Clinical Efficacy, Antibiotic Resistance Genes, Virulence Factors and Outcome of Hospital-Acquired Pneumonia Induced by Carbapenemase 2-Producing with Tigecycline Treatment in the ICU.

Purpose: Tigecycline is an agent for carbapenemase-producing (KPC-KP), given its penetration into lung tissues. Our study focused on the molecular and clinical efficacy of tigecycline for hospital-acquired pneumonia (HAP) in the ICU.

Patients And Methods: A retrospective cohort study of 52 adult KPC-KP HAP patients by searching hospital medical records from January 2018 to December 2020 was established to investigate the epidemiology of KPC-KP infections for tigecycline treatment and the associated clinical efficacy of tigecycline. The KPC-KP isolates underwent multilocus sequence typing. Molecular typing, antimicrobial resistance, and virulence profiling were also analyzed by whole-genome sequencing of KPC-KP.

Results: Among 52 patients with KPC-KP, the ICU mortality rate was 14/52 (27%), and there was no significant statistical difference in mortality between the effective group and failure group ( = 0.754). However, the duration of tigecycline was statistically different between the two groups of patients (14.4 vs 10 days, =0.046). The total bacterial clearance rate was 6/52 (11.5%). There was no significant statistical difference in both groups (=0.416). Antibiotic resistance genes () and virulence gene () were negatively correlated with clinical efficacy ( = 0.011, OR = 1.237).

Conclusions: was the main carbapenemase in all strains. ST11-KL64 KPC-KP was the most common virulence factors in KPC-KP isolates. This study suggested that antibiotic resistance genes () and virulence gene () were independent mortality risk factors for patients with carbapenemase-2 producing infections, when during the tigecycline treatment. Molecular analysis of may provide an option when choosing the antimicrobial treatment.