Table 2.
Baseline Microbiology Characteristics
| Characteristic | Preprotocol Group (n = 137) | Postprotocol Group (n = 281) | P Value |
|---|---|---|---|
| Pneumonia classification, No. (%) | 0.26 | ||
| CAP | 54 (39) | 127 (45) | |
| HAP or VAP | 83 (61) | 154 (55) | |
| Imaging suggesting pneumonia, No. (%) | 69 (50) | 153 (54) | 0.43 |
| Respiratory culture result, No. (%) | 104 (76) | 175 (62) | 0.01 |
| Enterobacteriaceaea | 11 (8) | 26 (9) | |
| Haemophilus influenzae | 1 (1) | 5 (2) | |
| MSSA | 9 (7) | 14 (5) | |
| MRSA | 6 (4) | 7 (3) | |
| Pseudomonas | 1 (1) | 15 (5) | |
| Otherb | 9 (7) | 18 (6) | |
| Normal flora/no growth | 67 (49) | 90 (32) | |
| Respiratory culture result not available, No. (%) | 33 (24) | 106 (38) |
Abbreviations: CAP, community-acquired pneumonia; HAP, hospital-acquired pneumonia; MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-susceptible Staphylococcus aureus; VAP, ventilator-associated pneumonia.
aEnterobacteriaceae included Escherichia coli and Klebsiella, Enterobacter, and Serratia species.
bOther included Stenotrophomonas and Streptococcus species.