Impact of Rapid On-demand Molecular Diagnosis of Pediatric Seasonal Influenza on Laboratory Workflow and Testing Costs: A Retrospective Study.

Abstract

Seasonal influenza imposes a considerable burden worldwide. We aimed to evaluate impact of rapid pediatric seasonal influenza diagnosis on laboratory workflow and cost using a rapid antigen detection-based test combined with either a reverse transcriptase polymerase chain reaction (RT-PCR) or the Alere i Influenza A and B (Alere i) assay for confirmation of negative results as well as single Alere i testing on nasopharyngeal aspirates. A secondary objective was assessing performance of Alere i against RT-PCR. Effects of implementing the 3 diagnostic algorithms were assessed in the Emergency Department of Hospital Sant Joan de Déu (Barcelona, Spain) across the 2014-2015, 2015-2016 and 2016-2017 influenza seasons. Alere i performance against RT-PCR was determined during the 2015-2016 epidemic period. Median time to result decreased when using Alere i as a confirmatory test of previous antigen detection and RT-PCR results or alone (9.7vs. 3.5/2.0 and 0.7 hours, P < 0.001) along with mean testing costs (&OV0556;87.3 vs. &OV0556;38.2 and &OV0556;25.0, P < 0.001). Results available before patient discharge from the emergency department increased from 42.7% for sequential testing by antigen detection and RT-PCR to 80.0% when Alere i was utilized as a stand-alone test. Alere i sensitivity and specificity values were 96.6% (95% confidence interval: 82.8%-99.4%) and 94.4% (95% confidence interval: 86.6%-97.8%), respectively. Rapid Alere i testing facilitated efficient laboratory workflow near the patient during influenza epidemics while contributing cost savings when compared with serial testing by antigen and RT-PCR assays.