Molecular Epidemiology of Carbapenemase-Producing Pseudomonas aeruginosa Isolated from an Iranian University Hospital: Evidence for Spread of High-Risk Clones

Figures & data

Figure 1 Flow of sample collection and study design through the study and detection of carbapenemase-producing P. aeruginosa isolate.

Table 1 The Susceptibility of Carbapenem-Resistant P. Aeruginosa Isolates to the Different Antimicrobial Agents

Isolate N(%)	ST	No (%)	Selected Antimicrobial Agents
			Piperacillin N(%)	Ceftazidime N(%)	Cefepime N(%)	Aztreonam N(%)	Piperacillin/Tazobactam N(%)	Gentamicin N(%)	Tobramycin N(%)	Amikacin N(%)	Ciprofloxacin N(%)
CRPA 38 (55.88)	235	14 (37.0)	14 (100)	14 (100)	14 (100)	14 (100)	14 (100)	14 (100)	11 (78.5)	6 (42.8)	14 (100)
	357	8 (21.0)	8 (100)	8 (100)	8 (100)	8 (100)	8 (100)	8 (100)	5 (62.5)	5 (62.5)	8 (100)
	175	4 (10.5)	4 (100)	4 (100)	3 (75)	4 (100)	3 (75)	4 (100)	1 (25)	1 (25)	3 (75)
	111	4 (10.5)	4 (100)	4 (100)	4 (100)	4 (100)	4 (100)	4 (100)	1 (25)	1 (25)	4 (100)
	253	2 (5.3)	2 (100)	1 (50)	0	0	0	2 (100)	0	0	0
	360	2 (5.3)	0	0	0	0	0	2 (100)	0	0	0
	773	1 (2.6)	1 (100)	1 (100)	1 (100)	1 (100)	1 (100)	1 (100)	0	0	0
	207	1 (2.6)	0	1 (100)	1 (100)	0	0	1 (100)	0	0	0
	823	1 (2.6)	1 (100)	1 (100)	1 (100)	0	1 (100)	1 (100)	0	0	1 (100)
	861	1 (2.6)	1 (100)	1 (100)	1 (100)	1 (100)	1 (100)	1 (100)	0	0	1 (100)
Total N(%)			35 (92.1)	36 (92.1)	33 (86.8)	32 (84.2)	32 (84.2)	38 (100)	18 (47.3)	13 (34.2)	31 (81.5)
Non-CRPA 30 (44.12)	253	13 (43.3)	8 (61.5)	8 (61.5)	4 (30.7)	4 (30.7)	4 (30.7)	11 (84.6)	4 (30.7)	3 (23.0)	4 (30.7)
	360	9 (30.0)	0	0	0	0	0	6 (66.6)	0	0	0
	446	8 (26.7)	3 (33.3)	3 (33.3)	1 (12.5)	1 (12.5)	1 (12.5)	5 (62.5)	1 (12.5)	1 (12.5)	1 (12.5)
Total N(%)			11 (36.6)	11 (36.6)	5 (16.6)	5 (16.6)	5 (16.6)	22 (73.3)	5 (16.6)	4 (13.3)	5 (16.6)

Abbreviations: CRPA, carbapenem-resistant P. aeruginosa; CSPA, carbapenem-susceptible P. aeruginosa; ST, sequence type based on MLST analysis.

Table 2 MIC90 and MIC50 Values for Meropenem, Ceftazidime, and Cefepime Among CRPA and CSPS Isolates

Antimicrobial Agent				CRPA	CSPA
Meropenem	Resistance Breakpoint (µg/mL)		≥8
	Resistant N(%)			38(100)	0
	Range (µg/mL)	MIC50		8 to >32	–
		MIC90		8 to >32	–
Cefepime	Resistance Breakpoint (µg/mL)		≥32
	Resistant N(%)			33 (86.8)	5 (16.6)
	Range (µg/mL)	MIC50		16 to >1024	2–32
		MIC90		16 to >1024	2–32
Ceftazidime	Resistance Breakpoint (µg/mL)		≥32
	Resistant N(%)			36 (92.1)	11 (36.6)
	Range (µg/mL)	MIC50		32 to >1024	2–32
		MIC90		64 to >1024	2–32

Abbreviations: CRPA, carbapenem-resistant P. aeruginosa; CSPA, carbapenem-susceptible P. aeruginosa.

Figure 2 Genomic analysis of SpeI-digested DNA from P. aeruginosaisolates. Dendrogram based on the relationships among CRPA isolates derived from the UPGMA and Dice coefficients, using Gel ComparII software. Data about the results of MHT to identify carbapenemase activity, DDST for phenotypic detection of MBL activity, multiplex PCR assay for detection of MBL genes, and sequence type (ST) based on MLST analysis are presented, respectively.

Abbreviation: CRPA, carbapenem-resistant P. aeruginosa.