumonia, treated with doripenem and gentamicin for 14 days	2	64	D179Y
								26	Respiratory colonization, not treated and survived	Not applicable	1) 4	1) Wild type
											2) 32g	2) D179Y
7	60 (F)	Double lung transplant	ST258, KPC-3-producing CRKP	Pneumonia	iHD	C-A, 0.94 g i.v. q48h (7)	Failure	7	Breakthrough bacteremia, treated with C-A for an additional 18 days	4	1	Wild type
								101	Respiratory colonization, not treated and survived	Not applicable	64	166–167 EL ins
8	68 (M)	Double lung transplant	ST258, KPC-3-producing CRKP	Pneumonia	CRRT	C-A, 2.5 g i.v. q8h (14); i.v. and inhaled gentamicin (12)	Failure	33	Respiratory colonization, not treated	2	1) 2	1) Wild type
											2) 4g	2) Wild type
								42	Relapsing tracheobronchitis, treated with C-A and inhaled gentamicin for 17 days	Not applicable	2	Wild type
								61	Persistent tracheobronchitis, treated with meropenem and gentamicin for 11 days until death	Not applicable	64	D179Y

^aPt, patient.

^bM, male; F, female.

^cs/p, status post.

^dCRE, carbapenem-resistant Enterobacteriaceae; CRKP, carbapenem-resistant K. pneumoniae.

^eCRRT, continuous renal replacement therapy; iHD, intermittent hemodialysis.

^fC-A, ceftazidime-avibactam; q8h, every 8 h.

^gTwo morphologies isolated from the same biologic specimen.