Risk factors and clinical responses of pneumonia patients with colistin-resistant Acinetobacter baumannii-calcoaceticus

Table 1 Demographic data and clinical characteristics of patients with ventilator-associated pneumonia due to colistin-resistant and colistin-susceptible Acinetobacter baumannii- calcoaceticus complex

Variable	Total, n = 124	CRABC group, n = 16	CSABC group, n = 108	P-value
Male sex (%)	63 (50.8)	13 (81.3)	50 (46.3)	0.019
Age, med ± (min-max)	73.0 ± (18-91)	59.5 ± (18-86)	74.0 ± (18-91)	0.022
Comorbidity
Diabetes mellitus (%)	35 (28.2)	5 (31.5)	30 (27.8)	0.771
Chronic renal failure (%)	11 (8.9)	0 (0.0)	11 (10.2)	0.356
Chronic obstructive lung disease (%)	33 (26.6)	4 (25.0)	29 (26.9)	1.000
Hypertension (%)	57 (46.0)	8 (50.0)	49 (45.4)	0.938
Congestive heart failure (%)	25 (20.2)	4 (25.0)	21 (19.4)	0.738
Malignity (%)	30 (24.2)	2 (12.5)	28 (25.9)	0.353
Cerebrovascular disease (%)	24 (19.4)	1 (6.3)	23 (21.3)	0.305
Trauma (%)	8 (6.5)	3 (18.8)	5 (4.6)	0.066
Operation (%)	24 (19.4)	2 (12.5)	22 (20.4)	0.735
Immunosuppression (%)	9 (7.3)	1 (6.3)	8 (7.4)	1.000
Obesity (%)	12 (9.7)	3 (18.8)	9 (8.3)	0.186
Duration of mechanical ventilation before diagnosis, med ± min-max	11 ± (2-450)	12 ± (4-50)	11 ± (2-450)	0.872
Total length of ICU stays, med ± min-max	45.5 ± (5-540)	49.0 ± (11-305)	43.0 ± (5-540)	0.685
Central venous catheterization (%)	67 (54.0)	9 (56.3)	58 (53.7)	1.000
Urethral catheterization (%)	114 (91.9)	14 (87.5)	100 (92.6)	0.616
Total parenteral nutrition (%)	21 (16.9)	6 (37.5)	15 (13.9)	0.030
Prior receipt of colistin (%)	11 (8.9)	6 (37.5)	5 (4.6)	0.001
Prior receipt of carbapenems (%)	68 (54.8)	10 (62.5)	58 (53.7)	0.696
Prior receipt of linezolid (%)	6 (4.8)	1 (6.3)	5 (4.6)	0.571
Prior receipt of ampicillin/sulbactam (%)	19 (15.3)	1 (6.3)	18 (16.7)	0.462
Prior receipt of flouroquinolones (%)	51 (41.1)	5 (31.3)	46 (42.6)	0.556
Prior receipt of teicoplanin (%)	25 (20.2)	6 (37.5)	19 (17.6)	0.091
Prior receipt of piperacillin/tazobactam (%)	19 (15.3)	1 (6.3)	18 (16.7)	0.462
Prior receipt of ceftriaxone (%)	9 (7.3)	0 (0.0)	9 (8.3)	0.603
Presence of bacteremia (%)	3 (2.4)	2 (12.5)	1 (0.9)	0.044
APACHE II scores, med ± min-max	14. 0 ± (5-28)	22.5 ± (17-28)	12.0 ± (5-22)	< 0.001
SOFA scores, med ± min-max	9.0 ± (3-20)	9 ± (7-18)	9 ± (3-20)	0.546
Clinical response (%)	71 (61.3)	11 (68.8)	65 (60.2)	0.703
Laboratory response (%)	82 (66.1)	13 (81.3)	69 (63.9)	0.277
Radiological response (%)	65 (52.4)	10 (62.5)	55 (52.9)	0.551
Microbiological response (%)	67 (54.0)	9 (56.3)	58 (53.7)	1.000
Duration of microbiological cure, med ± (min-max)	4 ± (2-10)	6 ± (3-10)	3 ± (2-7)	<0.001
In-hospital mortality (%)	77 (62.1)	6 (37.5)	71 (65.7)	0.058
VAP-related mortality (%)	50 (40.3)	5 (31.3)	45 (41.7)	0.603

VAP: Ventilator associated pneumonia; CRABC: Colistin resistant Acinetobacter baumannii-calcoaceticus complex; CSABC: Colistin susceptible Acinetobacter baumannii-calcoaceticus complex; APACHE: High Acute Physiology and Chronic Health Evaluation; SOFA: Sequential Organ Failure Assessment.