Ventilator-Associated Pneumonia (VAP) continues to be a critical concern in intensive care units, leading to prolonged hospital stays and increased mortality rates. The European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) 2023 unveiled crucial research findings shedding light on innovative approaches to VAP diagnosis and treatment. In this article, we present a synthesis of the key discoveries from ECCMID 2023, offering insights into the evolving landscape of VAP research.
PULMIVAP Study: Precision in VAP Diagnosis
Swift and accurate diagnosis of VAP is paramount for timely treatment. The PULMIVAP study, a multicenter cohort investigation, examined the accuracy of physician-diagnosed VAP compared to established diagnostic criteria. Conducted in Italian ICUs between September 2020 and June 2022, this study enrolled adult patients with more than 48 hours of mechanical ventilation and no recent antibiotic use.
Physician diagnoses and four diagnostic criteria, including the PULMIVAP scheme, ECDC 2022 standard, leukocyte count criteria, and fever criteria, were used to identify VAP cases. Among the 186 enrolled subjects, 85% were ventilated due to neurological conditions. Notably, physician-diagnosed VAP occurred in 36.6% of patients.
The ICU’s overall mortality rate was 21%, and VAP patients endured prolonged mechanical ventilation (median 18 days vs. 9 days). Surprisingly, half of the VAP cases did not meet any of the diagnostic criteria. Of the patients meeting at least one suspected VAP definition, the criteria identified VAP cases earlier than physician diagnosis (median mechanical ventilation time: 5 days vs. 6 days).
INHALE WP3 Study: PCR’s Potential in ICU HAP/VAP
The INHALE WP3 study explored the potential of rapid multiplex PCR technology using the FilmArray™ Pneumonia Panel for diagnosing hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) in critical care settings. This multicenter randomized controlled trial assigned adult and pediatric subjects in ICUs to either standard care or the FilmArray group, guided by a prescription algorithm.
Between July 2019 and August 2021, 558 subjects from 13 hospitals participated. Importantly, 76.5% of the intervention group received antibiotic treatment within 24 hours, compared to 55.9% in the control group. On day 14, the clinical cure rate for pneumonia was 56.7% in the intervention group and 64.7% in the control group, with surprising results indicating worse treatment outcomes in the intervention group.
Phase 3 AR-301-002 (ASAP) Study: A New Approach with Tosatoxumab
Staphylococcus aureus (SA) is a prevalent Gram-positive bacterium causing VAP. The AR-301-002 (ASAP) phase 3 study evaluated the efficacy and safety of tosatoxumab (AR-301), a fully human IgG1 monoclonal antibody, in adjunctive treatment for SA VAP. Adult SA VAP patients on mechanical ventilation were randomized to receive either placebo+antibiotics or AR-301 (20 mg/kg single intravenous infusion)+antibiotics.
The study included 174 subjects, with 120 meeting microbiological pneumonia criteria. On day 21, the clinical cure rate was 57.6% in the placebo group and 68.9% in the AR-301 group. Interestingly, a greater efficacy trend was observed in patients over 65 and those with MRSA-induced VAP. AR-301 also reduced hospital stays, ICU durations, and mechanical ventilation times compared to the placebo group. Safety profiles were similar between the groups.
Summary
The findings presented at ECCMID 2023 offer valuable insights into the ongoing battle against VAP. The PULMIVAP study underscores the challenges of VAP diagnosis, highlighting the importance of refining diagnostic criteria. Meanwhile, the INHALE WP3 study brings attention to the potential of multiplex PCR technology for quicker diagnosis, although unexpected outcomes call for further investigation. In the realm of treatment, the AR-301-002 (ASAP) study introduces a novel approach with tosatoxumab, showing promise in improving clinical cure rates and reducing hospital stays for SA VAP patients. These discoveries collectively contribute to the evolving landscape of VAP research, with implications for more accurate diagnosis and innovative treatment strategies in the future.
Dr. Yimin Wang
China-Japan Friendship Hospital
