Summary
Background
Point-of-care (POC) SARS-CoV-2 lateral-flow antigen detection (LFD) testing in the emergency department (ED) could inform rapid infection control decisions but requirements for safe deployment have not been fully defined
Methods
Review of LFD test results, laboratory and POC-RT-PCR results and ED-performance metrics during a two-week high SARS-CoV-2 prevalence period followed by several months of falling prevalence.
Aim
Determine whether LFD testing can be safely deployed in ED to provide an effective universal SARS-CoV-2 testing capability.
Findings
93% (345/371) of COVID-19 patients left ED with a virological diagnosis during the 2-week universal LFD evaluation period compared to 77% with targeted POC-RT-PCR deployment alone, on background of approximately one-third having an NHS Track and Trace RT-PCR test-result at presentation. LFD sensitivity and specificity was 70.7% and 99.1% respectively providing a PPV of 97.7% and NPV of 86.4% with disease prevalence of 34.7%. ED discharge-delays (breaches) attributable to COVID-19 fell to 33/3532 (0.94%) compared with the preceding POC-RT-PCR period (107/4114 (2.6%); p=<0.0001). Importantly, LFD testing identified 1 or 2 clinically-unsuspected COVID-19 patients/day. Three clinically-confirmed LFD false positive patients were appropriately triaged based on LFD action-card flowchart, and only 5 of 95 false-negative LFD results were inappropriately admitted to non-COVID-19 areas where no onward-transmission was identified. LFD testing was restricted to asymptomatic patients when disease prevalence fell below 5% and detected 1–3 cases/week.
Conclusion
Universal SARS-CoV-2 LFD testing can be safely and effectively deployed in ED alongside POC-RT-PCR testing during periods of high and low disease prevalence.
【저자키워드】 SARS-CoV-2, emergency department, Nosocomial transmission, Lateral flow viral antigen detection devices, LFD, 【초록키워드】 COVID-19, review, infection control, POC, Diagnosis, RT-PCR, Laboratory, Prevalence, Disease prevalence, Sensitivity and specificity, SARS-CoV-2 testing, Patient, antigen detection, False positive, false-negative, asymptomatic patient, COVID-19 patient, Safe, Metrics, Non-COVID-19, NHS, Virological, finding, track, effective, evaluation period, trace, defined, NPV, PPV, Universal, 【제목키워드】 lateral flow, SARS-CoV-2 antigen, Safe, diagnosis of COVID-19,