Table 2 The difference of patient characteristics, pulmonary function, and serum markers between AE-IIPs and pneumonia

 Age

74 (62 to 85)

75 (66 to 83)

 Sex

66

18

 Men (%)

83.54%

85.71%

 Smoking history

61

16

  Yes (%)

77.22%

76.19%

 Current smoker

13

3

  (%)

16.46%

14.29%

 High fever

43

17

  Yes (%)

54.43%

80.91%

 Sore throat

35

19

  Yes (%)

44.31%

90.48%

 Worsening cough

50

15

  Yes (%)

63.29%

71.42%

 Worsening dyspnea

75

18

  Yes (%)

94.94%

85.72%

Pre-existing CF-IIPs

 IPF

59

17

 UCIP

20

4

Prior treatment

 No treatment

47

8

 Corticosteroid

9

2

 Corticosteroid + IS

6

2

 Pirfenidone

9

2

 Nintedanib

4

4

 Corticosteroid + Nintedanib

4

3

 P/F ratio

168 (83.2 to 344.1)

n = 79

246 (173.7 to 340.5)

n = 18

 FVC (L)

2.35 (0.94 to 3.01)

n = 39

2.19 (1.43 to 3.22)

n = 17

 %FVC (%)

65.55 (39.85 to 84.02)

n = 39

70.11 (41.98 to 102.22)

n = 17

 VC (L)

2.49 (1.33 to 3.05)

n = 39

2.09 (1.24 to 3.04)

n = 17

 %VC (%)

70.70 (44.60 to 90.22)

n = 39

65.21 (40.02 to 101.61)

n = 17

 DLco (mL/min/mmHg)

7.29 (3.85 to 11.35)

n = 30

5.04 (2.37 to 8.73)

n = 17

 %DLco (%)

29.90 (16.55 to 40.02)

n = 30

21.00 (10.71 to 40.02)

n = 17

 KL-6 (IU/L)

1117 (572 to 2701)

n = 79

517 (296 to 2348)

n = 21

 SP-D (mg/dL)

364 (45 to 2711)

n = 63

107 (44 to 303)

n = 17

 LDH (IU/L)

365 (193 to 539)

n = 79

231 (157 to 359)

n = 21

 WBC (/μL)

10,700 (6300 to 15,400)

n = 79

9900 (5480 to 17,880)

n = 21

 CRP (mg/dL)

8.5 (0.7 to 25)

n = 79

16.4 (2.2 to 35.8)

n = 21

 Procalcitonin (ng/mL)

0.12 (0.01 to 0.74)

n = 70

1.86 (0.46 to 11.21)

n = 19

 D-dimer (mg/dL)

3.6 (1.38 to 74.2)

n = 74

2.3 (1.2 to 4.1)

n = 19