Numbers and percentages of “potentially” and “truly resistant” bacteria isolated in 124 episodes of hospital-acquired pneumonia classified according to the duration of mechanical ventilation and prior antimicrobial therapy
| Total | Group A | Group B | Group C | Group D | |
| Organisms n | 154 | 41 | 36 | 4 | 73 |
| “Potentially resistant” bacteria | 75 (48.8) | 6 (14.7) | 20 (55.6) | 2 (50) | 47 (64.4) |
| P. aeruginosa | 48 (31.2) | 5 (12.2) | 16 (44.5) | 1 (25) | 26 (35.6) |
| Acinetobacter spp. | 9 (5.8) | 0 | 0 | 0 | 9 (25) |
| S. maltophilia | 8 (5.2) | 1 (2.4) | 3 (8.3) | 0 | 4 (11.1) |
| MRSA | 10 (6.5) | 0 | 1 (2.8) | 1 (25) | 8 (22.2) |
| “Truly resistant” bacteria | 36 (23.4) | 2 (4.9) | 7 (19.5) | 1 (25) | 26 (35.6) |
| Ticarcillin resistant P. aeruginosa | 5 (3.2) | 1 (2.4) | 0 | 0 | 4 (5.5) |
| Acinetobacter spp. | 9 (5.8) | 0 | 0 | 0 | 9 (12.3) |
| S. maltophilia | 8 (5.2) | 1 (2.4) | 3 (8.3) | 0 | 4 (5.5) |
| MRSA | 10 (6.5) | 0 | 1 (2.8) | 1 (25) | 8 (11) |
| ESBL producing Enterobacteriaceae | 4 (2.6) | 0 | 3 (8.3) | 0 | 1 (1.4) |
Data are presented as n (%)
P. aeruginosa: Pseudomonas aeruginosa
S. maltophilia: Stenotrophomonas maltophilia
MRSA: methicillin resistant Staphylococcus aureus
ESBL: extended-spectrum β‐lactamase