Prospective observational study reveals high multidrug resistance in ICU ventilator-associated pneumonia, highlighting eroded carbapenem efficacy and high mortality.
Key Points
To determine the bacteriological profile, antimicrobial susceptibility patterns, resistance phenotypes, and clinical outcomes of ventilator-associated pneumonia in an intensive care unit.
Conducted a single-center prospective observational study enrolling 100 consecutive mechanically ventilated adults (mean age 54.6 ± 16.2 years; 72% male) with a Clinical Pulmonary Infection Score greater than 6.
Collected endotracheal aspirate or bronchoalveolar lavage for semi-quantitative and quantitative microbiological culture, automated organism identification, and CLSI-guided antimicrobial susceptibility testing.
Gram-negative bacilli accounted for 89.5% of 105 isolates from 92 culture-positive patients, led by Acinetobacter baumannii (28.6%) and Klebsiella pneumoniae (22.9%), with 83.8% showing multidrug resistance.
Susceptibility to meropenem was 23.3% in A. baumannii and 54.2% in K. pneumoniae, whereas colistin (93.3% and 95.8%) and tigecycline (90.0% and 95.8%) demonstrated the highest in vitro activity.
Overall 28-day mortality was 30.0%, with significantly higher mortality among older patients (60.1 ± 15.2 vs 52.2 ± 16.2 years; P = 0.023) and those infected with K. pneumoniae (54.5% vs 25.7%; P = 0.018).