# Impact of Respiratory Multiplex Polymerase Chain Reaction (PCR) on Antibiotic Stewardship: A Real-World Experience

## TL;DR

This study shows that using a fast PCR test in ICU patients with respiratory sepsis helps guide better antibiotic choices, potentially improving outcomes.

## Contribution

The study demonstrates real-world effectiveness of a multiplex PCR test in guiding antibiotic stewardship in ICU patients with respiratory sepsis.

## Key findings

- BF-guided antibiotic changes were attempted in 53% of cases for de-escalation and 35% for escalation.
- Appropriate antibiotic escalation or continuation was more common than de-escalation.
- Early antibiotic modification was linked to a trend of lower hospital mortality and shorter length of stay.

## Abstract

Background: This study examined whether the use of the multiplex PCR (BioFire-FilmArray [bioMérieux, Marcy-l'Étoile, France]) (BF) technique reduced or optimized antibiotic use in patients admitted to the intensive care unit (ICU) with respiratory sepsis.

Methods: This retrospective observational study included adult patients with pulmonary sepsis admitted to the ICU, where the BF test was performed using lower respiratory samples. The primary outcome measure was any appropriate antibiotic change guided by BF within 24 hours of sending samples. Hospital mortality and length of stay (LOS) were compared between the two groups: the group in which antibiotics were appropriately changed within 24 hours of sending samples for BF and the group in which they were not.

Results: A total of 117 patients with community- and hospital-acquired respiratory sepsis were included in this study. The mean APACHE IV score was 70.5±27.2, and 34 (29.1%) patients were in shock. BF was negative in 31 samples (26.5%), whereas culture was negative in 63 samples (53.8%). BF-guided de-escalation, escalation, and no change in antibiotics were indicated in 62 episodes (53%), 41 episodes (35%), and 14 episodes (11.9%), respectively. However, these changes were achieved in 15 episodes (24.2%), 40 episodes (97.6%), and 14 episodes (100%), respectively (p<0.0001). Hospital mortality and LOS were lower in cases where antibiotic alteration was indicated and performed, compared to cases where it was not (nonsignificant).

Conclusion: The identification of the causative agent using BF was higher. Achieving the appropriateness of antibiotics through escalation or continuation of the same antibiotics was more common than de-escalation. Appropriate early modification of antibiotics was associated with a decreased trend in-hospital mortality and LOS.