Table 2 The pathogen results of pneumonia between immunocompetent and immunocompromised group

One virus

305 (82.4)

396 (90.8)

< 0.001

Two or more viruses

65 (17.6)

40 (9.2)

< 0.001

 Cytomegalovirus

57 (15.4)

12 (2.8)

< 0.001

 Influenza A virus

63 (17.0)

165 (37.8)

< 0.001

 Influenza B virus

20 (5.4)

25 (5.7)

0.840

 Rhinovirus

1 (0.3)

6 (1.4)

0.092

 Respiratory syncytial virus

48 (13.0)

65 (14.9)

0.430

 Adenovirus

9 (2.4)

14 (3.2)

0.508

 Parainfluenza virus

10 (2.7)

11 (2.5)

0.873

 Human metapneumovirus

1 (0.3)

0 (0)

0.277

 HSV-1

3 (0.8)

0 (0)

0.060

 Cytomegalovirus

158 (42.7)

10 (2.3)

< 0.001

 Influenza A virus

23 (6.2)

36 (8.3)

0.268

 Influenza B virus

3 (0.8)

5 (1.1)

0.632

 Rhinovirus

7 (1.9)

31 (7.1)

< 0.001

 Respiratory syncytial virus

21 (5.7)

25 (5.7)

0.972

 Adenovirus

5 (1.4)

32 (7.3)

< 0.001

 Parainfluenza virus

17 (4.6)

33 (7.6)

0.081

 Human metapneumovirus

0 (0)

3 (0.7)

0.110

Pathogenic types of coinfections

204 (55.1)

101 (23.2)

< 0.001

Bacteria

51 (13.8)

31 (7.1)

0.002

 Streptococcus pneumoniae

1 (0.3)

5 (1.1)

0.149

 Streptococcus constellatus

1 (0.3)

0 (0)

0.277

 Haemophilus influenzae

1 (0.3)

0 (0)

0.277

 Staphylococcus aureus

11 (3.0)

11 (2.5)

0.696

 Escherichia coli

3 (0.8)

1 (0.2)

0.242

 Enterobacter aerogenes

0 (0)

1 (0.2)

0.357

 Enterobacter cloacae

2 (0.5)

0 (0)

0.470

 Klebsiella pneumoniae

15 (4.1)

9 (2.1)

0.098

 Pseudomonas

11 (3.0)

4 (0.9)

0.031

 Proteus mirabilis

2 (0.5)

0 (0)

0.470

 Acinetobacter

2 (0.5)

0 (0)

0.470

 Nocardia

2 (0.5)

0 (0)

0.470

 Atypical

11 (3.0)

23 (5.3)

0.105

 Mycoplasma pneumoniae

6 (1.6)

23 (5.3)

0.006

 Legionella

5 (1.4)

0 (0)

0.015

Pneumocystis

83 (22.4)

0 (0)

< 0.001

Aspergillus

52 (14.1)

47 (10.8)

0.158

Mycobacterium tuberculosis

6 (1.6)

0 (0)

0.008

Non-tuberculosis mycobacteria

1 (0.3)

0 (0)

0.277

Pathogens in nosocomial infection

134 (36.2)

168 (38.5)

0.498

 Acinetobacter

31 (8.4)

52 (11.9)

0.099

 Pseudomonas

32 (8.6)

41 (9.4)

0.710

 Klebsiella pneumoniae

14 (3.8)

17 (3.9)

0.932

 Burkholderia

11 (3.0)

17 (3.9)

0.474

 Enterococcus

6 (1.6)

2 (0.5)

0.097

 Enterobacter cloacae

3 (0.8)

0 (0)

0.060

 Escherichia coli

4 (1.1)

1 (0.2)

0.125

 Proteus mirabilis

0 (0)

2 (0.5)

0.192

 Stenotrophomonas maltophilia

4 (1.1)

11 (2.5)

0.131

 Corynebacterium striatum

6 (1.6)

11 (2.5)

0.375

 Staphylococcus aureus

4 (1.1)

0 (0)

0.030

 Rolstonia mannitolytica

1 (0.3)

5 (1.1)

0.149

 Other bacteria

5 (1.4)

3 (0.7)

0.344

 Aspergillus

12 (3.2)

6 (1.4)

0.074

 Trichosporon asahii

1 (0.3)

0 (0)

0.277

Only one virus

123 (33.2)

259 (59.4)

< 0.001

>one organism

247 (66.8)

177 (40.6)

< 0.001