Patient characteristics
| Group | Subjects | Mean age | Females/males |
| n | yrs | n | |
| HAP | 25 | 63.1 | 6/19 |
| CAP | 26 | 57.2 | 11/15 |
| AECB | 26 | 64.5 | 8/18 |
| TB | 27 | 45.2 | 8/19 |
| Control | 25 | 48.4 | 10/15 |
HAP: hospital-acquired pneumonia
CAP: community-acquired pneumonia
AECB: acute exacerbation of chronic bronchitis
TB: tuberculosis