What do we know about smell and taste dysfunction by SARS-CoV-2. Predictive Value of the Venezuelan Olfactory test and RT-PCR analysis in viral infection diagnosis

  1. Rosalinda Pieruzzini
  2. Carlos Ayala-Grosso
  3. Jose de Jesus Navas
  4. Wilneg Rodríguez
  5. Nathalia Parra
  6. Emily Luque
  7. Aida Sánchez-Gago
  8. Scarleth González
  9. Alexandra Hagobian
  10. Angeline Grullón
  11. Karen Díaz
  12. Mariano Morales
  13. Melanie De Jesús
  14. Sonia Peña
  15. Luis Rodríguez
  16. Luis L Peña
  17. Ana Asaro
  18. Magda Magris

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Abstract

Background

Smell and taste disorders are reported very frequently and at an early stage in the evolution of the infectious disease caused by the SARS-CoV-2. These symptoms could be sensitive and specific to establish the condition of the infection, and may suggest the flow of decisions as to further therapy. We asked whether smell and taste impairment are earlier and more sensitive symptoms than the RT-PCR molecular assays for SARS-CoV-2 detection.

Methodology

Subjects (N=275) with a probable COVID19 diagnosis were classified as follows: Symptomatic with chemosensory dysfunction, symptomatic without chemosensory dysfunction, and asymptomatic. Subjects received a general clinical and otorhinolaryngology examination. Evaluation of the chemosensory dysfunction was performed by means of the Venezuelan Olfactory Test and taste test. Nasal swabs and blood samples were analyzed by real-time polymerase chain reaction analysis (RT-PCR) and a rapid diagnostic test to detect the SARS-CoV-2 virus and antiviral antibodies, respectively. Patients had access to molecular tests and smell and taste evaluations every 3 to 5 days until they recovered.

Results

Out of 44 patients that were positive for RT-PCR SARS-CoV-2: 45.83% had smell and taste disorders and COVID19 symptoms, 23.61% did not have smell or taste disorders, but had COVID19 symptoms, and 30.55% were asymptomatic. Mild hyposmia and hypogeusia account for the most frequent chemosensory disorders accompanying common SARS-CoV-2 symptoms. Time to recover from the chemosensory dysfunction ranges from 3 to 14 days, up to a maximum of 5 weeks, while RT-PCR becomes negative after 21 days and up to 35 days in some cases. The Venezuelan Olfactory Test and taste test has a 61.68% positive predictive value, 45.83% sensitivity, and 68.7% specificity for SARS-CoV-2 infection.

Conclusions

Smell and taste disorders are frequent symptoms of SARS-CoV-2 infection, but not a significant predictor of the disease, as compared to the molecular RT-PCR test.

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    SciScore for 10.1101/2020.11.25.20238998: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board StatementIRB: Samples collected for RT-PCR testing for SARS-CoV-2 detection were processed by the Virology Service of the “Rafael Rangel” National Hygiene Institute of the Ministry of the People’s Power for Health in Caracas, Venezuela. Ethical Approval: Collection and analysis of data were approved by the Bioethical committee of the “Carlos Arvelo” University Military Hospital of Caracas.
    Consent: All studies were conducted in compliance with the Declaration of Helsinki, and all participants signed an informed consent.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    Antibodies
    SentencesResources
    Batch: 20200307) were used to determine IgG/IgM antibodies.
    determine IgG/IgM
    suggested: None
    The sample is placed on a nitrocellulose (NC) membrane that has been prepared with rat anti-IgM antibodies and human IgG antibodies, and sheep anti-rat polyclonal antibodies.
    anti-IgM
    suggested: None
    human IgG
    suggested: None
    anti-rat polyclonal antibodies.
    suggested: None
    When there are no IgM or IgG antibodies in the sample, there is only the quality control line and the result is negative.
    IgG
    suggested: None

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: An explicit section about the limitations of the techniques employed in this study was not found. We encourage authors to address study limitations.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  2. Version published to 10.1101/2020.11.25.20238998v1 on medRxiv