ArticleMedical hypotheses2021
More that ACE2? NRP1 may play a central role in the underlying pathophysiological mechanism of olfactory dysfunction in COVID-19 and its association with enhanced survival.
Article in Medical hypotheses, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers, 4 of them syntheses that pooled it.
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Who cites it
33 citing papers in PubMed, 4 syntheses or guidelines pooled it, 63 citations in OpenAlex.
- Interventions for the prevention of persistent post-COVID-19 olfactory dysfunction.The Cochrane database of systematic reviews · 2022Pooled it
- Interventions for the treatment of persistent post-COVID-19 olfactory dysfunction.The Cochrane database of systematic reviews · 2022Pooled it
- Interventions for the prevention of persistent post-COVID-19 olfactory dysfunction.The Cochrane database of systematic reviews · 2021Pooled it
- Interventions for the treatment of persistent post-COVID-19 olfactory dysfunction.The Cochrane database of systematic reviews · 2021Pooled it
- Intranasal SARS-CoV-2 infection changes the transcriptome of the mouse trigeminal ganglion and brainstem: potential mechanisms underlying headache and trigeminal pain presentation in COVID-19.Journal of neuroinflammation · 2026Article
- Topical Anesthesia and Olfactory Capability: A Pilot Study.Laryngoscope investigative otolaryngology · 2025Article
- Review
- New insights into the pathogenesis of SARS-CoV-2 during and after the COVID-19 pandemic.Frontiers in immunology · 2024Review
- Unraveling the SARS-CoV-2 spike protein long-term effect on neuro-PASC.Frontiers in cellular neuroscience · 2024Article
- Mechanism and treatment of olfactory dysfunction caused by coronavirus disease 2019.Journal of translational medicine · 2023Review
- Remote psychophysical testing of smell in patients with persistent olfactory dysfunction after COVID-19.Scientific reports · 2023Article
- Olfactory impairment in COVID-19: Two methods for the assessment of olfactory function.Heliyon · 2023Article
- Epidemiological Characteristics, Pathogenesis and Clinical Implications of Sinusitis in the Era of COVID-19: A Narrative Review.Journal of asthma and allergy · 2023Review
- The immune mechanism of the nasal epithelium in COVID-19-related olfactory dysfunction.Frontiers in immunology · 2023Review
- Prevalence of Olfactory Dysfuntion in SARS-COV-2 Positive Patients.Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India · 2022Article
- Article
- Ear, nose, and throat manifestations of COVID-19 and its vaccines.World journal of clinical cases · 2022Review
- Sociodemographic Characteristics and Comorbidities of Patients With Long COVID and Persistent Olfactory Dysfunction.JAMA network open · 2022Article
- Unmasking the 'Asymptomatic' COVID-19: A Nose Question.Life (Basel, Switzerland) · 2022Article
- Chronic Rhinosinusitis and COVID-19.The journal of allergy and clinical immunology. In practice · 2022Review
Corrections and comments
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Authors and funding
3 authors at 3 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Three mechanisms have been proposed to account for COVID-19 associated olfactory dysfunction; obstruction of the olfactory cleft; epithelial injury and infection of the sustentacular supporting cells, which are known to express ACE2, or injury to the olfactory bulb due to axonal transport through olfactory sensory neurones. The absence of ACE2 expression by olfactory sensory neurones has led to the neurotropic potential of COVID-19 to be discounted. While an accumulating body of evidence supports olfactory epithelial injury as an important mechanism, this does not account for all the features of olfactory dysfunction seen in COVID-19; for example the duration of loss in some patients, evidence of changes within the olfactory bulb on MRI imaging, identification of viral particles within the olfactory bulb in post-mortem specimens and the inverse association between severity of COVID-19 and the prevalence of olfactory loss. The recent identification of a second route of viral entry mediated by NRP1 addresses many of these inconsistencies. Expression by the olfactory sensory neurones and their progenitor cells may facilitate direct injury and axonal transport to the olfactory bulb as well as a mechanism for delayed or absent recovery. Expression by regulatory T cells may play a central role in the cytokine storm. Variability in expression by age, race or gender may explain differing morbidity of infection and inverse association between anosmia and severity; in the case of higher expression there may be a higher risk of olfactory function but greater activation of regulatory T cells that may suppress the cytokine storm.
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