Related Experiment Video
Updated: Mar 9, 2026

Antibiotic Efficacy Testing in an Ex vivo Model of Pseudomonas aeruginosa and Staphylococcus aureus Biofilms in the Cystic Fibrosis Lung
Published on: January 22, 2021
Colistin Dosage without Loading Dose Is Efficacious when Treating Carbapenem-Resistant Acinetobacter baumannii
Rocío Álvarez-Marín1, Rafael López-Rojas1, Juan Antonio Márquez2
1Clinical Unit of Infectious Diseases, Microbiology and Preventive Medicine Infectious Diseases Research Group Institute of Biomedicine of Seville (IBiS) University of Seville/CSIC/University Hospitals Virgen del Rocio and Virgen Macarena, Seville, Spain.
Objectives:
This study aims to analyze the mortality and the length of ICU stay (LOS) of A. baumannii VAP compared to respiratory colonization in patients with mechanical ventilation (MV).
Methods:
A prospective cohort study was performed in an ICU of adult patients (February 2010-June 2011). One hundred patients on MV with A. baumannii in lower respiratory airways were recruited, and classified as VAP or airways colonization according to CPIS criteria, with a punctuation ≥6. LOS, 30-days mortality, A. baumannii bacteremia, and clinical features including antibiotic therapy were recorded. Multivariate analysis (linear and Cox regression) and survival analysis (Kaplan-Meier curves) were performed.
Results:
Fifty-seven VAP and 43 colonized A. baumannii patients were analyzed. Among the A. baumannii strains, 99% were non-susceptible to carbapenems and the MIC90 of colistin was 0.12 mg/l. Therapy was appropriate in 94.6% of VAP patients, most of them with colistin 6 MIU/day, although in 13 (23.6%) cases colistin was started 48 hours after the onset of VAP. Mortality was similar in both groups (VAP 24.6% vs. colonized 27.9%, p = 0.7). Bacteremia and acute kidney insufficiency were associated with decreased survival (p = 0.02 and p = 0.04, respectively) in VAP patients. LOS was 21.5 (11.5-42.75) vs. 9 (6-22) days for VAP and colonized patients (p = 0.004). VAP (p = 0.003) and age (p = 0.01) were independently related to a longer LOS.
Conclusions:
Multidrug-resistant A. baumannii VAP treated with colistin does not have a different mortality compared to lower airways colonization, among patients on mechanical-ventilation, in a setting of high susceptibility to colistin of A. baumannii.
More Related Videos
06:19Author Spotlight: Characterizing Airway Environments to Advance Model Systems and Antimicrobial Discovery in Cystic Fibrosis and Chronic Respiratory Infections
Published on: October 11, 2024
09:17A Robust Pneumonia Model in Immunocompetent Rodents to Evaluate Antibacterial Efficacy against S. pneumoniae, H. influenzae, K. pneumoniae, P. aeruginosa or A. baumannii
Published on: January 2, 2017
Related Concept Videos
Estimation of k and VD of Aminoglycosides
Pneumonia IV: Management
Bacterial Pneumonia Treatment
For bacterial pneumonia, antibiotics serve as the cornerstone of therapy. Initial treatment often begins with empirical antibiotics, tailored to the anticipated causative organism and adjusted based on culture results. Key antibiotic choices include:
Acute Respiratory Failure-V
Ensure that patients are monitored continuously for their response to therapy, including changes in...
Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations
Acute Pyelonephritis II: Diagnostic Studies and Management
Cardiopulmonary Resuscitation II: ACLS Airway Management