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

Abstract

e 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. R espiratory viruses can cause not only mild upper respiratory tract infections but severe pneumonia, especially in immunocompromised hosts. Rapid and definitive diagnosis is critical in the management of viral respiratory infections and in timely isolation of infected patients. The 2009 H1N1 pandemic revealed the need for better diagnostic tests for influenza viruses. In addition, overlapping clinical presentations impede clinicians' ability to predict causative pathogens (whether bacterial or viral) and may lead to unnecessary antimicrobial use (1, 2). Nucleic acid amplification testing (NAAT)-based methods for detection of viral pathogens are increasingly used due to their excellent sensitivity and specificity and their ability to detect a wide spectrum of viral agents. Therefore, NAAT has many potential advantages over traditional methods, such as rapid antigen testing (which is Ͻ40 to 60% sensitive for influenza in adults), direct fluorescent-antibody (DFA) testing (which requires specialized laboratory training), or viral culture (which can take up to 10 days for a result) (3). Multiplex PCR using FilmArray (BioFire Diagnostics, Inc., a bioMérieux company, Salt Lake City, UT) is an NAAT method which can detect multiple viral pathogens with a single test (4). The FilmArray respiratory viral panel (RVP) was FDA cleared in May 2011 to detect 15 respiratory viral pathogens: influenza A virus and subtypes (influenza A H1, influenza A H1 2009, and influenza A H3 viruses), influenza B virus, parainfluenza 1 virus, parainfluenza 2 virus, parainfluenza 3 virus, parainfluenza 4 virus, respiratory syncytial virus (RSV), human metapneumovirus, adenovirus, rhinovirus/enterovirus, coronavirus NL63, and coronavirus HKU1.In Febr...

Rapid detection of respiratory organisms with FilmArray respiratory panel and its impact on clinical decisions in Shanghai, China, 2016‐2018

“…In the present study, we found that 53.8% (60/112) of the patients in the FA‐RP group received antiviral treatment, which is significantly higher than that in the control group (14.3%, 10/70; P < .001). Among those patients who received a positive test result for the Influenza virus, 100% (43/43) were treated with oseltamivir that is notably higher than the 74%‐81% reported in other studies carried out in the United States . Moreover, adjustment of antibiotic therapy was reported for 69.6% (78/112) of the patients in the FA‐RP group, compared with only 5.1% (4/79) in the control group.…”

The impact of rapid molecular diagnostic testing for respiratory viruses on outcomes for emergency department patients

“…Rapid, easy‐to‐use PCR‐based respiratory virus diagnostic tests have been introduced in recent years; the GeneXpert system (Cepheid), for instance, was introduced in New South Wales in July 2017. Rapid PCR tests were expected to facilitate timely and appropriate initiation of treatment, improve outbreak prevention and infection control measures, and expedite the assessment of patients in EDs.…”

“…Other studies have also reported that hospital admission numbers were significantly lower when rapid influenza virus testing was used in EDs. An analysis of outcomes for more than 300 adults at a tertiary care centre in New York found that early diagnosis of respiratory infections was associated with significantly fewer hospitalisations of influenza‐positive patients . In a small Irish study (73 patients), the hospital admission rate for obstetric patients declined from 88% to 45% after on‐site rapid influenza PCR testing was introduced .…”

Impact of point-of-care testing for respiratory viruses on antibiotic use in adults with exacerbation of airways disease

“…Although the ResPOC study is the only published randomised controlled trial of syndromic respiratory virus testing at the pointof-care, other non-randomised, pre and post intervention studies have suggested similar benefits from rapid syndromic respiratory virus testing in terms of reducing unnecessary antibiotic use, in both paediatric and adults patients presenting to hospital. 15,16 The strengths of this study include the randomised nature of the parent study, the large overall cohort of patients studied and the pragmatic nature with broad generalisability to other UK and international centres. Its limitations include being a single-centre trial and the relatively small numbers of patients with asthma and COPD with each respiratory virus detected.…”

“…Several observational studies support the findings of ResPOC, demonstrating a reduction in unnecessary antibiotics with rapid molecular testing for respiratory viruses in a variety of clinical setting. 15,16 In addition a post hoc analysis from the trial itself suggests that the very rapid turnaround times for results seen with POCT compared to laboratory testing are critical in modifying antibiotic use in hospitalised patients. 17 Several rapid molecular test platforms for respiratory viruses are now available with the potential for deployment as POCTs in clinical areas and their use in hospitals is becoming more widespread.…”