Clinical and Financial Benefits of Rapid Detection of Respiratory Viruses: an Outcomes Study

Abstract

To assess the expected benefits of rapid reporting of respiratory viruses, we compared patients whose samples were processed using standard techniques such as enzyme immunoassays, shell vial assays, and culture tube assays (year 1) to patients whose samples were processed with the same standard techniques in addition to immunofluorescent testing (FA) directly on cytocentrifuged samples (year 2). The cytospin FA screened for influenza A and B viruses, respiratory syncytial virus (RSV), parainfluenza viruses 1 to 3, and adenovirus (DAKO Diagnostics Ltd.). The specificity of the cytospin FA for all viruses was 100%. The sensitivities for influenza A virus and RSV were 90 and 98%, respectively, but the sensitivities for influenza B virus and adenovirus were unacceptable (14.3 and 0%, respectively). However, since the former viruses account for >85% of our isolates from clinical specimens, the cytospin FA is an excellent screening test since the positive result was available within hours. The mean turnaround time for all positive viruses was 4.5 days in year 1 and 0.9 day in year 2 (P = 0.001). This rapid reporting resulted in physicians having access to information sooner, enabling more appropriate treatment. The mean length of stay in the hospital for inpatients with respiratory viral isolates was 10.6 days for year 1 versus 5.3 days for year 2. Mean variable costs for these patients was $7,893 in year 1 and $2,177 in year 2. After subtracting reagent costs and technological time, the savings in variable costs was $144,332/year. Summarizing, the cytospin FA markedly decreased turnaround time and was associated with decreased mortality, length of stay, and costs and with better antibiotic stewardship.

2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Health Care Settings

“…Molecular typing, onsite or outsourced, to investigate and control health care-associated outbreaks. 608 d Application of rapid diagnostic tests to support clinical decisions involving patient treatment, room selection, and implementation of control measures, including barrier precautions and use of vaccine or chemoprophylaxis agents (eg, influenza, 609-611 B pertussis,612 , RSV,613,614 and enteroviruses…”

Evaluating the impact of the multiplex respiratory virus panel polymerase chain reaction test on the clinical management of suspected respiratory viral infections in adult patients in a hospital setting

“…1,2 It is often difficult to distinguish between viral and bacterial etiologies on clinical grounds alone; however, rapid and accurate etiologic identification is important to guide patient management and hence reduce morbidity and mortality and implement appropriate infection control practices. [3][4][5] Targeted therapy is expected to decrease the risk of emergence of drug-resistant bacterial strains and of nosocomial infections, such as Clostridium difficile. 6 In the context of limited health care resources, there is interest in assessing the impact of respiratory virus diagnostic testing on antimicrobial therapy.…”

04 – Apport des explorations microbiologiques au diagnostic des infections des voies respiratoires basses

“…La méthode d'immunofluorescence directe permet en principe un diagnostic rapide en 1,5 à 2 heures. Commercialement, il existe de nombreux anticorps monoclonaux capables d'identifier individuellement ou collectivement des virus tels que le VRS, les virus para-influenza 1, 2 et 3, les adénovirus, et les virus influenza A et B [125][126][127][128][129]…”