Objective evaluation of the nasal mucosal secretion in COVID-19 patients with anosmia

COVID-19 is a new disease caused by the SARS-CoV-2 virus. The olfactory dysfunction linked to COVID-19 is not associated with rhinorrhea but there is no objective evaluation.

To evaluate nasal mucosal secretion objectively in COVID-19 patients with anosmia.

Fifty-two COVID-19 patients with anosmia and 51 healthy individuals included. Anosmia was diagnosed by subjective questionnaires. Nasal Schirmer test was done to the left and the right nasal cavity separately.

All patients had anosmia and 82.6% had gustatory dysfunction. In group 1, the mean of the nasal Schirmer test results in the right cavity was 12.4 mm, 12.01 mm in the left nasal cavity. The median wetting distance (right plus left divided by two) was calculated 12.21 mm. In group 2, the mean of the nasal Schirmer test results in the right cavity was 12.1 mm, 11.8 mm in the left nasal cavity. The median wetting distance (right plus left divided by two) was calculated11.97 mm. There was no difference between the two groups in terms of nasal schirmer.

Olfactory dysfunction and gustatory dysfunction are the two of the unknown for this disease. We evaluated the nasal mucosa secretions in COVID-19 patients with anosmia objectively to evaluate if there is inflammation in the nasal mucosa. We found no difference between healthy individuals. According to our study, SARS-CoV-2 causes anosmia without causing nasal mucosal inflammation. Invasion of the olfactory bulb and central nervous system by SARS-CoV-2 may lead to anosmia in COVID-19, which may cause olfactory dysfunction.