key: cord-0835446-c7uleka0
authors: Mariño‐Sánchez, Franklin; Santamaría, Alfonso; de los Santos, Gonzalo; Alobid, Isam; Mullol, Joaquim
title: Psychophysical olfactory testing in COVID‐19: is smell function really impaired in nearly all patients?
date: 2020-06-04
journal: Int Forum Allergy Rhinol
DOI: 10.1002/alr.22639
sha: 136fee648bb6cba8d9e7e0598a13a8a8c3355cff
doc_id: 835446
cord_uid: c7uleka0

nan

On the basis of the evidence mentioned above, we believe that the 98% smell dysfunction prevalence in COVID-19 Iranian patients reported by Moein et al. probably doesn't reflect reality, since they used a smell test designed for the American population that has proved to be culturally inadequate for the Persian population. Additionally, the authors don't specify inclusion and exclusion criteria for the patients from the control group, who were taken from an earlier study database. Also, as the control group consisted of healthy subjects rather than negative SARS-CoV-2 PCR patients but with similar symptoms, the frequency of loss of smell could also be due to viral (common cold) or post-viral infection.

We believe that Moen et al. should re-analyze their data, using only the odorants of UPSIT valid for the Iranian population in order to portray a more realistic clinical picture about the prevalence of smell dysfunction in COVID-19 patients.

The public should definitely be informed that smell impairment is frequent in viral infections, and can often be presented as an early symptom in COVID-19. However, patients and physicians at healthcare systems should not assume that a normal UPSIT score when exploring olfaction means a low probability of having a SARS-CoV-2 infection. 

Smell Dysfunction: A Biomarker for COVID-19

University of Pennsylvania Smell Identification on Iranian Population

Iran Smell Identification Test (Iran-SIT): a Modified Version of the University of Pennsylvania Smell Identification Test (UPSIT) for Iranian Population

Evaluation of Culturally-Familiar Odorants for a Persian Smell Identification Test

Validity and Reliability of Persian Smell Identification Test

Competing interests: none