ArticleOpen forum infectious diseases2020
Olfactory Dysfunction in Coronavirus Disease 2019 Patients: Observational Cohort Study and Systematic Review.
Article in Open forum infectious diseases, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 60 papers, 8 of them syntheses that pooled it.
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Who cites it
60 citing papers in PubMed, 8 syntheses or guidelines pooled it, 114 citations in OpenAlex.
- Taste loss as a distinct symptom of COVID-19: a systematic review and meta-analysis.Chemical senses · 2023Pooled it
- The assessment of qualitative olfactory dysfunction in COVID-19 patients: a systematic review of tools and their content validity.Frontiers in psychology · 2023Pooled it
- Neurological and Head/Eyes/Ears/Nose/Throat Manifestations of COVID-19: A Systematic Review and Meta-Analysis.The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques · 2022Pooled it
- The D614G Virus Mutation Enhances Anosmia in COVID-19 Patients: Evidence from a Systematic Review and Meta-analysis of Studies from South Asia.ACS chemical neuroscience · 2021Pooled it
- Olfactory dysfunction in aging and neurodegenerative diseases.Ageing research reviews · 2021Pooled it
- Regional and Chronological Variation of Chemosensory Dysfunction in COVID-19: a Meta-Analysis.Journal of Korean medical science · 2021Pooled it
- Frequency and Clinical Utility of Olfactory Dysfunction in COVID-19: a Systematic Review and Meta-analysis.Current allergy and asthma reports · 2020Pooled it
- Prevalence of Chemosensory Dysfunction in COVID-19 Patients: A Systematic Review and Meta-analysis Reveals Significant Ethnic Differences.ACS chemical neuroscience · 2020Pooled it
- Viral Etiologies and Histopathological Features of Olfactory Dysfunction: A Systematic Review.Health science reports · 2025Review
- To study the impact of COVID-19 on the epidemiological characteristics of allergic rhinitis based on local big data in China.Scientific reports · 2024Article
- Assessment of smell disturbances 6 months after COVID-19 in Polish population.Scientific reports · 2024Article
- Article
- Chronic COVID-19 infection in an immunosuppressed patient shows changes in lineage over time: a case report.Virology journal · 2024Article
- Prevalence and Factors Associated with Olfactory Dysfunction in Individuals with COVID-19 in Brazil: A Study of 20,669 Cases from 2020 to 2021.Medical principles and practice : international journal of the Kuwait University, Health Science Centre · 2024Article
- Intranasal infection by SARS-CoV-2 Omicron variants can induce inflammatory brain damage in newly weaned hamsters.Emerging microbes & infections · 2023Article
- Recovery Patterns of COVID-19 Related Smell Disorders: An Analysis of the Available Evidence.Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India · 2023Article
- A Pilot Study of Short-Course Oral Vitamin A and Aerosolised Diffuser Olfactory Training for the Treatment of Smell Loss in Long COVID.Brain sciences · 2023Article
- Prevalence of Self-Reported Anosmia and Ageusia in Elderly Patients Who Had Been Previously Hospitalized by SARS-CoV-2: The LONG-COVID-EXP Multicenter Study.Journal of clinical medicine · 2023Article
- The immune mechanism of the nasal epithelium in COVID-19-related olfactory dysfunction.Frontiers in immunology · 2023Review
- Understanding olfactory dysfunction in the COVID-19 era: insights from a cross-sectional survey of the Saudi community.Frontiers in public health · 2023Article
Corrections and comments
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Authors and funding
23 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundOlfactory dysfunction (OD) has been reported in coronavirus disease 2019 (COVID-19). However, there are knowledge gaps about the severity, prevalence, etiology, and duration of OD in COVID-19 patients.
methodsOlfactory function was assessed in all participants using questionnaires and the butanol threshold test (BTT). Patients with COVID-19 and abnormal olfaction were further evaluated using the smell identification test (SIT), sinus imaging, and nasoendoscopy. Selected patients received nasal biopsies. Systematic review was performed according to PRISMA guidelines. PubMed items from January 1, 2020 to April 23, 2020 were searched. Studies that reported clinical data on olfactory disturbances in COVID-19 patients were analyzed.
resultsWe included 18 COVID-19 patients and 18 controls. Among COVID-19 patients, 12 of 18 (67%) reported olfactory symptoms and OD was confirmed in 6 patients by BTT and SIT. Olfactory dysfunction was the only symptom in 2 patients. Mean BTT score of patients was worse than controls (
conclusionsOlfactory dysfunction is common in COVID-19 and may be the only symptom. Coronavirus disease 2019-related OD can be severe and prolonged. Mucosal infiltration by CD68
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