Olfactory dysfunction quantified by olfactometry in patients with SARS-Cov-2 infection

Abstract

Objective: To quantify olfactory dysfunction by olfactometry in patients with laboratory confirmed SARS-Cov-2 infection.Methods: Patients from a particular Spanish health area with SARS-Cov-2 infection were recruited to study the loss of smell. Olfactometry was performed using the Sniffin Sticks test. The following clinical symtoms were studied: ENT symptoms related to infection, duration of sensorineural loss, subjective and objective score of loss of smell, and its temporal relationship with other systemic symptoms.Results: A total of 51 patients with SARS-Cov-2 infection completed the study. A total of 86.3% reported subjective loss of smell capacity. Objective loss of olfactory ability was quantified by olfactometry in 22% of patients. Statistical significance was demonstrated between the group of patients with anosmia/hyposmia and the Sniffin Sticks test (p-value: 0.013). The most frequent ENT symptoms in patients with quantified olfactory loss consisted of nasal obstruction, absence of rhinorrhea, sore throat, and ear pain. The subjective olfactory recovery rate prior to performing olfactometry was 64.3% of the sample. A total of 77% of patients in whom olfactory loss was quantified by olfactometry reported a subjective duration of more than 15 days.Conclusion: Olfactory dysfunction is an objective clinical finding in patients with SARS- Cov-2 infection. Its persistence has been demonstrated beyond the first month after infection. Their quantitative study should be continued to determine the recovery rate and its possible long-term sequelae, as well as treatments to improve the quality of life of these patients.