Table 2.
Identity of pathogens in patients with COPD exacerbation
| Pathogen | Comprehensive real-time PCR
|
Conventional method | Total | ||
|---|---|---|---|---|---|
| NPS | Sputum | Total | |||
| Pathogens detected from samples | 25 (50) | 24 (48) | 32 (64) | 26 (52) | 44 (88) |
| Single pathogen | 21 (42) | 19 (38) | 24 (48) | 21 (42) | 28 (56) |
| Mixed pathogen | 4 (8) | 5 (10) | 8 (16) | 5 (10) | 16 (32) |
| Viral pathogen* | 15 (30) | 9 (18) | 16 (32) | 4 (8) | 17 (34) |
| Influenza virus | 7 (14) | 4 (8) | 7 (14) | 5 (10) | 8 (16) |
| Influenza virus A | 6 (12) | 3 (6) | 6 (14) | 4 (8) | 7 (14) |
| Influenza virus B | 1 (2) | 1 (2) | 1 (2) | 1 (2) | 1 (2) |
| Rhinovirus | 2 (4) | 0 (2) | 2 (4) | ND | 2 (4) |
| Respiratory syncytial virus | 4 (8) | 2 (4) | 4 (8) | ND | 4 (8) |
| Respiratory syncytial virus subgroup A | 2 (4) | 1 (2) | 2 (4) | ND | 2 (4) |
| Respiratory syncytial virus subgroup B | 2 (4) | 1 (2) | 2 (4) | ND | 2 (4) |
| Parainfluenza virus | 3 (6) | 3 (6) | 4 (8) | ND | 4 (8) |
| Parainfluenza virus type 1 | 1 (2) | 1 (2) | 1 (2) | ND | 1 (2) |
| Parainfluenza virus type 3 | 2 (4) | 2 (4) | 3 (6) | ND | 3 (6) |
| Bacterial pathogen* | 13 (26) | 17 (34) | 21 (42) | 23 (46) | 22 (44) |
| Streptococcus pneumoniae | 7 (14) | 11 (22) | 11 (22) | 10 (20) | 13 (26) |
| Haemophilus influenzae | 3 (6) | 8 (16) | 9 (18) | 2 (4) | 9 (18) |
| Mycoplasma pneumoniae | 3 (6) | 1 (2) | 4 (8) | 0 (0) | 4 (8) |
| Chlamydophila pneumoniae | 1 (2) | 0 (0) | 1 (2) | 0 (0) | 1 (2) |
| Staphylococcus aureus | ND | ND | ND | 5 (10) | 5 (10) |
| Enteric/nonfermenting Gram-negative bacilli** | ND | ND | ND | 11 (22) | 11 (22) |
| No pathogen detected | 25 (50) | 26 (52) | 18 (36) | 24 (48) | 6 (12) |
Notes: Data are presented as the number (percentage) of patients.
*
Some overlap exists.
**
Enteric or nonfermenting Gram-negative bacilli, Pseudomonas aeruginosa (4), Enterobacter cloacae (3), Klebsiella pneumoniae (1), Serratia marcescens (1), Proteus mirabilis (1), Acinetobactor baumanii (1), Stenotrophomonas maltophilia (1).
Abbreviations: COPD, chronic obstructive pulmonary disease; ND, not determined; NPS, nasopharyngeal swab; PCR, polymerase chain reaction.