# Impact of multiplex PCR point-of-care platform implementation for respiratory pathogen detection in an emergency department with high daily patient volume

## TL;DR

A new rapid diagnostic tool for respiratory infections was tested in a busy emergency department, showing faster decisions and fewer hospital admissions.

## Contribution

First real-world validation of a broad multiplex PCR platform for respiratory pathogens in high-volume emergency departments.

## Key findings

- Spotfire detected 41% of pathogens with a median 37-minute turnaround time.
- Positive tests led to faster decisions, fewer admissions, and shorter hospital stays.
- Nearly half of pathogens identified would have been missed by conventional tests.

## Abstract

Lower respiratory tract infections (LRTIs) place a substantial burden on emergency departments (EDs) during winter outbreaks. Their microbiological diagnosis is currently based on either broad-spectrum molecular techniques performed in laboratory, with turnaround times incompatible with ED workflows, or point-of-care systems, restricted to SARS-CoV-2, influenza A/B, and RSV (quadriplex panel). The Spotfire combines rapid result and syndromic approach (10 respiratory viruses and 4 atypical bacteria), but its added value in EDs remains unassessed. During the 2023 winter, trained nurses collected nasopharyngeal swabs from adult patients with LRTI symptoms and operated the Spotfire in the ED of the Poitiers University Hospital. We described the viral epidemiology and evaluated the impact and efficacy of this rapid broad-spectrum diagnosis by comparing the management of patients with or without respiratory pathogen detected. From 15 December 2023 to 15 March 2024, 1,320 samples were analyzed with Spotfire, with a median turnaround time of 37 min and 10 uninterpretable results. A total of 540 (41%) were positive. Influenza A (30.9%), rhinovirus/enterovirus (21.1%), and SARS-CoV-2 (18.7%) were the main viruses detected, while atypical bacteria represented 8% of all pathogens. Overall, a pathogen not represented on the quadriplex panel was detected in 43% samples. Positive test results were associated with faster medical decision (380 ± 234 vs 431 ± 238 min; P < 0.001), fewer hospital admissions (65% vs 78%; P < 0.001), and shorter hospital stay (10 ± 9 vs 12 ± 14 days; P = 0.006) than negative test results. Antibiotic therapy was administered to 42 of 43 of Mycoplasma pneumoniae-positive patients (98%) compared with 110 of 1,265 (9%) negative patients. This study validated the feasibility of this new diagnostic tool in high-volume EDs improving patient flow, antimicrobial decisions, and isolation strategies.

This study provides the first real-world evidence supporting the use of a broad multiplex PCR platform for respiratory pathogens directly at the point of care in a high-volume emergency department. By enabling the simultaneous detection of 14 viruses and atypical bacteria within 20 min, this system bridges a critical gap between laboratory diagnostics and bedside clinical decision-making. Its implementation proved feasible and reliable, improving patient flow, antimicrobial stewardship, and infection control measures. Nearly half of the pathogens identified would have been missed by conventional quadriplex assays, highlighting the added diagnostic value of broader syndromic coverage. These findings are of interest to both clinicians and microbiologists, as they provide pragmatic evidence to guide the integration of advanced molecular diagnostics into acute-care workflows and to optimize patient management during respiratory infection surges.