Potential Impact of Rapid Molecular Microbiologic Diagnosis for Mechanically Ventilated Children in Intensive Care with Suspected Pneumonia

Abstract

Background: Lower respiratory tract infections (LRTIs) remain a leading cause of community-acquired and nosocomial infection in children and a common indication for antimicrobial use and intensive care admission. Determining the causative pathogen for LRTIs is difficult and traditional culture-based methods are labor- and time-intensive. Emerging molecular diagnostic tools may identify pathogens and detect antimicrobial resistance more quickly, to enable earlier targeted antimicrobial therapy. Methods: This is a single-center, prospective observational laboratory study evaluating the use of the Biofire FilmArray pneumonia panel (FA-PP) (BioFire Diagnostics, Salt Lake City, UT) for bronchoalveolar lavage specimens from mechanically ventilated children admitted with suspected or presumed pneumonia. We aimed to determine its feasibility and utility for identifying pathogens, antimicrobial resistance and its potential influence on antibiotic prescribing. Results: We analyzed 50 samples taken from 41 children with a median age of 6 months. Positive agreement between culture and FA-PP was 83% and negative agreement was 76%. Agreement between FA-PP (mecA/C or MREJ) and culture was high for methicillin-resistant Staphylococcus aureus. In 3 cases, extended-spectrum beta-lactamase-producing Gram-negative organisms were detected by culture and not FA-PP. Hypothetically, FA-PP results would have affected antimicrobial prescribing in approximately half the cases (24, 48%). Conclusions: FA-PP is a useful adjunct to traditional culture methods in mechanically ventilated children with LRTIs and may influence clinical decision-making regarding antibiotic escalation or stewardship.