1288. Diagnostic Yield and Clinical Impact of Routine Cell Culture for Respiratory Viruses among Children with a Negative Multiplex RT-PCR Result
Session: Poster Abstract Session: Clinical Infectious Diseases: Respiratory Infections
Friday, October 28, 2016
Room: Poster Hall
Posters
  • Viral culture poster_ID Week 2016.pdf (363.8 kB)
  • Background: Polymerase chain reaction (PCR) is the reference standard for respiratory virus testing. However, cell culture may still have added value such as for the detection of viruses not in the PCR assay used. We aimed to estimate the yield of routine respiratory virus culture among children with a negative PCR and to describe the effect of a positive cell culture result on their care.

    Methods: A retrospective cohort study was performed at the Montreal Children’s Hospital from Jan. 2013 to Sept. 2015. Respiratory samples from admitted or immunocompromised patients were routinely inoculated on traditional tube cell culture monolayers if they tested negative by a PCR assay for 12 respiratory viruses. We studied patients <18 years old with a respiratory specimen negative by PCR and positive by cell culture. Duplicates (›1 additional sample during the same illness episode) and samples of sold services (medical records unavailable) were excluded from analyses. Demographics, clinical history, laboratory findings, and impact of a positive cell culture result (i.e., to guide antibiotic stoppage, antiviral treatment or hospital discharge) were collected from patients’ charts. Descriptive statistics were performed.

    Results: 4868 PCR-negative samples were inoculated in cell culture during the study period. Of those, 196 (4.0%) were cell culture positive, and 144 met study inclusion criteria. Subjects were mostly male (63.2%) and 81.9% were hospitalized; 43% were previously healthy and 14% were immunocompromised. Mean age was 2.4 ± 3.4 years. The frequency of viruses isolated and result turn-around times are listed in Table 1. Cell culture results prompted a change in management in 5 patients (3.5%), all of who had acyclovir initiated for localized HSV-1 infection. Four of these had skin or mucosal lesions that could be sampled to establish a diagnosis.
    Table 1: Viruses isolated and mean result turn-around time (TAT) for cell culture
    Viruses N (%) Mean TAT (days)
    CMV 48 (33.3%) 8.0
    Enteroviruses 28 (19.4%) 7.9
    HSV-1 24 (16.7%) 5.7
    Mumps 1 (0.7%) 6.0

    Respiratory viruses: parainfluenza (23), rhinovirus (15), RSV (3), adenovirus (1), influenza B (1)

    43 (29.9%) 12.8

    Conclusion: In children, routine viral culture on specimens that were negative by PCR has low yield and minimal clinical impact.

    Mohammad Alghounaim, MD, FAAP, Pediatrics, McGill University Health center, Montreal, QC, Canada

    Disclosures:

    M. Alghounaim, None

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.