Table 1 Characteristics of patients of polymyxin B and colistin sulfate groups

Demographic characteristics

Age Median (Min, Max)

70.00 (23.00, 89.00)

71.00 (19.00, 97.00)

Sex(Male)

52 (76.5%)

26 (72.2%)

Comorbidities

 Diabetes Mellitus

26 (38.2%)

14 (38.9%)

 Chronic Liver Diseases

14 (20.6%)

5 (13.9%)

 Chronic Kidney Diseases

23 (33.8%)

12 (33.3%)

 Cardiovascular Disease

48 (70.6%)

27 (75.0%)

 Respiratory Comorbidities

32 (47.1%)

20 (55.6%)

 Sepsis

22 (32.4%)

10 (27.8%)

 Malignant Tumor

9 (13.2%)

1 (2.8%)

 Immunosuppressants

0 (0%)

2 (5.6%)

Mechanical ventilation

 Invasive

56 (82.4%)

30 (83.3%)

 Non-invasive

6 (8.8%)

5 (13.9%)

 No mechanical ventilation

6 (8.8%)

1 (2.8%)

Infection status

 Infection site

  Pneumonia

40 (58.8%)

21 (58.3%)

  Blood

1 (1.5%)

0 (0%)

  Abdomen

3 (4.4%)

1 (2.8%)

  Urinary tract

3 (4.4%)

2 (5.6%)

  ≥ two infection sites

21 (30.9%)

12 (33.3%)

 Pathogenic bacteria

  CRAB^a

19 (27.9%)

14 (38.9%)

  CRPA^b

8 (11.8%)

4 (11.1%)

  CRKP^c

25 (36.8%)

9 (25.0%)

  Others^d

3 (4.4%)

0 (0%)

   ≥ two species of bacteria

13 (19.1%)

9 (25.0%)

Polymyxins MIC distribution^e

n = 55

n = 33

MIC = 0.5 μg/ml

50 (90.9%)

29 (87.9%)

MIC = 1 μg/ml

0 (0%)

1 (3.0%)

MIC = 2 μg/ml

4 (7.3%)

3 (9.1%)

MIC = 4 μg/ml

1 (1.8%)

0 (0%)

Therapeutic regimens

 Treatment duration (d) Median (Min, Max)

9.00 (3.00, 32.00)

11.00(3.00, 25.00)

Administration

 Intravenous drip

45 (66.2%)

20 (55.6%)

 Inhalation

5 (7.4%)

1 (2.8%)

 Intravenous and Inhalation

18 (26.5%)

15 (41.7%)

Combination

 Meropenem or Imipenem

28 (41.2%)

9 (25.0%)

 Tigecycline

15 (22.1%)

13 (36.1%)

 Cefoperazone/Sulbactam or Piperacillin/Tazobactam

25 (36.8%)

14 (38.9%)