Objective olfactory testing in patients presenting with sudden onset olfactory dysfunction as the first manifestation of confirmed COVID-19 infection

jerome lechien; pierre cabaraux; carlos chiesa-estomba; mohammad khalife; jan plzak; stephane hans; delphine martiny; christian Henriquez; Claire hopkins; sven saussez

We think this likely reflects recovery and viral clearance in some of this group. We excluded patients with pre-existing chronic rhinosinusitis or prior nasal surgery from our study and therefore it is likely that the additional otolaryngological symptoms described by almost 50% of our patients are associated with their COVID-19 infection. This is the first study providing objective smell evaluations in patients reporting loss of sense of smell during the COVID-19 pandemic. Considering all patients who performed a sniffing test, we showed that 52% were anosmic, 24% hyposmic and 24% normosmic. The same trend was observed in our both groups (anosmia ≤12 days versus anosmia >12 days) although the expected the proportion who were anosmic decreased slightly to 43% in the group with longer duration Akerlund et al. have studied the olfactory threshold (using a discrimination test with dilution of butanol) and nasal mucosa changes by acoustic rhinometry in experimentally induced common . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. It is interesting to note that 24% of patients were found to have normal olfactory function on testing. It is known that patients sometimes have difficulty rating their own sense of smell (particularly in the setting of associated nasal obstruction), [17] and the objective test results suggesting that some patients actually have normal odor identification ability may reflect this.