Double carbapenem as a rescue strategy for the treatment of severe carbapenemase-producing Klebsiella pneumoniae infections: a two-center, matched case–control study

Table 2 Therapeutic and microbiological details according to the type of treatment

Variable	Number (%) of patients		p value
Variable	DC group (n = 48)	ST group (n = 96)	p value
Polymicrobial infection	6 (12.5)	17 (17.7)	0.57
CR Acinetobacter baumannii	3 (6.25)	12 (12.5)	0.4
CR Pseudomonas aeruginosa	3 (6.25)	5 (5.2)	0.89
Combined targeted therapy	35 (72.9)	52 (54.2)	0.05
DC + colistin	19 (39.6)	–	–
DC + gentamicin	8 (16.9)	–	–
DC + tigecycline	3 (6.25)	–	–
DC + colistin + tigecycline	2 (4.2)	–	–
DC + colistin + gentamicin	3 (6.25)	–	–
Colistin + tigecycline	–	22 (22.9)	–
Colistin + gentamicin	–	13 (13.5)	–
Gentamicin + tigecycline	–	10 (10.4)	–
Colistin + tigecycline + gentamicin	–	7 (7.3)	–
Extensively drug-resistant strains^a	32 (66.7)	31 (32.3)	<0.01
Colistin MIC ≤ 2 μg/ml	28 (58.3)	64 (66.7)	0.42
Gentamicin MIC ≤ 2 μg/ml	15 (31.3)	72 (75)	<0.01
Tigecycline MIC ≤ 1 μg/ml^b	16 (47.1)	58 (60.4)	0.27
Suboptimal MIC values^c	10 (20.8)	14 (14.6)	0.5

Bold data are significant
DC double carbapenem, ST standard treatment, CR carbapenem resistant, MIC minimal inhibitory concentration
^aStrains resistant to at least one agent in all but two or fewer usually active antimicrobial categories
^bMIC values were available in 130 patients: 34 pts (DC group) and 96 patients (ST group)
^cGentamicin (4 μg/ml), tigecycline (2 μg/ml)

ISSN: 1364-8535