Table 2.

Antimicrobial activity of ceftazidime-avibactam and comparators against Pseudomonas aeruginosa isolates collected from Croatia, Czech Republic, Hungary, Poland, Latvia and Lithuania in 2019

Antimicrobial	MIC90 (mg/L)	Range (mg/L)	Susceptible, standard dosing		Susceptible, increased exposure		Resistant
P. aeruginosa (n = 701)			n	%	n	%	n	%
Amikacin	32	0.5 – ≥ 128	625	89.2	–	–	76	10.8
Aztreonam	32	0.25 – ≥ 256	–	–	586	83.6	115	16.4
Cefepime	32	0.5 – ≥ 64	–	–	539	76.9	162	23.1
Ceftazidime	64	0.25 – ≥ 256	–	–	521	74.3	180	25.7
Ceftazidime-avibactam	8	0.12 – ≥ 256	646	92.2	–	–	55	7.8
Ciprofloxacin	≥ 8	≤ 0.12 – ≥ 8	–	–	477	68.0	224	32.0
Colistin	2	0.25 – ≥ 16	700	99.9	–	–	1	0.1
Gentamicin	≥ 32	≤ 0.12 – ≥ 32	–	–	–	–	–	–
Imipenem	≥ 16	≤ 0.06 – ≥ 16	–	–	473	67.5	228	32.5
Levofloxacin	≥ 16	≤ 0.25 – ≥ 16	–	–	437	62.3	264	37.7
Meropenem	16	≤ 0.06 – ≥ 32	471	67.2	105	15.0	125	17.8
Piperacillin-tazobactam	≥ 128	≤ 0.12 – ≥ 128	–	–	501	71.5	200	28.5
Tigecycline	≥ 16	1 – ≥ 16	–	–	–	–	–	–
DTR P. aeruginosa (n = 40)
Amikacin	64	2 – ≥ 128	25	62.5	–	–	15	37.5
Aztreonam	64	32 – ≥ 256	–	–	0	0.0	40	100
Cefepime	≥ 64	16 – ≥ 64	–	–	0	0.0	40	100
Ceftazidime	≥ 256	16 – ≥ 256	–	–	0	0.0	40	100
Ceftazidime-avibactam	≥ 256	4 – ≥ 256	15	37.5	–	–	25	62.5
Ciprofloxacin	≥ 8	1 – ≥ 8	–	–	0	0.0	40	100
Colistin	2	0.5 – 2	40	100	–	–	0	0.0
Gentamicin	≥ 32	0.25 – ≥ 32	–	–	–	–	–	–
Imipenem	≥ 16	8 – ≥ 16	–	–	0	0.0	40	100
Levofloxacin	≥ 16	4 – ≥ 16	–	–	0	0.0	40	100
Meropenem	≥ 32	16 – ≥ 32	0	0.0	0	0.0	40	100
Piperacillin-tazobactam	≥ 128	32 – ≥ 128	–	–	0	0.0	40	100
Tigecycline	≥ 16	1 – ≥ 16	–	–	–	–	–	–
MDR P. aeruginosa (n = 199)
Amikacin	≥ 128	0.5 – ≥ 128	136	68.3	–	–	63	31.7
Aztreonam	64	4 – ≥ 256	–	–	88	44.2	111	55.8
Cefepime	≥ 64	2 – ≥ 64	–	–	45	22.6	154	77.4
Ceftazidime	≥ 256	2 – ≥ 256	–	–	32	16.1	167	83.9
Ceftazidime-avibactam	64	1 – ≥ 256	145	72.9	–	–	54	27.1
Ciprofloxacin	≥ 8	≤ 0.12 – ≥ 8	–	–	51	25.6	148	74.4
Colistin	2	0.25 – ≥ 16	198	99.5	–	–	1	0.5
Gentamicin	≥ 32	≤ 0.12 – ≥ 32	–	–	–	–	–	–
Imipenem	≥ 16	0.5 – ≥ 16	–	–	54	27.1	145	72.9
Levofloxacin	≥ 16	≤ 0.25 – ≥ 16	–	–	38	19.1	161	80.9
Meropenem	≥ 32	≤ 0.06 – ≥ 32	40	20.1	46	23.1	113	56.8
Piperacillin-tazobactam	≥ 128	8 – ≥ 128	–	–	20	10.1	179	89.9
Tigecycline	≥ 16	1 – ≥ 16	–	–	–	–	–	–
MEM-R P. aeruginosa (n = 125)
Amikacin	≥ 128	1 – ≥ 128	82	65.6	–	–	43	34.4
Aztreonam	64	4 – ≥ 256	–	–	68	54.4	57	45.6
Cefepime	≥ 64	2 – ≥ 64	–	–	39	31.2	86	68.8
Ceftazidime	≥ 256	2 – ≥ 256	–	–	30	24.0	95.0	76.0
Ceftazidime-avibactam	64	2 – ≥ 256	82	65.6	–	–	43	34.4
Ciprofloxacin	≥ 8	≤ 0.12 – ≥ 8	–	–	23	18.4	102	81.6
Colistin	2	0.25 – 2	125	100	–	–	0	0.0
Gentamicin	≥ 32	0.25 – ≥ 32	–	–	–	–	–	–
Imipenem	≥ 16	1 – ≥ 16	–	–	2	1.6	123	98.4
Levofloxacin	≥ 16	0.5 – ≥ 16	–	–	11	8.8	114	91.2
Piperacillin-tazobactam	≥ 128	4 – ≥ 128	–	–	23	18.4	102	81.6
Tigecycline	≥ 16	1 – ≥ 16	–	–	–	–	–	–
MEM-R, MBL-negative P. aeruginosa (n = 103)
Amikacin	64	1 – ≥ 128	75	72.8	–	–	28	27.2
Aztreonam	64	4 – ≥ 256	–	–	55	53.4	48	46.6
Cefepime	32	2 – ≥ 64	–	–	37	35.9	66	64.1
Ceftazidime	128	2 – ≥ 256	–	–	30	29.1	73	70.9
Ceftazidime-avibactam	16	2 – ≥ 256	81	78.6	–	–	22	21.4
Ciprofloxacin	≥ 8	≤ 0.12 – ≥ 8	–	–	18	17.5	85	82.5
Colistin	2	0.25 – 2	103	100	–	–	0	0.0
Gentamicin	≥ 32	0.25 – ≥ 32	–	–	–	–	–	–
Imipenem	≥ 16	1 – ≥ 16	–	–	2	1.9	101	98.1
Levofloxacin	≥ 16	0.5 – ≥ 16	–	–	8	7.8	95	92.2
Piperacillin-tazobactam	≥ 128	4 – ≥ 128	–	–	22	21.4	81	78.6
Tigecycline	≥ 16	1 – ≥ 16	–	–	–	–	–	–

MIC, minimum inhibitory concentration; DTR, difficult to treat; MDR, multidrug resistant; MEM-R, meropenem resistant; MBL, metallo-β-lactamase