J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website https://jocmr.elmerjournals.com

Original Article

Volume 18, Number 1, January 2026, pages 42-49

Clinical Outcomes of Aerosolized Versus Intravenous Colistin in Ventilator-Associated Pneumonia Caused by Multidrug-Resistant Gram-Negative Bacteria

**Table 1.** Patient Characteristics
	Aerosolized group (n = 30)	Intravenous group (n = 30)	P-value
Adjunctive antibiotics are presented as antibiotic classes used concomitantly with colistin. Individual antibiotic agents, dosing regimens, and duration of therapy were individualized according to antimicrobial susceptibility testing and clinical judgment and were therefore not compared between groups. IQR: interquartile range; SD: standard deviation.
Demographic characteristics
Age (years), mean ± SD	50.2 ± 20.9	53.8 ± 19.5	0.529
Male, n (%)	24 (80%)	26 (86.7%)	0.488
Height (cm), mean ± SD	166.3 ± 7.8	167.3 ± 7.4	0.589
Weight (kg), mean ± SD	61.4 ± 11.2	62.4 ± 10.6	0.681
Body mass index (kg/m²), mean ± SD	22.2 ± 3.4	22.3 ± 3.1	0.892
Comorbidities
Traumatic brain injury, No. (%)	18 (60%)	18 (60%)	0.610
Hypertension, No. (%)	12 (40%)	12 (40%)	0.890
Diabetes mellitus, No. (%)	4 (13.3%)	3 (10%)	0.689
Gout, No. (%)	3 (10%)	4 (13.3%)	0.673
Severity
SOFA score, median (IQR)	5 (3–8)	5 (2–7)	0.941
APACHE II score, mean ± SD	16.2 ± 5.2	15.8 ± 6.3	0.419
CPIS score, median (IQR)	6 (4–7)	6 (4–7)	0.427
Microbiological characteristics
A. baumannii isolated, No. (%)	20 (66.7%)	21 (70%)	0.781
K. pneumoniae isolated, No. (%)	5 (16.7%)	4 (13.3%)	0.709
P. aeruginosa isolated, No. (%)	5 (16.7%)	5 (16.7%)	1.000
Antibiotics combined
Carbapenem	19 (63.3%)	20 (66.7%)	1.000
Tigecycline	4 (13.3%)	5 (16.7%)	1.000
Vancomycin	4 (13.3%)	2 (6.7%)	0.671
Aminoglycoside	4 (13.3%)	5 (16.7%)	1.000
Quinolone	1 (3.3%)	0 (0%)	1.000

Table 1. Patient Characteristics

Aerosolized group (n = 30)

Intravenous group (n = 30)

P-value

Adjunctive antibiotics are presented as antibiotic classes used concomitantly with colistin. Individual antibiotic agents, dosing regimens, and duration of therapy were individualized according to antimicrobial susceptibility testing and clinical judgment and were therefore not compared between groups. IQR: interquartile range; SD: standard deviation.

Demographic characteristics

Age (years), mean ± SD

50.2 ± 20.9

53.8 ± 19.5

0.529

Male, n (%)

24 (80%)

26 (86.7%)

0.488

Height (cm), mean ± SD

166.3 ± 7.8

167.3 ± 7.4

0.589

Weight (kg), mean ± SD

61.4 ± 11.2

62.4 ± 10.6

0.681

Body mass index (kg/m²), mean ± SD

22.2 ± 3.4

22.3 ± 3.1

0.892

Comorbidities

Traumatic brain injury, No. (%)

18 (60%)

0.610

Hypertension, No. (%)

12 (40%)

0.890

Diabetes mellitus, No. (%)

4 (13.3%)

3 (10%)

0.689

Gout, No. (%)

3 (10%)

4 (13.3%)

0.673

Severity

SOFA score, median (IQR)

5 (3–8)

5 (2–7)

0.941

APACHE II score, mean ± SD

16.2 ± 5.2

15.8 ± 6.3

0.419

CPIS score, median (IQR)

6 (4–7)

0.427

Microbiological characteristics

A. baumannii isolated, No. (%)

20 (66.7%)

21 (70%)

0.781

K. pneumoniae isolated, No. (%)

5 (16.7%)

4 (13.3%)

0.709

P. aeruginosa isolated, No. (%)

5 (16.7%)

1.000

Antibiotics combined

Carbapenem

19 (63.3%)

20 (66.7%)

1.000

Tigecycline

4 (13.3%)

5 (16.7%)

1.000

Vancomycin

4 (13.3%)

2 (6.7%)

0.671

Aminoglycoside

4 (13.3%)

5 (16.7%)

1.000

Quinolone

1 (3.3%)

0 (0%)

1.000

**Table 2.** Clinical Outcomes
Outcome	Aerosolized group	Intravenous group	P-value	OR (95% CI)
Data were presented as No. (%) or mean ± standard deviation (SD). *P < 0.05.
Time to defervescence (days)	3.0 ± 1.2	5.0 ± 1.7	0.002*	-
Clinical success	24 (80%)	21 (70%)	0.55	1.71 (0.53–5.52)
Nephrotoxicity	4 (13.3%)	7 (23.3%)	0.50	0.51 (0.13–2.03)
Mortality	5 (16.7%)	7 (23.3%)	0.75	0.66 (0.18–2.42)
Microbiological clearance	20 (66.7%)	17 (56.7%)	0.60	1.75 (0.63–4.88)
CPIS day 0	8.5 ± 1.5	8.0 ± 1.2	0.16	-
CPIS day 7	5.0 ± 1.5	6.0 ± 1.5	0.01*	-
CPIS day 14	3.5 ± 2.0	4.0 ± 2.0	0.34	-
Duration of mechanical ventilation (days)	22.4 ± 7.6	23.5 ± 7.4	0.57	-
ICU length of stay (days)	18.7 ± 8.3	21.9 ± 8.7	0.15	-

Table 2. Clinical Outcomes

Outcome

Aerosolized group

Intravenous group

P-value

OR (95% CI)

Data were presented as No. (%) or mean ± standard deviation (SD). *P < 0.05.

Time to defervescence (days)

3.0 ± 1.2

5.0 ± 1.7

0.002*

Clinical success

24 (80%)

21 (70%)

0.55

1.71 (0.53–5.52)

Nephrotoxicity

4 (13.3%)

7 (23.3%)

0.50

0.51 (0.13–2.03)

Mortality

5 (16.7%)

7 (23.3%)

0.75

0.66 (0.18–2.42)

Microbiological clearance

20 (66.7%)

17 (56.7%)

0.60

1.75 (0.63–4.88)

CPIS day 0

8.5 ± 1.5

8.0 ± 1.2

0.16

CPIS day 7

5.0 ± 1.5

6.0 ± 1.5

0.01*

CPIS day 14

3.5 ± 2.0

4.0 ± 2.0

0.34

Duration of mechanical ventilation (days)

22.4 ± 7.6

23.5 ± 7.4

0.57

ICU length of stay (days)

18.7 ± 8.3

21.9 ± 8.7

0.15

**Table 3.** Clinical Response Efficacy by Time Point and Microbiological Characteristics
Clinical response	Aerosolized group	Intravenous group	P-value	OR (95% CI)
95% CI: 95% confidence interval; OR: odds ratio.
By time point
Day 3	20.0%	16.7%	0.877	-
Day 7	67.3%	50.0%	0.240	-
Day 10	76.7%	66.7%	0.162	-
Overall	76.7%	70.0%	0.081	-
By microbiological characteristics
A. baumannii	13/19 (68.4%)	12/21 (57.1%)	0.215	2.33 (0.72–7.58)
K. pneumoniae	3/3 (100%)	2/2 (100%)	1.000	2.25 (0.36–14.2)
P. aeruginosa	4/8 (50.0%)	3/7 (42.9%)	0.814	5.33 (0.65–43.5)

Table 3. Clinical Response Efficacy by Time Point and Microbiological Characteristics

Clinical response

Aerosolized group

Intravenous group

P-value

OR (95% CI)

95% CI: 95% confidence interval; OR: odds ratio.

By time point

Day 3

20.0%

16.7%

0.877

Day 7

67.3%

50.0%

0.240

Day 10

76.7%

66.7%

0.162

Overall

76.7%

70.0%

0.081

By microbiological characteristics

A. baumannii

13/19 (68.4%)

12/21 (57.1%)

0.215

2.33 (0.72–7.58)

K. pneumoniae

3/3 (100%)

2/2 (100%)

1.000

2.25 (0.36–14.2)

P. aeruginosa

4/8 (50.0%)

3/7 (42.9%)

0.814

5.33 (0.65–43.5)