Impact of Early Detection of Respiratory Viruses by Multiplex PCR Assay on Clinical Outcomes in Adult Patients

Rapid and definitive diagnosis of viral respiratory infections is imperative in patient triage and management. We compared the outcomes for adult patients with positive tests for respiratory viruses at a tertiary care center across two consecutive influenza seasons (winters of 2010-2011 and 2012). Infections were diagnosed by conventional methods in the first season and by multiplex PCR (FilmArray) in the second season. FilmArray decreased the time to diagnosis of influenza compared to conventional methods (median turnaround times of 1.7 h versus 7.7 h, respectively; P = 0.015); FilmArray also decreased the time to diagnosis of non-influenza viruses (1.5 h versus 13.5 h, respectively; P < 0.0001). Multivariate logistic regression found that a diagnosis of influenza by FilmArray was associated with significantly lower odds ratios (ORs) for admission (P = 0.046), length of stay (P = 0.040), duration of antimicrobial use (P = 0.032), and number of chest radiographs (P = 0.005), when controlling for potential confounders. We conclude that the rapid turnaround time, multiplex nature of the test (allowing simultaneous detection of an array of viruses), and superior sensitivity of FilmArray may improve the evaluation and management of patients suspected of having respiratory virus infections.