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. 2022 Jun 10;35(5):402–411. doi: 10.3967/bes2022.056

A Case Series of Olfactory Dysfunction in Imported COVID-19 Patients: A 12-Month Follow-Up Study

Ni WANG a,&, Ming Bo YANG b,&, Pu Ye YANG c,&, Ren Bo CHEN c,&, Fei HUANG a, Nan Nan SHI c, Yan MA c, Yan ZHANG e, You XU e, Si Hong LIU f, Heng Yi LU b, Qing Qing FU d, Yi Pin FAN c, Hong Min KAN 2, Xiao Hong WANG e,#, Ya Ling GUO e,#
PMCID: PMC9187331  PMID: 35676811

Abstract

Objective

The scientific community knows little about the long-term influence of coronavirus disease 2019 (COVID-19) on olfactory dysfunction (OD). With the COVID-19 pandemic ongoing worldwide, the risk of imported cases remains high. In China, it is necessary to understand OD in imported cases.

Methods

A prospective follow-up design was adopted. A total of 11 self-reported patients with COVID-19 and OD from Xi'an No. 8 Hospital were followed between August 19, 2021, and December 12, 2021. Demographics, clinical characteristics, laboratory and radiological findings, and treatment outcomes were analyzed at admission. We surveyed the patients via telephone for recurrence and sequelae at the 1-, 6-, and 12-month follow-up.

Results

Eleven patients with OD were enrolled; of these, 54.5% (6/11) had hyposmia and 45.5% (5/11) had anosmia. 63.6% (7/11) reported OD before or on the day of admission as their initial symptom; of these, 42.9% (3/7) described OD as the only symptom. All patients in the study received combined treatment with traditional Chinese medicine and Western medicine, and 72.7% (8/11) had partially or fully recovered at discharge. In terms of OD recovery at the 12-month follow-up, 45.5% (5/11) reported at least one sequela, 81.8% (9/11) had recovered completely, 18.2% (2/11) had recovered partially, and there were no recurrent cases.

Conclusions

Our data revealed that OD frequently presented as the initial or even the only symptom among imported cases. Most OD improvements occurred in the first 2 weeks after onset, and patients with COVID-19 and OD had favorable treatment outcomes during long-term follow-up. A better understanding of the pathogenesis and appropriate treatment of OD is needed to guide clinicians in the care of these patients.

Key words: COVID-19, Olfactory, Imported cases, Hyposmia, Anosmia, Follow-up

Biographies

Biographical notes of the first authors: WANG Ni, male, born in 1981, Master, majoring in tuberculosis control and prevention

YANG Ming Bo, male, born in 1981, PhD, majoring in the prevention and treatment of viral hepatitis, cirrhosis and liver cancer

YANG Pu Ye, female, born in 1969, master of integrated Traditional Chinese and Western medicine, majoring in the prevention and treatment of infectious diseases

CHEN Ren Bo, male, born in 1980, PhD, majoring in diagnosis and treatment of chronic pathology in Chinese medicine.

Footnotes

This study was funded by the COVID-19 Project of Shaanxi Administration of Traditional Chinese Medicine [SZY-KJCYC-2020-YJ002]; the COVID-19 Project of National Administration of Traditional Chinese Medicine [2020ZYLCYJ06-4]; and the CACMS Innovation Fund [CI2021A00704].

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