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Dell’Aquila M, Cafiero C, Micera A, Stigliano E, Ottaiano MP, Benincasa G, Schiavone B, Guidobaldi L, Santacroce L, Pisconti S, Arena V, Palmirotta R. SARS-CoV-2-Related Olfactory Dysfunction: Autopsy Findings, Histopathology, and Evaluation of Viral RNA and ACE2 Expression in Olfactory Bulbs. Biomedicines 2024; 12:830. [PMID: 38672185 PMCID: PMC11048640 DOI: 10.3390/biomedicines12040830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 03/29/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
BACKGROUND The COVID-19 pandemic has been a health emergency with a significant impact on the world due to its high infectiousness. The disease, primarily identified in the lower respiratory tract, develops with numerous clinical symptoms affecting multiple organs and displays a clinical finding of anosmia. Several authors have investigated the pathogenetic mechanisms of the olfactory disturbances caused by SARS-CoV-2 infection, proposing different hypotheses and showing contradictory results. Since uncertainties remain about possible virus neurotropism and direct damage to the olfactory bulb, we investigated the expression of SARS-CoV-2 as well as ACE2 receptor transcripts in autoptic lung and olfactory bulb tissues, with respect to the histopathological features. METHODS Twenty-five COVID-19 olfactory bulbs and lung tissues were randomly collected from 200 initial autopsies performed during the COVID-19 pandemic. Routine diagnosis was based on clinical and radiological findings and were confirmed with post-mortem swabs. Real-time RT-PCR for SARS-CoV-2 and ACE2 receptor RNA was carried out on autoptic FFPE lung and olfactory bulb tissues. Histological staining was performed on tissue specimens and compared with the molecular data. RESULTS While real-time RT-PCR for SARS-CoV-2 was positive in 23 out of 25 lung samples, the viral RNA expression was absent in olfactory bulbs. ACE2-receptor RNA was present in all tissues examined, being highly expressed in lung samples than olfactory bulbs. CONCLUSIONS Our finding suggests that COVID-19 anosmia is not only due to neurotropism and the direct action of SARS-CoV-2 entering the olfactory bulb. The mechanism of SARS-CoV-2 neuropathogenesis in the olfactory bulb requires a better elucidation and further research studies to mitigate the olfactory bulb damage associated with virus action.
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Affiliation(s)
- Marco Dell’Aquila
- Anatomic Pathology Unit, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy; (M.D.); (E.S.); (V.A.)
- Pathology Unit, Belcolle Hospital, ASL Viterbo, 01100 Viterbo, Italy
| | - Concetta Cafiero
- Medical Oncology, SG Moscati Hospital, 74010 Statte, Italy;
- Anatomic Pathology Unit, Fabrizio Spaziani Hospital, 03100 Frosinone, Italy
| | - Alessandra Micera
- Research and Development Laboratory for Biochemical, Molecular and Cellular Applications in Ophthalmological Science, IRCCS–Fondazione Bietti, 00184 Rome, Italy
| | - Egidio Stigliano
- Anatomic Pathology Unit, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy; (M.D.); (E.S.); (V.A.)
| | - Maria Pia Ottaiano
- Department of Clinical Pathology and Molecular Biology, Pineta Grande Hospital, 81030 Castel Volturno, Italy; (M.P.O.); (G.B.); (B.S.)
| | - Giulio Benincasa
- Department of Clinical Pathology and Molecular Biology, Pineta Grande Hospital, 81030 Castel Volturno, Italy; (M.P.O.); (G.B.); (B.S.)
| | - Beniamino Schiavone
- Department of Clinical Pathology and Molecular Biology, Pineta Grande Hospital, 81030 Castel Volturno, Italy; (M.P.O.); (G.B.); (B.S.)
| | - Leo Guidobaldi
- Cytodiagnostic Unit, Section of Pathology Sandro Pertini Hospital, ASL Rm2, 00157 Rome, Italy;
| | - Luigi Santacroce
- Section of Microbiology and Virology, Interdisciplinary Department of Medicine, School of Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy;
| | | | - Vincenzo Arena
- Anatomic Pathology Unit, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy; (M.D.); (E.S.); (V.A.)
| | - Raffaele Palmirotta
- Section of Sciences and Technologies of Laboratory Medicine, Interdisciplinary Department of Medicine, School of Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy;
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Parlak AE, Selçuk ÖT, Yilmaz GÖ, Aydenizoz D, Selçuk NT, Öcal R, Seyman D, Yilmaz M, Eyigör H. Olfactory Bulb Volume and Morphology Changes in COVID-19 Patients With Olfactory Disorders Using Magnetic Resonance Imaging. J Comput Assist Tomogr 2024; 48:317-322. [PMID: 37876233 DOI: 10.1097/rct.0000000000001559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
OBJECTIVES The aims of the study are to explore the morphological changes of olfactory bulb (OB) and olfactory sulcus in COVID-19 patients with associated olfactory dysfunction (OD) by measuring the OB volume (OBV) and olfactory sulcus depth (OSD) and to compare the measurement values with those of healthy individuals. METHODS Between March 2020 and January 2022, 31 consecutive hospitalized patients with a diagnosis of COVID-19 with anosmia and hyposmia who underwent brain magnetic resonance imaging and 35 normosmic control individuals were retrospectively included in the study. Bilateral OBV and OSD were measured and shape of the OB was determined based on the consensus by a neuroradiologist and an otorrhynolaryngologist. RESULTS The mean measurements for the right and the left sides for OBV (38 ± 8.5 and 37.1 ± 8.4, respectively) and OSD (7.4 ± 0.1 and 7.4 ± 1.0 mm, respectively) were significantly lower in COVID-19 patients with OD than those in control group (for the right and the left sides mean OBV 56.3 ± 17.1 and 49.1 ± 13.5, respectively, and mean OSD 9.6 ± 0.8 and 9.4 ± 0.8 mm, respectively). Abnormally shaped OB (lobulated, rectangular, or atrophic) were higher in patient group than those of controls.For the optimal cutoff values, OBV showed sensitivity and specificity values of 90.32% and, 57.14%, for the right, and 87.1% and 62.86% for the left side, respectively (area under the curve, 0.819 and 0.780). Olfactory sulcus depth showed sensitivity and specificity values of 90.32% and 94.29%, for the right, and 96.77% and 85.71%, for the left side, respectively (area under the curve, 0.960 and 0.944). CONCLUSIONS Decrease in OBV and OSD measurements in COVID-19 patients with OD at the early chronic stage of the disease supports direct damage to olfactory neuronal pathways and may be used to monitor olfactory nerve renewal while returning back to normal function.
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Affiliation(s)
| | | | | | | | | | | | - Derya Seyman
- Infectious Diseases, Health Sciences University Antalya Training and Research Hospital, Antalya, Turkey
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Gunder N, Dörig P, Witt M, Welge-Lüssen A, Menzel S, Hummel T. Future therapeutic strategies for olfactory disorders: electrical stimulation, stem cell therapy, and transplantation of olfactory epithelium-an overview. HNO 2023; 71:35-43. [PMID: 36734997 PMCID: PMC9897160 DOI: 10.1007/s00106-022-01249-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2022] [Indexed: 02/04/2023]
Abstract
Olfactory disorders may be temporary or permanent and can have various causes. Currently, many COVID-19 patients report a reduced or complete loss of olfactory function. A wide range of treatment options have been investigated in the past, such as olfactory training, acupuncture, medical therapy, transcranial magnetic stimulation, or surgical excision of olfactory epithelium, e.g., in severe qualitative smell disorders. The development of a bioelectric nose, e.g., in connection with direct electrical stimulation or transplantation of olfactory epithelium or stem cells, represent treatment options of the future. The basis of these developments and the state of knowledge is discussed in the following work.
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Affiliation(s)
- N Gunder
- Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany.
| | - P Dörig
- Universitäts-HNO Klinik Basel, Basel, Switzerland
| | - M Witt
- Institut für Anatomie, Universitätsmedizin Rostock, Rostock, Germany
| | | | - S Menzel
- Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - T Hummel
- Klinik und Poliklinik für Hals-, Nasen- und Ohrenheilkunde, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
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Tan ZW, Toong PJ, Guarnera E, Berezovsky IN. Disrupted chromatin architecture in olfactory sensory neurons: looking for the link from COVID-19 infection to anosmia. Sci Rep 2023; 13:5906. [PMID: 37041182 PMCID: PMC10088727 DOI: 10.1038/s41598-023-32896-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 04/04/2023] [Indexed: 04/13/2023] Open
Abstract
We tackle here genomic mechanisms of a rapid onset and recovery from anosmia-a potential diagnostic indicator for early-stage COVID-19 infection. Based on previous observations on how olfactory receptor (OR) gene expression is regulated via chromatin structure in mice, we hypothesized that the disruption of the OR gene expression and, respectively, deficiency of the OR function can be caused by chromatin reorganization taking place upon SARS-CoV-2 infection. We obtained chromatin ensemble reconstructions from COVID-19 patients and control samples using our original computational framework for the whole-genome 3D chromatin ensemble reconstruction. Specifically, we used megabase-scale structural units and effective interactions between them obtained in the Markov State modelling of the Hi-C contact network as an unput in the stochastic embedding procedure of the whole-genome 3D chromatin ensemble reconstruction. We have also developed here a new procedure for analyzing fine structural hierarchy with (sub)TAD-size units in local chromatin regions, which we apply here to parts of chromosomes containing OR genes and corresponding regulatory elements. We observed structural modifications in COVID-19 patients on different levels of chromatin organization, from the alteration of whole genome structure and chromosomal intermingling to reorganization of contacts between chromatin loops at the level of topologically associating domains. While complementary data on known regulatory elements point to potential pathology-associated changes within the overall picture of chromatin alterations, further investigation using additional epigenetic factors mapped on 3D reconstructions with improved resolution will be required for better understanding of anosmia caused by SARS-CoV-2 infection.
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Affiliation(s)
- Zhen Wah Tan
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute (BII), 30 Biopolis Street, Matrix, Singapore, 138671, Republic of Singapore
| | - Ping Jing Toong
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute (BII), 30 Biopolis Street, Matrix, Singapore, 138671, Republic of Singapore
| | - Enrico Guarnera
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute (BII), 30 Biopolis Street, Matrix, Singapore, 138671, Republic of Singapore
- Computational Drug Discovery, EMD Serono Research and Development Institute, Merck KGaA, 45A Middlesex Tpke, Billerica, MA, 01821, USA
| | - Igor N Berezovsky
- Agency for Science, Technology and Research (A*STAR), Bioinformatics Institute (BII), 30 Biopolis Street, Matrix, Singapore, 138671, Republic of Singapore.
- Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, Singapore, 117597, Singapore.
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Hendawy E, El-Anwar MW, Elghamry RM, Abdallah AM, Ibrahim AM. Anosmia in COVID-19 Patients: Can We Predict the Severity of Chest Manifestations? Int Arch Otorhinolaryngol 2023; 27:e143-e151. [PMID: 36714889 PMCID: PMC9879642 DOI: 10.1055/s-0042-1758716] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 08/22/2022] [Indexed: 01/28/2023] Open
Abstract
Introduction Anosmia is one of the common symptoms of COVID-19, the link between severity of chest infection and anosmia was investigated by few studies. Objectives To find an association between anosmia and severity of chest infection. Methods An analysis of patients admitted to isolation hospital of our university with confirmed polymerase chain reaction positive testing for COVID-19, between March 2021 until September 2021. We called all patients who reported anosmia during their time of illness and asked them about anosmia. We examined their chest CT. A statistical analysis was done. Results A total of 140 patients completed the study; 65% were female and 56.4% had complete anosmia. Anosmia was significantly associated with loss of taste. Smell returned in 92.5% of anosmic patients. Duration of smell loss was ∼ 2 weeks in 40.5%. The most common symptoms associated with anosmia were running nose, sore throat, fever, and cough. Loss of smell was significantly associated with mild chest disease. 73.4% of anosmic patients had mild chest infection, 21.5% of them had moderate infection, and 5.1% had severe chest infection. Conclusion The pattern of anosmia in COVID-19 patients has some common similarities in general; the way it starts, the associated symptoms, the time until smell returns and, the most important, the severity of chest infection. As anosmia is significantly associated with mild chest infection. the presence of anosmia could be an independent predictor of good COVID-19 outcome as reflected by a lower disease severity and less frequent ICU admissions.
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Affiliation(s)
- Ehsan Hendawy
- Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine, Zagazig University, Zagazig, Egypt,Address for correspondence Ehsan Hendawy, MD Department of Otorhinolaryngology, Head-Neck SurgeryUniversity of Zagazig, Zagazig, Egypt, Postal Code: 44511
| | - Mohammad Waheed El-Anwar
- Department of Otorhinolaryngology, Head and Neck Surgery, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Reda M. Elghamry
- Department of Chest Disease, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Amany M. Abdallah
- Department of Family Medicine, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Amin M. Ibrahim
- Department of Diagnostic Radiology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
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Gavid M, Coulomb L, Thomas J, Aouimeur I, Verhoeven P, Mentek M, Dumollard JM, Forest F, Prades JM, Thuret G, Gain P, He Z. Technique of flat-mount immunostaining for mapping the olfactory epithelium and counting the olfactory sensory neurons. PLoS One 2023; 18:e0280497. [PMID: 36649285 PMCID: PMC9844923 DOI: 10.1371/journal.pone.0280497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 01/02/2023] [Indexed: 01/18/2023] Open
Abstract
The pathophysiology underlying olfactory dysfunction is still poorly understood, and more efficient biomolecular tools are necessary to explore this aspect. Immunohistochemistry (IHC) on cross sections is one of the major tools to study the olfactory epithelium (OE), but does not allow reliable counting of olfactory sensory neurons (OSNs) or cartography of the OE. In this study, we want to present an easy immunostaining technique to compensate for these defects of IHC. Using the rat model, we first validated and pre-screened the key OSN markers by IHC on cross sections of the OE. Tuj-1, OMP, DCX, PGP9.5, and N-cadherin were selected for immunostaining on flat-mounted OE because of their staining of OSN dendrites. A simple technique for immunostaining on flat-mounted septal OE was developed: fixation of the isolated septum mucosa in 0.5% paraformaldehyde (PFA) preceded by pretreatment of the rat head in 1% PFA for 1 hour. This technique allowed us to correctly reveal the olfactory areas using all the 5 selected markers on septum mucosa. By combining the mature OSN marker (OMP) and an immature OSN marker (Tuj-1), we quantified the mature (OMP+, Tuj-1-), immature (OMP-, Tuj-1+), transitory (OMP+, Tuj-1+) and total OSN density on septal OE. They were respectively 42080 ± 11820, 49384 ± 7134, 14448 ± 5865 and 105912 ± 13899 cells per mm2 (mean ± SD). Finally, the same immunostaining technique described above was performed with Tuj-1 for OE cartography on ethmoid turbinates without flat-mount.
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Affiliation(s)
- Marie Gavid
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
- Department of Otorhinolaryngology, CHU of Saint-Etienne, Saint-Etienne, France
| | - Louise Coulomb
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
| | - Justin Thomas
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
| | - Inès Aouimeur
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
| | - Paul Verhoeven
- CIRI, GIMAP Team, INSERM U1111, CNRS UMR5308, University of Lyon, University of Saint-Etienne, Saint-Etienne, France
| | - Marielle Mentek
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
| | - Jean-Marc Dumollard
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
- Department of Pathology, CHU of Saint-Etienne, Saint-Etienne, France
| | - Fabien Forest
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
- Department of Pathology, CHU of Saint-Etienne, Saint-Etienne, France
| | - Jean-Michel Prades
- Department of Otorhinolaryngology, CHU of Saint-Etienne, Saint-Etienne, France
| | - Gilles Thuret
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
| | - Philippe Gain
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
| | - Zhiguo He
- Laboratory BIIO (EA2521), Jean Monnet University, Saint-Etienne, France
- * E-mail:
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O'Byrne L, Webster KE, MacKeith S, Philpott C, Hopkins C, Burton MJ. Interventions for the treatment of persistent post-COVID-19 olfactory dysfunction. Cochrane Database Syst Rev 2022; 9:CD013876. [PMID: 36062970 PMCID: PMC9443431 DOI: 10.1002/14651858.cd013876.pub3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Olfactory dysfunction is a common consequence of COVID-19 infection and persistent symptoms can have a profound impact on quality of life. At present there is little guidance on how best to treat this condition. A variety of interventions have been suggested to promote recovery, including medication and olfactory training. However, it is uncertain whether any intervention is of benefit. This is an update of the 2021 review with one additional study added. OBJECTIVES: 1) To evaluate the benefits and harms of any intervention versus no treatment for people with persisting olfactory dysfunction due to COVID-19 infection. 2) To keep the evidence up-to-date, using a living systematic review approach. SEARCH METHODS: The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the latest search was 20 October 2021. SELECTION CRITERIA: We included randomised controlled trials (RCTs) in people with COVID-19 related olfactory disturbance that had persisted for at least four weeks. We included any intervention compared to no treatment or placebo. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were the recovery of sense of smell, disease-related quality of life and serious adverse effects. Secondary outcomes were the change in sense of smell, general quality of life, prevalence of parosmia and other adverse effects (including nosebleeds/bloody discharge). We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS We included two studies with 30 participants. The studies evaluated the following interventions: systemic corticosteroids plus intranasal corticosteroid/mucolytic/decongestant and palmitoylethanolamide plus luteolin. Systemic corticosteroids plus intranasal corticosteroid/mucolytic/decongestant compared to no intervention We included a single RCT with 18 participants who had anosmia for at least 30 days following COVID-19 infection. Participants received a 15-day course of oral corticosteroids combined with nasal irrigation (consisting of an intranasal corticosteroid/mucolytic/decongestant solution) or no intervention. Psychophysical testing was used to assess olfactory function at 40 days. This is a single, small study and for all outcomes the certainty of evidence was very low. We are unable to draw meaningful conclusions from the numerical results. Palmitoylethanolamide plus luteolin compared to no intervention We included a single RCT with 12 participants who had anosmia or hyposmia for at least 90 days following COVID-19 infection. Participants received a 30-day course of palmitoylethanolamide and luteolin or no intervention. Psychophysical testing was used to assess olfactory function at 30 days. This is a single, small study and for all outcomes the certainty of evidence was very low. We are unable to draw meaningful conclusions from the numerical results. AUTHORS' CONCLUSIONS There is very limited evidence available on the efficacy and harms of treatments for persistent olfactory dysfunction following COVID-19 infection. However, we have identified a number of ongoing trials in this area. As this is a living systematic review we will update the data regularly, as new results become available.
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Affiliation(s)
- Lisa O'Byrne
- Department of Otolaryngology Head and Neck Surgery, St Vincent's University Hospital, Dublin 4, Ireland
| | - Katie E Webster
- Cochrane ENT, Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Samuel MacKeith
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Carl Philpott
- Department of Medicine, Norwich Medical School, University of East Anglia, Norwich, UK
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Mendes Paranhos AC, Nazareth Dias ÁR, Machado da Silva LC, Vieira Hennemann Koury G, de Jesus Sousa E, Cerasi AJ, Souza GS, Simões Quaresma JA, Magno Falcão LF. Sociodemographic Characteristics and Comorbidities of Patients With Long COVID and Persistent Olfactory Dysfunction. JAMA Netw Open 2022; 5:e2230637. [PMID: 36074464 PMCID: PMC9459661 DOI: 10.1001/jamanetworkopen.2022.30637] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
IMPORTANCE Determining the characteristics, type, and severity of olfactory dysfunction in patients with long COVID is important for the prognosis and potential treatment of the affected population. OBJECTIVE To describe the sociodemographic and clinical features of patients with long COVID who develop persistent olfactory dysfunction. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study, conducted at a rehabilitation center at a public university in the Amazon region of Brazil between September 9, 2020, and October 20, 2021, comprised 219 patients with long COVID and self-reported neurologic symptoms. Of these 219 patients, 139 received a diagnosis of chronic olfactory dysfunction, as confirmed by the Connecticut Chemosensory Clinical Research Center (CCCRC) test. EXPOSURE Clinical diagnosis of long COVID. MAIN OUTCOMES AND MEASURES Electronic case report forms were prepared for the collection of sociodemographic and clinical data. Patients' sense of smell was evaluated via a CCCRC test, and the association of olfactory dysfunction with aspects of daily life was recorded using a questionnaire. RESULTS Of the 219 patients included in the study, 164 (74.9%) were women, 194 (88.6%) were between 18 and 59 years of age (mean [SD] age, 43.2 [12.9] years), 206 (94.1%) had more than 9 years of education, and 115 (52.5%) had a monthly income of up to US $192.00. In the study group, 139 patients (63.5%) had some degree of olfactory dysfunction, whereas 80 patients (36.5%) had normosmia. Patients with olfactory dysfunction had a significantly longer duration of long COVID symptoms than those in the normosmia group (mean [SD], 242.7 [101.9] vs 221.0 [97.5] days; P = .01). Among patients with anosmia, there was a significant association between olfactory dysfunction and daily activities, especially in terms of impairment in hazard detection (21 of 31 patients [67.7%]), personal hygiene (21 of 31 patients [67.7%]), and food intake (21 of 31 patients [67.7%]). Univariable logistic regression analyses found that ageusia symptoms were associated with the occurrence of olfactory dysfunction (odds ratio [OR], 11.14 [95% CI, 4.76-26.07]; P < .001), whereas headache (OR, 0.41 [95% CI, 0.22-0.76]; P < .001) and sleep disorders (OR, 0.48 [95% CI, 0.26-0.92]; P = .02) showed an inverse association with the occurrence of olfactory dysfunction. CONCLUSIONS AND RELEVANCE Olfactory dysfunction is one of the most important long-term neurologic symptoms of COVID-19, with the highest prevalence seen among women, adults, and outpatients. Patients with olfactory dysfunction may experience persistent severe hyposmia or anosmia more than 1 year from the onset of symptoms, suggesting the possibility of the condition becoming a permanent sequela.
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Affiliation(s)
- Alna Carolina Mendes Paranhos
- Tropical Medicine Center, Federal University of Pará, Belém, Brazil
- Biological and Health Center, Pará State University, Belém, Brazil
| | | | | | | | | | - Antônio José Cerasi
- Biological Science Center, Federal University of Pará, Belém, Brazil
- Cosmopolita College, Belém, Brazil
| | - Givago Silva Souza
- Tropical Medicine Center, Federal University of Pará, Belém, Brazil
- Biological Science Center, Federal University of Pará, Belém, Brazil
| | - Juarez Antônio Simões Quaresma
- Tropical Medicine Center, Federal University of Pará, Belém, Brazil
- Biological and Health Center, Pará State University, Belém, Brazil
| | - Luiz Fábio Magno Falcão
- Biological and Health Center, Pará State University, Belém, Brazil
- University of São Paulo, São Paulo, Brazil
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Ueha R, Ito T, Furukawa R, Kitabatake M, Ouji-Sageshima N, Ueha S, Koyama M, Uranaka T, Kondo K, Yamasoba T. Oral SARS-CoV-2 Inoculation Causes Nasal Viral Infection Leading to Olfactory Bulb Infection: An Experimental Study. Front Cell Infect Microbiol 2022; 12:924725. [PMID: 35770069 PMCID: PMC9234459 DOI: 10.3389/fcimb.2022.924725] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 05/19/2022] [Indexed: 12/26/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections can cause long-lasting anosmia, but the impact of SARS-CoV-2 infection, which can spread to the nasal cavity via the oral route, on the olfactory receptor neuron (ORN) lineage and olfactory bulb (OB) remains undetermined. Using Syrian hamsters, we explored whether oral SARS-CoV-2 inoculation can lead to nasal viral infection, examined how SARS-CoV-2 affects the ORN lineage by site, and investigated whether SARS-CoV-2 infection can spread to the OB and induce inflammation. On post-inoculation day 7, SARS-CoV-2 presence was confirmed in the lateral area (OCAM-positive) but not the nasal septum of NQO1-positive and OCAM-positive areas. The virus was observed partially infiltrating the olfactory epithelium, and ORN progenitor cells, immature ORNs, and mature ORNs were fewer than in controls. The virus was found in the olfactory nerve bundles to the OB, suggesting the nasal cavity as a route for SARS-CoV-2 brain infection. We demonstrated that transoral SARS-CoV-2 infection can spread from the nasal cavity to the central nervous system and the possibility of central olfactory dysfunction due to SARS-CoV-2 infection. The virus was localized at the infection site and could damage all ORN-lineage cells.
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Affiliation(s)
- Rumi Ueha
- Swallowing Center, the University of Tokyo Hospital, Tokyo, Japan
- Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, the University of Tokyo, Tokyo, Japan
- *Correspondence: Rumi Ueha, ;
| | - Toshihiro Ito
- Department of Immunology, Nara Medical University, Nara, Japan
| | | | | | | | - Satoshi Ueha
- Division of Molecular Regulation of Inflammatory and Immune Diseases, Research Institute for Biomedical Sciences, Tokyo University of Science, Chiba, Japan
| | - Misaki Koyama
- Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, the University of Tokyo, Tokyo, Japan
| | - Tsukasa Uranaka
- Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, the University of Tokyo, Tokyo, Japan
| | - Kenji Kondo
- Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, the University of Tokyo, Tokyo, Japan
| | - Tatsuya Yamasoba
- Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, the University of Tokyo, Tokyo, Japan
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10
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Maamar M, Artime A, Pariente E, Fierro P, Ruiz Y, Gutiérrez S, Tobalina M, Díaz-Salazar S, Ramos C, Olmos JM, Hernández JL. Post-COVID-19 syndrome, low-grade inflammation and inflammatory markers: a cross-sectional study. Curr Med Res Opin 2022; 38:901-909. [PMID: 35166141 PMCID: PMC8935459 DOI: 10.1080/03007995.2022.2042991] [Citation(s) in RCA: 58] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Post-COVID syndrome (PCS) is a poorly known entity. An underlying chronic, low-grade inflammation (LGI) has been theorized as a pathophysiological mechanism. Available data on biomarkers in PCS show conflicting results. Our aim was to know whether subjects with PCS present higher levels of inflammatory markers, after a mild COVID-19. METHODS Analytical cross-sectional study. Cases of mild COVID-19 in a community setting were included. We collected epidemiological data (age, sex, BMI, smoking, comorbidities), variables of the acute COVID-19 (duration, symptoms), and data at 3 months after the acute phase (symptoms and laboratory test). Serum C-reactive protein (CRP), neutrophil and lymphocyte counts, neutrophil/lymphocyte ratio (NLR), lactate dehydrogenase, ferritin, fibrinogen, and D-dimer levels were analysed. LGI was defined as CRP >0.3 and <1.0 mg/dL. A subject was classified as PCS + if presented signs and symptoms >12 weeks after an infection consistent with COVID-19. Five composite indices (C1-C5) were developed, combining the upper ranges of biomarkers distributions. Multivariate analyses were performed. RESULTS We analysed 121 mild COVID-19 cases (mean age = 45.7 years, 56.2% women). Among the acute symptoms, women presented a higher frequency of fatigue (54.4% vs 30.2%; p = .008). PCS affected 35.8% of women and 20.8% of men (p = .07), and the most reported symptoms were fatigue (42.8%), anosmia (40%), ageusia (22.8%), dyspnea (17.1%) and myalgia (11.4%). Neutrophil count, NLR, CRP and fibrinogen showed the best correlations with PCS and were selected to develop the indices. In women PCS+, C1, C3 and C4 indices were more frequently met, while in men PCS+, C2, C5 and CRP were in the range of LGI. Anosmia, ageusia and fatigue were related to higher neutrophil counts, with sex differences. Fibrinogen levels were higher in persistent myalgia (510 ± 82 mg/dL vs 394 ± 87; p = .013). In multivariable analysis, a woman with a neutrophil count above the median, or with fibrinogen level or NLR in the highest tertile, had a 4-5-fold increased risk of prevalent PCS. A man with CRP in the range of LGI, or fibrinogen level or a neutrophil count in the highest tertile, had a 10-17-fold increased risk of prevalent PCS. CONCLUSIONS The data obtained in the present cross-sectional study seems to demonstrate a consistent association between PCS and upper ranges of the neutrophil count, NLR, fibrinogen, and CRP in the LGI range. Furthermore, composite indices appear useful in detecting relationships between slight elevations of biomarkers and PCS, and our study identifies relevant sex differences in symptoms and markers regarding the PCS.
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Affiliation(s)
- Meryam Maamar
- Emergency Service. Osakidetza, Servicio Vasco de Salud, Bilbao, País Vasco, Spain
| | - Arancha Artime
- El Llano - Primary Health Care Center, SESPA - Servicio Asturiano de Salud, Gijón Asturias, Spain
| | - Emilio Pariente
- Camargo Interior - Primary Health Care Center, Servicio Cántabro de Salud, Muriedas, Cantabria, Spain
- Depto. de Medicina y Psiquiatría, Universidad de Cantabria, Santander, Cantabria, Spain
- CONTACT Emilio Pariente “Camargo Interior” Primary Care Center, Associate Professor, University of Cantabria, Avda Bilbao, s/n. 39600-Muriedas, Cantabria, Spain
| | - Patricia Fierro
- Camargo Interior - Primary Health Care Center, Servicio Cántabro de Salud, Muriedas, Cantabria, Spain
| | - Yolanda Ruiz
- Camargo Interior - Primary Health Care Center, Servicio Cántabro de Salud, Muriedas, Cantabria, Spain
| | - Silvia Gutiérrez
- Camargo Interior - Primary Health Care Center, Servicio Cántabro de Salud, Muriedas, Cantabria, Spain
| | - Marian Tobalina
- Camargo Interior - Primary Health Care Center, Servicio Cántabro de Salud, Muriedas, Cantabria, Spain
| | - Sara Díaz-Salazar
- Camargo Interior - Primary Health Care Center, Servicio Cántabro de Salud, Muriedas, Cantabria, Spain
| | - Carmen Ramos
- Depto. de Medicina y Psiquiatría, Universidad de Cantabria, Santander, Cantabria, Spain
- Camargo Costa - Primary Health Care Center, Servicio Cántabro de Salud, Maliaño, Cantabria, Spain
| | - José M. Olmos
- Depto. de Medicina y Psiquiatría, Universidad de Cantabria, Santander, Cantabria, Spain
- Servicio de Medicina Interna, Hospital Universitario Marqués de Valdecilla, Instituto de Investigación Valdecilla (IDIVAL), Santander, Cantabria, Spain
| | - José L. Hernández
- Depto. de Medicina y Psiquiatría, Universidad de Cantabria, Santander, Cantabria, Spain
- Servicio de Medicina Interna, Hospital Universitario Marqués de Valdecilla, Instituto de Investigación Valdecilla (IDIVAL), Santander, Cantabria, Spain
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11
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Patel R, Fang CH, Grube JG, Eloy JA, Hsueh WD. COVID-19 and rhinological surgery. OPERATIVE TECHNIQUES IN OTOLARYNGOLOGY--HEAD AND NECK SURGERY 2022; 33:103-111. [PMID: 35502266 PMCID: PMC9046134 DOI: 10.1016/j.otot.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The Coronavirus-19 (COVID-19) pandemic has caused disruptions in the normal patient care workflow, necessitating adaptations within the healthcare profession. The objective of this article is to outline some of these adaptations and considerations necessitated by COVID-19 within the subspeciality of rhinology and endoscopic skull base surgery.
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Affiliation(s)
- Rushi Patel
- Department of Otolaryngology - Head and Neck Surgery, Rutgers New Jersey Medical School, Newark, New Jersey
| | - Christina H Fang
- Department of Otorhinolaryngology - Head and Neck Surgery, Montefiore Medical Center, The University Hospital for Albert Einstein College of Medicine, Bronx, New York
| | - Jordon G Grube
- Division of Otolaryngology, Albany Medical College, Albany, New York
| | - Jean Anderson Eloy
- Department of Otolaryngology - Head and Neck Surgery, Rutgers New Jersey Medical School, Newark, New Jersey
- Center for Skull Base and Pituitary Surgery, Neurological Institute of New Jersey, Rutgers New Jersey Medical School, Newark, New Jersey
- Department of Neurological Surgery, Rutgers New Jersey Medical School, Newark, New Jersey
- Department of Ophthalmology and Visual Science, Rutgers New Jersey Medical School, Newark, New Jersey
- Department of Otolaryngology and Facial Plastic Surgery, Saint Barnabas Medical Center - RWJ Barnabas Health, Livingston, New Jersey
| | - Wayne D Hsueh
- Department of Otolaryngology - Head and Neck Surgery, Rutgers New Jersey Medical School, Newark, New Jersey
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12
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Frequency and Severity of Ear-Nose-Throat (ENT) Symptoms during COVID-19 Infection. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58050623. [PMID: 35630040 PMCID: PMC9143391 DOI: 10.3390/medicina58050623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 04/24/2022] [Accepted: 04/28/2022] [Indexed: 11/17/2022]
Abstract
Background and Objectives: Coronavirus disease 2019 (COVID-19) is a new disease entity caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The main symptoms of infection at the onset of the pandemic include dyspnea, cough and high fever. Ear−nose−throat (ENT) symptoms are among the ones presented by patients in the course of infection. The aim of the study was to analyze the frequency of ENT symptoms and to assess their severity and duration in COVID-19 patients. Materials and Methods: The study included 337 patients who had been infected with SARS-CoV-2, as confirmed by a PCR test. The study participants were >18 years old; the mean age was 43.98 years ± 13.47 SD. The convalescents completed a questionnaire that contained 26 questions, including 9 detailed questions related to ENT symptoms, such as sore throat, vertigo, dizziness, hearing disorders, olfactory disorders, taste disturbance, headache, cough and dyspnea. The severity of symptoms was assessed using a Visual Analogue Scale (VAS). Results: The most reported ENT symptoms were olfactory disorders, which occurred in 72% of patients. The second most frequent symptom was taste disturbance (68%), VAS = 6.79 ± 3.01. Vertigo and dizziness were reported by 34% of respondents (VAS = 4.01 ± 2.01). Tinnitus was observed in 15% of patients, VAS = 3.87 ± 1.98; 14% of the subjects reported hearing impairment (VAS = 3.81 ± 2.37). Conclusions: Symptoms related to the sense of smell, taste and hearing are some of the most common symptoms in the course of COVID-19, which is important in the therapeutic and epidemiological management of patients. Delayed diagnosis and treatment of symptoms, especially those related to the hearing organ, may result in greater permanent damage.
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13
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Ziuzia-Januszewska L, Januszewski M. Pathogenesis of Olfactory Disorders in COVID-19. Brain Sci 2022; 12:brainsci12040449. [PMID: 35447981 PMCID: PMC9029941 DOI: 10.3390/brainsci12040449] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 03/09/2022] [Accepted: 03/23/2022] [Indexed: 12/11/2022] Open
Abstract
Since the outbreak of the SARS-CoV-2 pandemic, olfactory disorders have been reported as a frequent symptom of COVID-19; however, its pathogenesis is still debated. The aim of this review is to summarize the current understanding of the pathogenesis of smell impairment in the course of COVID-19 and to highlight potential avenues for future research on this issue. Several theories have been proposed to explain the pathogenesis of COVID-19-related anosmia, including nasal obstruction and rhinorrhea, oedema of the olfactory cleft mucosa, olfactory epithelial damage either within the olfactory receptor cells or the supporting non-neural cells (either direct or immune-mediated), damage to the olfactory bulb, and impairment of the central olfactory pathways. Although the pathogenesis of COVID-19-related anosmia is still not fully elucidated, it appears to be mainly due to sensorineural damage, with infection of the olfactory epithelium support cells via the ACE1 receptor and disruption of the OE caused by immense inflammatory reaction, and possibly with direct olfactory sensory neurons infection mediated by the NRP-1 receptor. Involvement of the higher olfactory pathways and a conductive component of olfactory disorders, as well as genetic factors, may also be considered.
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Affiliation(s)
- Laura Ziuzia-Januszewska
- Department of Otolaryngology, Central Clinical Hospital, Ministry of Interior and Administration, 02-507 Warsaw, Poland
- Correspondence: or ; Tel.: +48-477221182
| | - Marcin Januszewski
- Department of Obstetrics and Gynecology, Central Clinical Hospital, Ministry of Interior and Administration, 02-507 Warsaw, Poland;
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14
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Aldundag A, Yilmaz E, Kesimli MC. Modified Olfactory Training Is an Effective Treatment Method for COVID-19 Induced Parosmia. Laryngoscope 2022; 132:1433-1438. [PMID: 35257391 PMCID: PMC9088368 DOI: 10.1002/lary.30101] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 02/12/2022] [Accepted: 02/28/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVES Coronavirus disease (COVID-19) infection often causes olfactory dysfunction and parosmia may occur in some patients with olfactory dysfunction. In this study, we retrospectively investigated the effectiveness of modified olfactory training (MOT) for the treatment of COVID-19-induced parosmia. STUDY DESIGN This study presents results of MOT performed with 12 odors for 36 weeks in patients with olfactory dysfunction following COVID-19 infection. A total of 75 participants were included in the study (mean age 33 years, range 16-60 years). METHODS The patients were separated into two groups: 1) Treatment group consisted of parosmia patients who received MOT with three sets of four different odors sequentially. 2) Control group consisted of parosmia patients who did not perform any olfactory training. Both groups were matched for age and sex distribution of participants. TDI scores were compared at the time of application and at the end of the 9th month by the Sniffin' Sticks Test. The results of the 0th and 9th months were recorded by applying the parosmia assessment scale to both groups. The results were analyzed statistically, and p < 0.05 was considered significant. RESULTS When the treatment group and the control group were compared, a significant improvement was observed in both groups at the third, sixth, and ninth month, however the improvement in the treatment group was found to be better than in the control group (P < .001). Extending the treatment from 6 to 9 months in the treatment group was found to be effective in mitigating parosmia complaints and improving discrimination scores (P < .001). CONCLUSION This study has shown that modified olfactory training is effective in the treatment of parosmia following COVID-19 infection. LEVEL OF EVIDENCE 3 Laryngoscope, 2022.
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Affiliation(s)
- Aytug Aldundag
- Department of Otolaryngology, Head and Neck Surgery, Biruni University School of Medicine, Istanbul, Turkey
| | - Eren Yilmaz
- Faculty of Health Sciences, Istanbul Gelisim University, Istanbul, Turkey
| | - Mustafa Caner Kesimli
- Department of Otolaryngology, Head and Neck Surgery, Istinye University School of Medicine, Istanbul, Turkey
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15
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Alfallaj R, AlSkait G, Alamari N, Alfawzan L, Abualgasem M, Alotaibi NH, Sumaily I, Alarifi I, Alsaleh S. Incidence of Olfactory Dysfunction in Patients with COVID-19 in a Tertiary Hospital in Saudi Arabia. ALLERGY & RHINOLOGY (PROVIDENCE, R.I.) 2022; 13:21526575221140809. [PMID: 36452479 PMCID: PMC9703475 DOI: 10.1177/21526575221140809] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
BACKGROUND Coronavirus disease (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2, a novel virus that emerged in China in December 2019. In many cases of COVID-19, olfactory dysfunction (OD) is the only symptom. OBJECTIVES This study aimed to examine the incidence of OD in patients with COVID-19 and identify an association between OD and COVID-19-related morbidity and admission. DESIGN This was a cross-sectional study. METHODS Real-time reverse transcription polymerase chain reaction-confirmed cases of COVID-19 from the Security Forces Hospital electronic registry from June 2020 to September 2020 were included in our study. Data on medical background, severity of the disease, and other related factors were collected through phone calls and electronic healthcare systems and analyzed to investigate OD in the participants. RESULTS Of the participants, 68% had OD, with a mean recovery time of 18 days and a mean follow-up time of 129 days (76-211 days). OD was negatively correlated with admission and morbidity. CONCLUSION OD is a common presentation of COVID-19 and is more prevalent in mild cases of infection.
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Affiliation(s)
- Rayan Alfallaj
- Otolaryngology—Head & Neck Surgery Department, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Ghada AlSkait
- College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Nouf Alamari
- College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Lama Alfawzan
- College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | | | - Naif H. Alotaibi
- ENT Department, King Faisal Specialist Hospital, Riyadh, Saudi Arabia
| | - Ibrahim Sumaily
- ENT Department, King Fahd Central Hospital, Jazan, Saudi Arabia
| | - Ibrahim Alarifi
- ENT Department, Security Forces Hospital, Riyadh, Saudi Arabia
| | - Saad Alsaleh
- Otolaryngology—Head & Neck Surgery Department, College of Medicine, King Saud University, Riyadh, Saudi Arabia
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16
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Delayed recovery from Sars-CoV-2-related anosmia predicts incomplete olfactory restoration. The Journal of Laryngology & Otology 2021; 136:237-242. [PMID: 34895368 DOI: 10.1017/s0022215121004047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Mele D, Calastri A, Maiorano E, Cerino A, Sachs M, Oliviero B, Mantovani S, Baldanti F, Bruno R, Benazzo M, Grifoni A, Sette A, Mondelli MU, Varchetta S. High Frequencies of Functional Virus-Specific CD4 + T Cells in SARS-CoV-2 Subjects With Olfactory and Taste Disorders. Front Immunol 2021; 12:748881. [PMID: 34858405 PMCID: PMC8631501 DOI: 10.3389/fimmu.2021.748881] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/20/2021] [Indexed: 12/22/2022] Open
Abstract
Olfactory and taste disorders (OTD) are commonly found as presenting symptoms of SARS-CoV-2 infection in patients with clinically mild COVID-19. Virus-specific T cells are thought to play an important role in the clearance of SARS-CoV-2; therefore the study of T cell specific immune responses in patients with mild symptoms may help to understand their possible role in protection from severe disease. We evaluated SARS-CoV-2-specific T cell responses to four different peptide megapools covering all SARS-CoV-2 proteins during the acute phase of the disease in 33 individuals with mild or no other symptom beside OTD and in 22 age-matched patients with severe infection. A control group of 15 outpatients with OTD and consistently negative nasopharyngeal SARS-CoV-2 RNA swabs and virus-specific IgG serology was included in the study. Increased frequencies of virus-specific CD4+ and CD8+ T cells were found in SARS-CoV-2 positive patients with OTD compared with those with severe COVID-19 and with SARS-CoV-2 negative OTD individuals. Moreover, enhanced CD4+ and CD8+ T-cell activation induced by SARS-CoV-2 peptides was associated with higher interferon (IFN)γ production. Increased frequencies of Spike (S1/S2)-specific CD4+ T cells showing enhanced IFNγ secretion and granzyme B content were associated with serum spike-specific IgG in the OTD group. In conclusion, patients with SARS-CoV-2 induced OTD develop highly functional virus-specific CD4+ and CD8+ T cells during the symptomatic phase of the disease, suggesting that robust and coordinated T-cell responses provide protection against extension of COVID-19 to the lower respiratory tract.
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Affiliation(s)
- Dalila Mele
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Anna Calastri
- Division of Otorhinolaryngology, Department of Surgery, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Eugenia Maiorano
- Division of Otorhinolaryngology, Department of Surgery, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Antonella Cerino
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Michele Sachs
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.,Division of Infectious Diseases I, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Barbara Oliviero
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Stefania Mantovani
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Fausto Baldanti
- Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy.,Division of Virology and Microbiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Raffaele Bruno
- Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy.,Division of Infectious Diseases I, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Marco Benazzo
- Division of Otorhinolaryngology, Department of Surgery, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.,Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy
| | - Alba Grifoni
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, United States
| | - Alessandro Sette
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, United States.,Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California, San Diego, La Jolla, CA, United States
| | - Mario U Mondelli
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.,Department of Internal Medicine and Therapeutics, University of Pavia, Pavia, Italy
| | - Stefania Varchetta
- Division of Clinical Immunology and Infectious Diseases, Department of Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
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18
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Neurological Manifestations and Outcomes in a Retrospective Cohort of Mexican Inpatients with SARS-CoV-2 Pneumonia: Design of a Risk Profile. Healthcare (Basel) 2021; 9:healthcare9111501. [PMID: 34828547 PMCID: PMC8620259 DOI: 10.3390/healthcare9111501] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 01/08/2023] Open
Abstract
We analyzed the neurological manifestations in Mexican patients hospitalized with pneumonia due to COVID-19 and investigated the association between demographic, clinical, and biochemical variables and outcomes, including death. A retrospective, analytical study was conducted using the electronic records of patients hospitalized between 1 April 2020 and 30 September 2020. Records of 1040 patients were analyzed: 31.25% died and 79.42% had neurological symptoms, including headache (80.62%), anosmia (32.20%), ageusia (31.96%), myopathy (28.08%), disorientation (14.89%), encephalopathy (12.22%), neuropathy (5.4%), stroke (1.3%), seizures (1.3%), cerebral hemorrhage (1.08%), encephalitis (0.84%), central venous thrombosis (0.36%), and subarachnoid hemorrhage (0.24%). Patients also had comorbidities, such as hypertension (42.30%), diabetes mellitus (38.74%), obesity (61.34%), chronic obstructive pulmonary disease (3.17%), and asthma (2.01%). Factors associated with neurological symptoms were dyspnea, chronic obstructive pulmonary disease, advanced respiratory support, prolonged hospitalization, and worsening fibrinogen levels. Factors associated with death were older age, advanced respiratory support, amine management, chronic obstructive pulmonary disease, intensive care unit management, dyspnea, disorientation, encephalopathy, hypertension, neuropathy, diabetes, male sex, three or more neurological symptoms, and obesity grade 3. In this study we designed a profile to help predict patients at higher risk of developing neurological complications and death following COVID-19 infection.
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19
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Najafloo R, Majidi J, Asghari A, Aleemardani M, Kamrava SK, Simorgh S, Seifalian A, Bagher Z, Seifalian AM. Mechanism of Anosmia Caused by Symptoms of COVID-19 and Emerging Treatments. ACS Chem Neurosci 2021; 12:3795-3805. [PMID: 34609841 PMCID: PMC8507153 DOI: 10.1021/acschemneuro.1c00477] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/20/2021] [Indexed: 01/08/2023] Open
Abstract
The occurrence of anosmia, the loss or change in sense of smell, is one of the most common symptoms of COVID-19 experienced by almost 53% of those affected. Several hypotheses explain the mechanism of anosmia in patients suffering from COVID-19. This study aims to review the related mechanisms and answer the questions regarding COVID-19-related anosmia as well as propose a new strategy for treatment of long-term anosmia as a result of COVID-19 infection. This paper covers all of the studies investigating olfactory disorders following COVID-19 infection and explains the possible reasons for the correlated anosmia, including olfactory cleft syndrome, local inflammation in the nasal epithelium, early apoptosis of olfactory cells, changes in olfactory cilia and odor transmission, damage to microglial cells, effect on olfactory bulbs, epithelial olfactory injury, and impairment of olfactory neurons and stem cells. The key questions that arise in this field have been discussed, such as why prevalent anosmia is varied among the age categories and among sexes and the correlation of anosmia with mild or severe COVID-19 infection. The angiotensin-converting enzyme 2 receptor is a significant player in the mechanism of anosmia in COVID-19 patients. Based on current studies, a novel approach to treat long-COVID-19 with ongoing anosmia has been proposed. The fields of smart drug delivery, tissue engineering, and cell therapy provide a hypothesized strategy that can minimize the side effects of current treatments and support efficient recovery of the olfactory system.
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Affiliation(s)
- Raziyeh Najafloo
- Department
of Tissue Engineering & Regenerative Medicine, Faculty of Advanced
Technologies in Medicine, Iran University
of Medical Sciences (IUMS), Tehran 1449614535, Iran
| | - Jila Majidi
- Department
of Tissue Engineering & Regenerative Medicine, Faculty of Advanced
Technologies in Medicine, Iran University
of Medical Sciences (IUMS), Tehran 1449614535, Iran
| | - Alimohamad Asghari
- Skull
Base Research Center, Hazrat Rasoul Akram Hospital, The Five Senses
Health Institute, Iran University of Medical
Sciences (IUMS), Tehran 1445613131, Iran
| | - Mina Aleemardani
- Biomaterials
and Tissue Engineering Group, Department of Materials Science and
Engineering, Kroto Research Institute, The
University of Sheffield, Sheffield S3 7HQ, United Kingdom
| | - Seyed Kamran Kamrava
- ENT
and Head and Neck Research Center and Department, Hazrat Rasoul Akram
Hospital, The Five Senses Health Institute, Iran University of Medical Sciences (IUMS), Tehran 1445613131, Iran
| | - Sara Simorgh
- Department
of Tissue Engineering & Regenerative Medicine, Faculty of Advanced
Technologies in Medicine, Iran University
of Medical Sciences (IUMS), Tehran 1449614535, Iran
| | - Amelia Seifalian
- University
College London Medical School (UCL), London WC1E 6BT, United
Kingdom
- Watford
General Hospital, Watford WD18 0HB, United Kingdom
| | - Zohreh Bagher
- Department
of Tissue Engineering & Regenerative Medicine, Faculty of Advanced
Technologies in Medicine, Iran University
of Medical Sciences (IUMS), Tehran 1449614535, Iran
- ENT
and Head and Neck Research Center and Department, Hazrat Rasoul Akram
Hospital, The Five Senses Health Institute, Iran University of Medical Sciences (IUMS), Tehran 1445613131, Iran
| | - Alexander M. Seifalian
- Nanotechnology
and Regenerative Medicine Commercialisation Centre (NanoRegMed Ltd.), London BioScience Innovation Centre, London NW1 0NH, United Kingdom
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20
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Pokharel S, Tamang S, Pokharel S, Mahaseth RK. Sudden sensorineural hearing loss in a post-COVID-19 patient. Clin Case Rep 2021; 9:e04956. [PMID: 34703602 PMCID: PMC8520694 DOI: 10.1002/ccr3.4956] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/02/2021] [Accepted: 09/25/2021] [Indexed: 12/23/2022] Open
Abstract
A detailed history and diagnostic evaluation for recent or past COVID-19 infection is vital in patients presenting with Sudden Sensorineural Hearing Loss (SSNHL) since SSNHL could be a sequelae of COVID-19 and timely diagnosis and intervention could significantly improve hearing and quality of life.
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Affiliation(s)
- Santoshi Pokharel
- College of MedicineNepalese Army Institute of Health SciencesKathmanduNepal
| | - Sumita Tamang
- College of MedicineNepalese Army Institute of Health SciencesKathmanduNepal
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21
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Vu DL, Martinez-Murillo P, Pigny F, Vono M, Meyer B, Eberhardt CS, Lemeille S, Von Dach E, Blanchard-Rohner G, Eckerle I, Huttner A, Siegrist CA, Kaiser L, Didierlaurent AM. Longitudinal Analysis of Inflammatory Response to SARS-CoV-2 in the Upper Respiratory Tract Reveals an Association with Viral Load, Independent of Symptoms. J Clin Immunol 2021; 41:1723-1732. [PMID: 34581925 PMCID: PMC8476983 DOI: 10.1007/s10875-021-01134-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 09/05/2021] [Indexed: 12/23/2022]
Abstract
Background SARS-CoV-2 infection leads to high viral loads in the upper respiratory tract that may be determinant in virus dissemination. The extent of intranasal antiviral response in relation to symptoms is unknown. Understanding how local innate responses control virus is key in the development of therapeutic approaches. Methods SARS-CoV-2-infected patients were enrolled in an observational study conducted at the Geneva University Hospitals, Switzerland, investigating virological and immunological characteristics. Nasal wash and serum specimens from a subset of patients were collected to measure viral load, IgA specific for the S1 domain of the spike protein, and a cytokine panel at different time points after infection; cytokine levels were analyzed in relation to symptoms. Results Samples from 13 SARS-CoV-2-infected patients and six controls were analyzed. We found an increase in CXCL10 and IL-6, whose levels remained elevated for up to 3 weeks after symptom onset. SARS-CoV-2 infection also induced CCL2 and GM-CSF, suggesting local recruitment and activation of myeloid cells. Local cytokine levels correlated with viral load but not with serum cytokine levels, nor with specific symptoms, including anosmia. Some patients had S1-specific IgA in the nasal cavity while almost none had IgG. Conclusion The nasal epithelium is an active site of cytokine response against SARS-CoV-2 that can last more than 2 weeks; in this mild COVID-19 cohort, anosmia was not associated with increases in any locally produced cytokines. Supplementary Information The online version contains supplementary material available at 10.1007/s10875-021-01134-z.
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Affiliation(s)
- Diem-Lan Vu
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland.
- Laboratory of Virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland.
- University of Geneva Medical School, Geneva, Switzerland.
| | - Paola Martinez-Murillo
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Fiona Pigny
- Laboratory of Virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
- University of Geneva Medical School, Geneva, Switzerland
| | - Maria Vono
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Benjamin Meyer
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Christiane S Eberhardt
- University of Geneva Medical School, Geneva, Switzerland
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Sylvain Lemeille
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Elodie Von Dach
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
- University of Geneva Medical School, Geneva, Switzerland
| | - Géraldine Blanchard-Rohner
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
- Unit of Immunology and Vaccinology, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland
| | - Isabella Eckerle
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
- Laboratory of Virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
- Geneva Centre for Emerging Viral Diseases, Geneva University Hospitals, Geneva, Switzerland
- Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Angela Huttner
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
- University of Geneva Medical School, Geneva, Switzerland
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Claire-Anne Siegrist
- University of Geneva Medical School, Geneva, Switzerland
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland
| | - Laurent Kaiser
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
- Laboratory of Virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
- University of Geneva Medical School, Geneva, Switzerland
- Geneva Centre for Emerging Viral Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Arnaud M Didierlaurent
- Department of Pathology and Immunology, Faculty of Medicine, Center of Vaccinology, University of Geneva, Geneva, Switzerland.
- Geneva Centre for Emerging Viral Diseases, Geneva University Hospitals, Geneva, Switzerland.
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22
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Quantitative but not qualitative flavor recognition impairments in COVID-19 patients. Ir J Med Sci 2021; 191:1759-1766. [PMID: 34562193 PMCID: PMC8475319 DOI: 10.1007/s11845-021-02786-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 09/12/2021] [Indexed: 11/24/2022]
Abstract
Background Smell and taste dysfunctions (STDs) are symptoms associated with COVID-19 syndrome, even if their incidence is still uncertain and variable. Aims In this study, the effects of SARS-CoV-2 infection on chemosensory function have been investigated using both a self-reporting questionnaire on smell and flavor perception, and a simplified flavor test. Methods A total of 111 subjects (19 hospitalized [HOS] and 37 home-isolated [HI] COVID-19 patients, and 55 healthy controls [CTRL]) were enrolled in the study. They received a self-evaluation questionnaire and a self-administered flavor test kit. The flavor test used consists in the self-administration of four solutions with a pure olfactory stimulus (coffee), a mixed olfactory-trigeminal stimulus (peppermint), and a complex chemical mixture (banana). Results After SARS-CoV-2 infection, HOS and HI patients reported similar prevalence of STDs, with a significant reduction of both smell and flavor self-estimated perception. The aromas of the flavor test were recognized by HI and HOS COVID-19 patients similarly to CTRL; however, the intensity of the perceived aromas was significantly lower in patients compared to controls. Conclusion Data reported here suggests that a chemosensory impairment is present after SARS-CoV-2 infection, and the modified “flavor test” could be a novel self-administering objective screening test to assess STDs in COVID-19 patients. Clinical trial registration no. NCT04840966; April 12, 2021, retrospectively registered Supplementary Information The online version contains supplementary material available at 10.1007/s11845-021-02786-x.
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23
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Webster KE, O'Byrne L, MacKeith S, Philpott C, Hopkins C, Burton MJ. Interventions for the prevention of persistent post-COVID-19 olfactory dysfunction. Cochrane Database Syst Rev 2021; 7:CD013877. [PMID: 34291812 PMCID: PMC8406518 DOI: 10.1002/14651858.cd013877.pub2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Loss of olfactory function is well recognised as a cardinal symptom of COVID-19 infection, and the ongoing pandemic has resulted in a large number of affected individuals with abnormalities in their sense of smell. For many, the condition is temporary and resolves within two to four weeks. However, in a significant minority the symptoms persist. At present, it is not known whether early intervention with any form of treatment (such as medication or olfactory training) can promote recovery and prevent persisting olfactory disturbance. OBJECTIVES: To assess the effects (benefits and harms) of interventions that have been used, or proposed, to prevent persisting olfactory dysfunction due to COVID-19 infection. A secondary objective is to keep the evidence up-to-date, using a living systematic review approach. SEARCH METHODS: The Cochrane ENT Information Specialist searched the Cochrane COVID-19 Study Register; Cochrane ENT Register; CENTRAL; Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished studies. The date of the search was 16 December 2020. SELECTION CRITERIA Randomised controlled trials including participants who had symptoms of olfactory disturbance following COVID-19 infection. Individuals who had symptoms for less than four weeks were included in this review. Studies compared any intervention with no treatment or placebo. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. Our primary outcomes were the presence of normal olfactory function, serious adverse effects and change in sense of smell. Secondary outcomes were the prevalence of parosmia, change in sense of taste, disease-related quality of life and other adverse effects (including nosebleeds/bloody discharge). We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: We included one study of 100 participants, which compared an intranasal steroid spray to no intervention. Participants in both groups were also advised to undertake olfactory training for the duration of the trial. Data were identified for only two of the prespecified outcomes for this review, and no data were available for the primary outcome of serious adverse effects. Intranasal corticosteroids compared to no intervention (all using olfactory training) Presence of normal olfactory function after three weeks of treatment was self-assessed by the participants, using a visual analogue scale (range 0 to 10, higher scores = better). A score of 10 represented "completely normal smell sensation". The evidence is very uncertain about the effect of intranasal corticosteroids on self-rated recovery of sense of smell (estimated absolute effect 619 per 1000 compared to 520 per 1000, risk ratio (RR) 1.19, 95% confidence interval (CI) 0.85 to 1.68; 1 study; 100 participants; very low-certainty evidence). Change in sense of smell was not reported, but the self-rated score for sense of smell was reported at the endpoint of the study with the same visual analogue scale (after three weeks of treatment). The median scores at endpoint were 10 (interquartile range (IQR) 9 to 10) for the group receiving intranasal corticosteroids, and 10 (IQR 5 to 10) for the group receiving no intervention (1 study; 100 participants; very low-certainty evidence). AUTHORS' CONCLUSIONS There is very limited evidence regarding the efficacy of different interventions at preventing persistent olfactory dysfunction following COVID-19 infection. However, we have identified a small number of additional ongoing studies in this area. As this is a living systematic review, the evidence will be updated regularly to incorporate new data from these, and other relevant studies, as they become available. For this (first) version of the living review, we identified a single study of intranasal corticosteroids to include in this review, which provided data for only two of our prespecified outcomes. The evidence was of very low certainty, therefore we were unable to determine whether intranasal corticosteroids may have a beneficial or harmful effect.
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Affiliation(s)
- Katie E Webster
- Cochrane ENT, Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Lisa O'Byrne
- Department of Otolaryngology Head and Neck Surgery, St Vincent's University Hospital, Dublin 4, Ireland
| | - Samuel MacKeith
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Carl Philpott
- Department of Medicine, Norwich Medical School, University of East Anglia, Norwich, UK
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24
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O'Byrne L, Webster KE, MacKeith S, Philpott C, Hopkins C, Burton MJ. Interventions for the treatment of persistent post-COVID-19 olfactory dysfunction. Cochrane Database Syst Rev 2021; 7:CD013876. [PMID: 34291813 PMCID: PMC8406942 DOI: 10.1002/14651858.cd013876.pub2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Olfactory dysfunction is an early and sensitive marker of COVID-19 infection. Although self-limiting in the majority of cases, when hyposmia or anosmia persists it can have a profound effect on quality of life. Little guidance exists on the treatment of post-COVID-19 olfactory dysfunction, however several strategies have been proposed from the evidence relating to the treatment of post-viral anosmia (such as medication or olfactory training). OBJECTIVES To assess the effects (benefits and harms) of interventions that have been used, or proposed, to treat persisting olfactory dysfunction due to COVID-19 infection. A secondary objective is to keep the evidence up-to-date, using a living systematic review approach. SEARCH METHODS: The Cochrane ENT Information Specialist searched the Cochrane COVID-19 Study Register; Cochrane ENT Register; CENTRAL; Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished studies. The date of the search was 16 December 2020. SELECTION CRITERIA Randomised controlled trials including participants who had symptoms of olfactory disturbance following COVID-19 infection. Only individuals who had symptoms for at least four weeks were included in this review. Studies compared any intervention with no treatment or placebo. DATA COLLECTION AND ANALYSIS We used standard Cochrane methodological procedures. Primary outcomes were the recovery of sense of smell, disease-related quality of life and serious adverse effects. Secondary outcomes were the change in sense of smell, general quality of life, prevalence of parosmia and other adverse effects (including nosebleeds/bloody discharge). We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS We included one study with 18 participants, which compared the use of a 15-day course of oral steroids combined with nasal irrigation (consisting of an intranasal steroid/mucolytic/decongestant solution) with no intervention. Psychophysical testing was used to assess olfactory function at baseline, 20 and 40 days. Systemic corticosteroids plus intranasal steroid/mucolytic/decongestant compared to no intervention Recovery of sense of smell was assessed after 40 days (25 days after cessation of treatment) using the Connecticut Chemosensory Clinical Research Center (CCCRC) score. This tool has a range of 0 to 100, and a score of ≥ 90 represents normal olfactory function. The evidence is very uncertain about the effect of this intervention on recovery of the sense of smell at one to three months (5/9 participants in the intervention group scored ≥ 90 compared to 0/9 in the control group; risk ratio (RR) 11.00, 95% confidence interval (CI) 0.70 to 173.66; 1 study; 18 participants; very low-certainty evidence). Change in sense of smell was assessed using the CCCRC score at 40 days. This study reported an improvement in sense of smell in the intervention group from baseline (median improvement in CCCRC score 60, interquartile range (IQR) 40) compared to the control group (median improvement in CCCRC score 30, IQR 25) (1 study; 18 participants; very low-certainty evidence). Serious adverse events andother adverse events were not identified in any participants of this study; however, it is unclear how these outcomes were assessed and recorded (1 study; 18 participants; very low-certainty evidence). AUTHORS' CONCLUSIONS There is very limited evidence available on the efficacy and harms of treatments for persistent olfactory dysfunction following COVID-19 infection. However, we have identified other ongoing trials in this area. As this is a living systematic review we will update the data regularly, as new results become available. For this (first) version of the living review we identified only one study with a small sample size, which assessed systemic steroids and nasal irrigation (intranasal steroid/mucolytic/decongestant). However, the evidence regarding the benefits and harms from this intervention to treat persistent post-COVID-19 olfactory dysfunction is very uncertain.
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Affiliation(s)
- Lisa O'Byrne
- Department of Otolaryngology Head and Neck Surgery, St Vincent's University Hospital, Dublin 4, Ireland
| | - Katie E Webster
- Cochrane ENT, Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Samuel MacKeith
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Carl Philpott
- Department of Medicine, Norwich Medical School, University of East Anglia, Norwich, UK
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25
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Lewis A, Frontera J, Placantonakis DG, Galetta S, Balcer L, Melmed KR. Cerebrospinal fluid from COVID-19 patients with olfactory/gustatory dysfunction: A review. Clin Neurol Neurosurg 2021; 207:106760. [PMID: 34146842 PMCID: PMC8196517 DOI: 10.1016/j.clineuro.2021.106760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 12/31/2022]
Abstract
Objective We reviewed the literature on cerebrospinal fluid (CSF) testing in patients with altered olfactory/gustatory function due to COVID-19 for evidence of viral neuroinvasion. Methods We performed a systematic review of Medline and Embase to identify publications that described at least one patient with COVID-19 who had altered olfactory/gustatory function and had CSF testing performed. The search ranged from December 1, 2019 to November 18, 2020. Results We identified 51 publications that described 70 patients who met inclusion criteria. Of 51 patients who had CSF SARS-CoV-2 PCR testing, 3 (6%) patients had positive results and 1 (2%) patient had indeterminate results. Cycle threshold (Ct; the number of amplification cycles required for the target gene to exceed the threshold, which is inversely related to viral load) was not provided for the patients with a positive PCR. The patient with indeterminate results had a Ct of 37 initially, then no evidence of SARS-CoV-2 RNA on repeat testing. Of 6 patients who had CSF SARS-CoV-2 antibody testing, 3 (50%) were positive. Testing to distinguish intrathecal antibody synthesis from transudation of antibodies to the CSF via breakdown of the blood-brain barrier was performed in 1/3 (33%) patients; this demonstrated antibody transmission to the CSF via transudation. Conclusion Detection of SARS-CoV-2 in CSF via PCR or evaluation for intrathecal antibody synthesis appears to be rare in patients with altered olfactory/gustatory function. While pathology studies are needed, our review suggests it is unlikely that these symptoms are related to viral neuroinvasion.
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Affiliation(s)
- Ariane Lewis
- Department of Neurology, NYU Langone Medical Center, New York, NY 10016, USA; Department of Neurosurgery, NYU Langone Medical Center, New York, NY 10016, USA.
| | - Jennifer Frontera
- Department of Neurology, NYU Langone Medical Center, New York, NY 10016, USA; Department of Neurosurgery, NYU Langone Medical Center, New York, NY 10016, USA
| | | | - Steven Galetta
- Department of Neurology, NYU Langone Medical Center, New York, NY 10016, USA; Department of Ophthalmology, NYU Langone Medical Center, New York, NY 10016, USA
| | - Laura Balcer
- Department of Neurology, NYU Langone Medical Center, New York, NY 10016, USA; Department of Ophthalmology, NYU Langone Medical Center, New York, NY 10016, USA; Department of Population Health, NYU Langone, Medical Center, New York, NY 10016, USA
| | - Kara R Melmed
- Department of Neurology, NYU Langone Medical Center, New York, NY 10016, USA; Department of Neurosurgery, NYU Langone Medical Center, New York, NY 10016, USA
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26
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de Melo GD, Lazarini F, Levallois S, Hautefort C, Michel V, Larrous F, Verillaud B, Aparicio C, Wagner S, Gheusi G, Kergoat L, Kornobis E, Donati F, Cokelaer T, Hervochon R, Madec Y, Roze E, Salmon D, Bourhy H, Lecuit M, Lledo PM. COVID-19-related anosmia is associated with viral persistence and inflammation in human olfactory epithelium and brain infection in hamsters. Sci Transl Med 2021; 13:eabf8396. [PMID: 33941622 PMCID: PMC8158965 DOI: 10.1126/scitranslmed.abf8396] [Citation(s) in RCA: 273] [Impact Index Per Article: 91.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/26/2021] [Accepted: 04/27/2021] [Indexed: 12/11/2022]
Abstract
Whereas recent investigations have revealed viral, inflammatory, and vascular factors involved in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lung pathogenesis, the pathophysiology of neurological disorders in coronavirus disease 2019 (COVID-19) remains poorly understood. Olfactory and taste dysfunction are common in COVID-19, especially in mildly symptomatic patients. Here, we conducted a virologic, molecular, and cellular study of the olfactory neuroepithelium of seven patients with COVID-19 presenting with acute loss of smell. We report evidence that the olfactory neuroepithelium is a major site of SARS-CoV2 infection with multiple cell types, including olfactory sensory neurons, support cells, and immune cells, becoming infected. SARS-CoV-2 replication in the olfactory neuroepithelium was associated with local inflammation. Furthermore, we showed that SARS-CoV-2 induced acute anosmia and ageusia in golden Syrian hamsters, lasting as long as the virus remained in the olfactory epithelium and the olfactory bulb. Last, olfactory mucosa sampling from patients showing long-term persistence of COVID-19-associated anosmia revealed the presence of virus transcripts and of SARS-CoV-2-infected cells, together with protracted inflammation. SARS-CoV-2 persistence and associated inflammation in the olfactory neuroepithelium may account for prolonged or relapsing symptoms of COVID-19, such as loss of smell, which should be considered for optimal medical management of this disease.
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Affiliation(s)
| | - Françoise Lazarini
- Perception and Memory Unit, Institut Pasteur, CNRS UMR3571, 75015 Paris, France
| | - Sylvain Levallois
- Biology of Infection Unit, Institut Pasteur, Paris, France; Inserm U1117, 75015 Paris, France
| | - Charlotte Hautefort
- Otolaryngology-head and Neck Surgery Department, Hopital Lariboisiere, Assistance Publique - Hôpitaux de Paris, Inserm U1141, Université de Paris, 75010 Paris, France
| | - Vincent Michel
- Perception and Memory Unit, Institut Pasteur, CNRS UMR3571, 75015 Paris, France
- Institut de l'Audition, Institut Pasteur, Paris, France; Inserm U1120, 75012 Paris, France
| | - Florence Larrous
- Lyssavirus Epidemiology and Neuropathology Unit, Institut Pasteur, 75015 Paris, France
| | - Benjamin Verillaud
- Otolaryngology-head and Neck Surgery Department, Hopital Lariboisiere, Assistance Publique - Hôpitaux de Paris, Inserm U1141, Université de Paris, 75010 Paris, France
| | - Caroline Aparicio
- Emergency Department, Hôpital Lariboisière, Assistance Publique - Hôpitaux de Paris, Université de Paris, 75010 Paris, France
| | - Sebastien Wagner
- Perception and Memory Unit, Institut Pasteur, CNRS UMR3571, 75015 Paris, France
| | - Gilles Gheusi
- Perception and Memory Unit, Institut Pasteur, CNRS UMR3571, 75015 Paris, France
- Laboratory of Experimental and Comparative Ethology, Université Sorbonne Paris Nord, Villetaneuse, France
| | - Lauriane Kergoat
- Lyssavirus Epidemiology and Neuropathology Unit, Institut Pasteur, 75015 Paris, France
| | - Etienne Kornobis
- Plateforme Technologique Biomics – Centre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, 75015 Paris, France
- Hub de Bioinformatique et Biostatistique – Département Biologie Computationnelle, Institut Pasteur, USR 3756 CNRS, 75015 Paris, France
| | - Flora Donati
- National Reference Center for Respiratory Viruses, Institut Pasteur, 75015 Paris, France
- Molecular Genetics of RNA Viruses, CNRS UMR3569, University of Paris, Institut Pasteur, 75015 Paris, France
| | - Thomas Cokelaer
- Plateforme Technologique Biomics – Centre de Ressources et Recherches Technologiques (C2RT), Institut Pasteur, 75015 Paris, France
- Hub de Bioinformatique et Biostatistique – Département Biologie Computationnelle, Institut Pasteur, USR 3756 CNRS, 75015 Paris, France
| | - Rémi Hervochon
- Otolaryngology-head and Neck Surgery Department, GHU Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Sorbonne Université, 75013 Paris, France
| | - Yoann Madec
- Emerging Diseases Epidemiology Unit, Institut Pasteur, 75015 Paris, France
| | - Emmanuel Roze
- Sorbonne Université, AP-HP, Hôpital de la Pitié-Salpêtrière, Département de Neurologie, Inserm U1127, CNRS UMR 7225, Institut du Cerveau, 75013 Paris, France
| | - Dominique Salmon
- Infectious Diseases and Immunology Department, Cochin Hotel Dieu Hospital, Assistance Publique - Hôpitaux de Paris, Université de Paris, 75015 Paris, France
| | - Hervé Bourhy
- Lyssavirus Epidemiology and Neuropathology Unit, Institut Pasteur, 75015 Paris, France
| | - Marc Lecuit
- Biology of Infection Unit, Institut Pasteur, Paris, France; Inserm U1117, 75015 Paris, France
- Université de Paris, Necker-Enfants Malades University Hospital, Division of Infectious Diseases and Tropical Medicine, Institut Imagine, AP-HP, 75015 Paris, France
| | - Pierre-Marie Lledo
- Perception and Memory Unit, Institut Pasteur, CNRS UMR3571, 75015 Paris, France
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27
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Dörig P, Gunder N, Witt M, Welge-Lüssen A, Hummel T. [Future therapeutic strategies for olfactory disorders: electrical stimulation, stem cell therapy, and transplantation of olfactory epithelium-an overview]. HNO 2021; 69:623-632. [PMID: 33988723 PMCID: PMC8120256 DOI: 10.1007/s00106-021-01060-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2021] [Indexed: 11/08/2022]
Abstract
Passagere oder permanente Riechstörungen können verschiedene Ursachen haben. Ganz aktuell berichtet eine Vielzahl von Patienten im Rahmen von COVID-19-Infektionen über ein fehlendes oder vermindertes Riechvermögen. In der Vergangenheit wurden vielfältige Therapieoptionen untersucht, diese variieren vom Riechtraining über Akupunktur und medikamentöse Therapien bis hin zur transkraniellen Magnetstimulation oder, z. B. bei ausgeprägten qualitativen Riechstörungen, der chirurgischen Resektion der Riechschleimhaut. Die Entwicklung einer bioelektrischen Nase, z. B. in Verbindung mit direkter elektrischer Stimulation des Bulbus olfactorius, oder die Transplantation von Riechschleimhaut oder von Stammzellen stellen Behandlungsmöglichkeiten der Zukunft dar. Die Grundlagen für diese Entwicklungen sowie der Stand des Wissens werden in der vorliegenden Arbeit erläutert.
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Affiliation(s)
- P Dörig
- Universitäts-HNO Klinik Basel, Petersgraben 4, 4031, Basel, Schweiz.
| | - N Gunder
- Universitäts-HNO Klinik Dresden, Dresden, Deutschland
| | - M Witt
- Institut für Anatomie, Universitätsmedizin Rostock, Rostock, Deutschland
| | - A Welge-Lüssen
- Universitäts-HNO Klinik Basel, Petersgraben 4, 4031, Basel, Schweiz
| | - T Hummel
- Universitäts-HNO Klinik Dresden, Dresden, Deutschland
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28
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Beckers E, Chouvel P, Cassetto V, Mustin V. Sudden sensorineural hearing loss in COVID-19: A case report and literature review. Clin Case Rep 2021; 9:2300-2304. [PMID: 33936683 PMCID: PMC8077296 DOI: 10.1002/ccr3.4019] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/02/2021] [Accepted: 02/21/2021] [Indexed: 12/23/2022] Open
Abstract
We encourage SARS-CoV-2 polymerase chain reaction in the diagnostic workup of patients currently presenting with sudden sensorineural hearing loss.
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Affiliation(s)
- Eline Beckers
- Department of Otorhinolaryngology‐Head and Neck SurgeryCliniques de l’EuropeBrusselsBelgium
| | - Pascale Chouvel
- Department of Otorhinolaryngology‐Head and Neck SurgeryCliniques de l’EuropeBrusselsBelgium
| | | | - Vincent Mustin
- Department of Otorhinolaryngology‐Head and Neck SurgeryCliniques de l’EuropeBrusselsBelgium
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29
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Vandersteen C, Payne M, Dumas LE, Metelkina-Fernandez V, Plonka A, Chirio D, Demonchy E, Risso K, Askenazy-Gittard F, Guevara N, Castillo L, Manera V, Gros A. Persistent olfactory complaints after COVID-19: a new interpretation of the psychophysical olfactory scores. RHINOLOGY ONLINE 2021. [DOI: 10.4193/rhinol/21.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background: Sudden olfactory loss is a major symptom of SARS-CoV-2 infection and has a negative impact on daily life quality. Almost 80% of disorders regress spontaneously. No precise characterization of the medium- and long-term olfactory symptoms has been carried out yet, apart from self-assessments. The main objective of this work was to characterize persistent smell disorders in this population. Methodology: Consecutive patients consulting to the ENT department with post-Covid19 olfactory loss were included. The clinical examination included an analog scale for the self-assessment of olfactory recovery), a nasofibroscopy, the Sniffin’ Stick Test and the short version of the Questionnaire of olfactory disorders. Results: Among the 34 patients included, based on the Sniffin’ Sticks Test, 29.4% (n=10) could be classified as normosmic, 55.9% (n=19) as hyposmic and 14.7% (n=5) as functional anosmic). Only olfactory identification impairment was significantly correlated with olfactory complaint and daily anxiety and annoyance related to lack of olfaction recovery. This identification disorder seemed to worsen over time. Conclusions: It is crucial to assess odor identification disorders in case of persistent olfactory complaints after COVID-19. It is fundamental to target this disorder, as it does not improve spontaneously and negatively impact quality of life.
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Duyan M, Ozturan IU, Altas M. Delayed Parosmia Following SARS-CoV-2 Infection: a Rare Late Complication of COVID-19. ACTA ACUST UNITED AC 2021; 3:1200-1202. [PMID: 33817555 PMCID: PMC7998087 DOI: 10.1007/s42399-021-00876-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2021] [Indexed: 12/11/2022]
Abstract
In this report, we present two cases of delayed parosmia, a rare complication that occurs in the late period after COVID-19. A 28-year-old male and a 32-year-old female, found to be positive in rRT-PCR tests for SARS-CoV-2, had a loss of taste and smell, respectively. Following the regaining of their ability to smell after 87 and 72 days, respectively, the male patient reported that the smell he perceived felt the smell of burnt rubber, while the female patient stated that it was similar to the smell of onion. As a result of evaluations, a diagnosis of delayed parosmia was made occurring in the late period secondary to SARS-CoV-2 infection. Although anosmia is a common symptom in the early phase of COVID-19, olfactory damage due to Sars-CoV-2 can be persistent, and distorted sense of smell can be prolonged.
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Affiliation(s)
- Murat Duyan
- Department of Emergency Medicine, Antalya Training and Research Hospital, Antalya, Turkey
| | | | - Murat Altas
- Department of Neurosurgery, Akdeniz University Faculty of Medicine, Antalya, Turkey
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Brain Metabolic Correlates of Persistent Olfactory Dysfunction after SARS-Cov2 Infection. Biomedicines 2021; 9:biomedicines9030287. [PMID: 33808956 PMCID: PMC7998481 DOI: 10.3390/biomedicines9030287] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/04/2021] [Accepted: 03/09/2021] [Indexed: 12/20/2022] Open
Abstract
We aimed to evaluate the brain hypometabolic signature of persistent isolated olfactory dysfunction after SARS-CoV-2 infection. Twenty-two patients underwent whole-body [18F]-FDG PET, including a dedicated brain acquisition at our institution between May and December 2020 following their recovery after SARS-Cov2 infection. Fourteen of these patients presented isolated persistent hyposmia (smell diskettes olfaction test was used). A voxel-wise analysis (using Statistical Parametric Mapping software version 8 (SPM8)) was performed to identify brain regions of relative hypometabolism in patients with hyposmia with respect to controls. Structural connectivity of these regions was assessed (BCB toolkit). Relative hypometabolism was demonstrated in bilateral parahippocampal and fusiform gyri and in left insula in patients with respect to controls. Structural connectivity maps highlighted the involvement of bilateral longitudinal fasciculi. This study provides evidence of cortical hypometabolism in patients with isolated persistent hyposmia after SARS-Cov2 infection. [18F]-FDG PET may play a role in the identification of long-term brain functional sequelae of COVID-19.
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Hopkins C, Lechien JR, Saussez S. 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. Med Hypotheses 2021; 146:110406. [PMID: 33246692 PMCID: PMC7678428 DOI: 10.1016/j.mehy.2020.110406] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 11/17/2020] [Indexed: 12/21/2022]
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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Affiliation(s)
- Claire Hopkins
- Guy's and St Thomas NHS Foundation Trust, London, UK; King's College, London, UK.
| | - Jerome R Lechien
- COVID-19 Task Force of the Young-Otolaryngologists of the International Federations of Oto-rhino-laryngological Societies (YO-IFOS), Paris, France; Department of Human Anatomy and Experimental Oncology, Faculty of Medicine, UMONS Research Institute for Health Sciences and Technology, University of Mons (UMons), Mons, Belgium; Department of Otorhinolaryngology and Head and Neck Surgery, CHU Saint-Pierre, School of Medicine, CHU de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium; Department of Otolaryngology-Head and Neck Surgery, School of Medicine, UFR Simone Veil, Foch Hospital, Université Versailles Saint-Quentin-en-Yvelines (Paris Saclay University), Paris, France
| | - Sven Saussez
- COVID-19 Task Force of the Young-Otolaryngologists of the International Federations of Oto-rhino-laryngological Societies (YO-IFOS), Paris, France; Department of Human Anatomy and Experimental Oncology, Faculty of Medicine, UMONS Research Institute for Health Sciences and Technology, University of Mons (UMons), Mons, Belgium; Department of Otorhinolaryngology and Head and Neck Surgery, CHU Saint-Pierre, School of Medicine, CHU de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
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