COVID-19-associated anosmia: Difference between revisions

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The extent of potential [[olfactory]] [[dysfunction]] due to [[COVID-19]] is still unclear.<ref name="pmid32563019" />
The extent of potential [[olfactory]] [[dysfunction]] due to [[COVID-19]] is still unclear.<ref name="pmid32563019" />
To view the complete page of COVID-19, [[COVID-19|click here]].


==Historical Perspective==
==Historical Perspective==
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*In April 17, Shweta et al. used [[Artificial intelligence systems integration|artificial intelligence]] with the most advanced deep neural networks technology at the time, and proved that there was a 28.6-fold probability of having [[anosmia]] in [[COVID-19]]-positive than those negative, and that [[anosmia]]/[[dysgeusia]] was one of the earliest signatures of [[COVID-19]].<ref name="url[2004.09338] Augmented Curation of Unstructured Clinical Notes from a Massive EHR System Reveals Specific Phenotypic Signature of Impending COVID-19 Diagnosis">{{cite web |url=https://arxiv.org/abs/2004.09338 |title=[2004.09338] Augmented Curation of Unstructured Clinical Notes from a Massive EHR System Reveals Specific Phenotypic Signature of Impending COVID-19 Diagnosis |format= |work= |accessdate=}}</ref><ref name="pmid32563019" />
*In April 17, Shweta et al. used [[Artificial intelligence systems integration|artificial intelligence]] with the most advanced deep neural networks technology at the time, and proved that there was a 28.6-fold probability of having [[anosmia]] in [[COVID-19]]-positive than those negative, and that [[anosmia]]/[[dysgeusia]] was one of the earliest signatures of [[COVID-19]].<ref name="url[2004.09338] Augmented Curation of Unstructured Clinical Notes from a Massive EHR System Reveals Specific Phenotypic Signature of Impending COVID-19 Diagnosis">{{cite web |url=https://arxiv.org/abs/2004.09338 |title=[2004.09338] Augmented Curation of Unstructured Clinical Notes from a Massive EHR System Reveals Specific Phenotypic Signature of Impending COVID-19 Diagnosis |format= |work= |accessdate=}}</ref><ref name="pmid32563019" />
*In April 22, 2020 a study made by Beltrán-Corbellini et al. proved that the [[incidence]] rate of [[anosmia]] was significantly higher in individuals with [[COVID-19]] (39.2%) patients than those with [[influenza]] (12.5%).<ref name="Beltrán‐CorbelliniChico‐García20202">{{cite journal|last1=Beltrán‐Corbellini|first1=Á.|last2=Chico‐García|first2=J. L.|last3=Martínez‐Poles|first3=J.|last4=Rodríguez‐Jorge|first4=F.|last5=Natera‐Villalba|first5=E.|last6=Gómez‐Corral|first6=J.|last7=Gómez‐López|first7=A.|last8=Monreal|first8=E.|last9=Parra‐Díaz|first9=P.|last10=Cortés‐Cuevas|first10=J. L.|last11=Galán|first11=J. C.|last12=Fragola‐Arnau|first12=C.|last13=Porta‐Etessam|first13=J.|last14=Masjuan|first14=J.|last15=Alonso‐Cánovas|first15=A.|title=Acute‐onset smell and taste disorders in the context of COVID‐19: a pilot multicentre polymerase chain reaction based case–control study|journal=European Journal of Neurology|year=2020|issn=1351-5101|doi=10.1111/ene.14273}}</ref>
*In April 22, 2020 a study made by Beltrán-Corbellini et al. proved that the [[incidence]] rate of [[anosmia]] was significantly higher in individuals with [[COVID-19]] (39.2%) patients than those with [[influenza]] (12.5%).<ref name="Beltrán‐CorbelliniChico‐García20202">{{cite journal|last1=Beltrán‐Corbellini|first1=Á.|last2=Chico‐García|first2=J. L.|last3=Martínez‐Poles|first3=J.|last4=Rodríguez‐Jorge|first4=F.|last5=Natera‐Villalba|first5=E.|last6=Gómez‐Corral|first6=J.|last7=Gómez‐López|first7=A.|last8=Monreal|first8=E.|last9=Parra‐Díaz|first9=P.|last10=Cortés‐Cuevas|first10=J. L.|last11=Galán|first11=J. C.|last12=Fragola‐Arnau|first12=C.|last13=Porta‐Etessam|first13=J.|last14=Masjuan|first14=J.|last15=Alonso‐Cánovas|first15=A.|title=Acute‐onset smell and taste disorders in the context of COVID‐19: a pilot multicentre polymerase chain reaction based case–control study|journal=European Journal of Neurology|year=2020|issn=1351-5101|doi=10.1111/ene.14273}}</ref>
*To view the historical perspective of COVID-19, [[COVID-19 historical perspective|click here]].


==Classification==
==Classification==


* In general, olfactory dysfunction can be classified as:
* In general, [[Olfaction|olfactory]] dysfunction can be classified as:
**Anosmia. Total incapacity for odor detection.<ref name="pmid32466862" />
**[[Anosmia]]. Total incapacity for [[odor]] perception.<ref name="pmid32466862" />
**Hyposmia.Increased odor detection threshold. This is the most common type of olfactory dysfunction in patients with COVID-19.<ref name="pmid32466862" />
**[[Hyposmia]].Increased [[odor]] detection [[Threshold Limit Value|threshold]]. This is the most common type of olfactory dysfunction in patients with [[COVID-19]].<ref name="pmid32466862" />
**Hyperosmia.Decreased odor detection threshold.<ref name="pmid32466862" />
**[[Hyperosmia]].Decreased odor detection threshold.<ref name="pmid32466862" />
**Dysosmia. It is a qualitative alteration of smell, where there is an incorrect identification of odors. At the same time, dysosmias can be classified as parosmias (altered perception of an odor when stimulus is present) and phantosmias (perception of an odor without real stimulation).<ref name="pmid32466862" />
**[[Dysosmia]]. It is a [[qualitative]] alteration of [[smell]], where there is an incorrect identification of [[Odor|odors]]. At the same time, [[Dysosmia|dysosmias]] can be classified as [[Parosmia|parosmias]] (altered [[perception]] of an [[odor]] when stimulus is present) and [[Phantosmia|phantosmias]] (perception of an [[odor]] without real [[stimulation]]).<ref name="pmid32466862" />
*There is no established system for the classification of [[COVID-19]] associated [[anosmia]].
*There is no established system for the classification of [[COVID-19]] associated [[anosmia]].
*To view the classification of COVID-19, [[COVID-19 classification|click here]].


==Pathophysiology==
==Pathophysiology==
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*Due to the special anatomy of the [[olfactory system]], [[COVID-19]] [[Virus (biology)|vi]][[Virus (biology)|rus]] may invade the [[Central nervous system infection|central nervous system infections]] via the [[cribriform plate]].<ref name="pmid32563019" /><ref name="pmid23601101">{{cite journal |vauthors=Koyuncu OO, Hogue IB, Enquist LW |title=Virus infections in the nervous system |journal=Cell Host Microbe |volume=13 |issue=4 |pages=379–93 |date=April 2013 |pmid=23601101 |pmc=3647473 |doi=10.1016/j.chom.2013.03.010 |url=}}</ref>
*Due to the special anatomy of the [[olfactory system]], [[COVID-19]] [[Virus (biology)|vi]][[Virus (biology)|rus]] may invade the [[Central nervous system infection|central nervous system infections]] via the [[cribriform plate]].<ref name="pmid32563019" /><ref name="pmid23601101">{{cite journal |vauthors=Koyuncu OO, Hogue IB, Enquist LW |title=Virus infections in the nervous system |journal=Cell Host Microbe |volume=13 |issue=4 |pages=379–93 |date=April 2013 |pmid=23601101 |pmc=3647473 |doi=10.1016/j.chom.2013.03.010 |url=}}</ref>
*It is thought that [[Goblet cell|Goblet cells]] and [[ciliated cells]] of the [[nasal mucosa]] may be the initial site of [[COVID-19]] infection when [[transmission]] is through airway.<ref name="pmid32563019" /><ref name="pmid32327758">{{cite journal |vauthors=Sungnak W, Huang N, Bécavin C, Berg M, Queen R, Litvinukova M, Talavera-López C, Maatz H, Reichart D, Sampaziotis F, Worlock KB, Yoshida M, Barnes JL |title=SARS-CoV-2 entry factors are highly expressed in nasal epithelial cells together with innate immune genes |journal=Nat. Med. |volume=26 |issue=5 |pages=681–687 |date=May 2020 |pmid=32327758 |doi=10.1038/s41591-020-0868-6 |url=}}</ref>
*It is thought that [[Goblet cell|Goblet cells]] and [[ciliated cells]] of the [[nasal mucosa]] may be the initial site of [[COVID-19]] infection when [[transmission]] is through airway.<ref name="pmid32563019" /><ref name="pmid32327758">{{cite journal |vauthors=Sungnak W, Huang N, Bécavin C, Berg M, Queen R, Litvinukova M, Talavera-López C, Maatz H, Reichart D, Sampaziotis F, Worlock KB, Yoshida M, Barnes JL |title=SARS-CoV-2 entry factors are highly expressed in nasal epithelial cells together with innate immune genes |journal=Nat. Med. |volume=26 |issue=5 |pages=681–687 |date=May 2020 |pmid=32327758 |doi=10.1038/s41591-020-0868-6 |url=}}</ref>
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>Studies suggest that [[viruses]] may propagate from the [[Nasal cavity|nasal cavit]]<nowiki/>y to the [[olfactory bulb]] through neuron-to-neuron [[axonal]] transport or passive diffusion of released viral particles.<ref name="pmid29925652" />
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>Studies suggest that [[viruses]] may propagate from the [[Nasal cavity|nasal cavit]]<nowiki/>y to the [[olfactory bulb]] through neuron-to-neuron [[axonal]] transport, passive diffusion of released viral particles, or hematogenously.<ref name="pmid29925652" /><ref name="CapelliGatti2020">{{cite journal|last1=Capelli|first1=Marco|last2=Gatti|first2=Patrizia|title=Anosmia and COVID-19 in south Lombardy: description of the first cases series in Europe|journal=B-ENT|volume=16|issue=1|year=2020|pages=86–90|issn=26844907|doi=10.5152/B-ENT.2020.20129}}</ref>
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>Several theories have been given to explain the variation of [[Incidence|in]]<nowiki/>[[Incidence|cidence]] of [[Olfaction|olfactory]] [[dysfunction]] among different countries, among these reasons are the [[pathogenicity]] and [[mutation]] capability of [[COVID-19]].<ref name="YaoLu2020">{{cite journal|last1=Yao|first1=Hangping|last2=Lu|first2=Xiangyun|last3=Chen|first3=Qiong|last4=Xu|first4=Kaijin|last5=Chen|first5=Yu|last6=Cheng|first6=Linfang|last7=Liu|first7=Fumin|last8=Wu|first8=Zhigang|last9=Wu|first9=Haibo|last10=Jin|first10=Changzhong|last11=Zheng|first11=Min|last12=Wu|first12=Nanping|last13=Jiang|first13=Chao|last14=Li|first14=Lanjuan|year=2020|doi=10.1101/2020.04.14.20060160}}</ref><ref name="pmid32563019" /><ref name="urlwww.thelancet.com">{{cite web |url=https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30079-5/Abstract |title=www.thelancet.com |format= |work= |accessdate=}}</ref>
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>Several theories have been given to explain the variation of [[Incidence|in]]<nowiki/>[[Incidence|cidence]] of [[Olfaction|olfactory]] [[dysfunction]] among different countries, among these reasons are the [[pathogenicity]] and [[mutation]] capability of [[COVID-19]].<ref name="YaoLu2020">{{cite journal|last1=Yao|first1=Hangping|last2=Lu|first2=Xiangyun|last3=Chen|first3=Qiong|last4=Xu|first4=Kaijin|last5=Chen|first5=Yu|last6=Cheng|first6=Linfang|last7=Liu|first7=Fumin|last8=Wu|first8=Zhigang|last9=Wu|first9=Haibo|last10=Jin|first10=Changzhong|last11=Zheng|first11=Min|last12=Wu|first12=Nanping|last13=Jiang|first13=Chao|last14=Li|first14=Lanjuan|year=2020|doi=10.1101/2020.04.14.20060160}}</ref><ref name="pmid32563019" /><ref name="urlwww.thelancet.com">{{cite web |url=https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30079-5/Abstract |title=www.thelancet.com |format= |work= |accessdate=}}</ref>
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>It is thought that the [[Genotype|genotypes]] of A and C [[Strain (biology)|strains]] of [[COVID-19|SARS-Cov]]<nowiki/>[[COVID-19|-2]] have a greater [[pathogenicity]] for the nasal cavity in humans, this explains the higher [[incidence]] of [[anosmia]] in European countries, where these [[Strain (biology)|strains]] prevail.<ref name="pmid32563019" /><ref name="ForsterForster2020">{{cite journal|last1=Forster|first1=Peter|last2=Forster|first2=Lucy|last3=Renfrew|first3=Colin|last4=Forster|first4=Michael|title=Phylogenetic network analysis of SARS-CoV-2 genomes|journal=Proceedings of the National Academy of Sciences|volume=117|issue=17|year=2020|pages=9241–9243|issn=0027-8424|doi=10.1073/pnas.2004999117}}</ref>
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>It is thought that the [[Genotype|genotypes]] of A and C [[Strain (biology)|strains]] of [[COVID-19|SARS-Cov]]<nowiki/>[[COVID-19|-2]] have a greater [[pathogenicity]] for the nasal cavity in humans, this explains the higher [[incidence]] of [[anosmia]] in European countries, where these [[Strain (biology)|strains]] prevail.<ref name="pmid32563019" /><ref name="ForsterForster2020">{{cite journal|last1=Forster|first1=Peter|last2=Forster|first2=Lucy|last3=Renfrew|first3=Colin|last4=Forster|first4=Michael|title=Phylogenetic network analysis of SARS-CoV-2 genomes|journal=Proceedings of the National Academy of Sciences|volume=117|issue=17|year=2020|pages=9241–9243|issn=0027-8424|doi=10.1073/pnas.2004999117}}</ref>
*<nowiki/><nowiki/><nowiki/><nowiki/><nowiki/>To view the pathophysiology of COVID-19, click here.


==Causes==
==Causes==
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* Now in day, more than 200 types of [[viruses]] are identified to cause [[anosmia]]; [[coronavirus]] [[Strain (biology)|strains]] (7 of them) are responsable of 10-15% of the cases.<ref name="pmid32277751" /><ref name="pmid16253889">{{cite journal |vauthors=Eccles R |title=Understanding the symptoms of the common cold and influenza |journal=Lancet Infect Dis |volume=5 |issue=11 |pages=718–25 |date=November 2005 |pmid=16253889 |pmc=7185637 |doi=10.1016/S1473-3099(05)70270-X |url=}}</ref><ref name="pmid32563019" />
* Now in day, more than 200 types of [[viruses]] are identified to cause [[anosmia]]; [[coronavirus]] [[Strain (biology)|strains]] (7 of them) are responsable of 10-15% of the cases.<ref name="pmid32277751" /><ref name="pmid16253889">{{cite journal |vauthors=Eccles R |title=Understanding the symptoms of the common cold and influenza |journal=Lancet Infect Dis |volume=5 |issue=11 |pages=718–25 |date=November 2005 |pmid=16253889 |pmc=7185637 |doi=10.1016/S1473-3099(05)70270-X |url=}}</ref><ref name="pmid32563019" />
*To view causes of COVID-19, click here.


==Differentiating COVID-19-associated anosmia from other Diseases==
==Differentiating COVID-19-associated anosmia from other Diseases==


* [[Anosmia]] due to [[COVID-19]] [[infection]] may present indenticaly as other [[Anosmia|anosmias]] from [[Upper respiratory infections|upper respiratory viral infections]].<br />
* When differentiating [[anosmia]] due to [[COVID-19]] [[infection]] from other causes, it is important to pay attention into the presentation:
**Acute smell loss (other [[Upper respiratory infections|upper respiratory viral infections]], head injuries).<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
**Chronic smell loss (normal aging, rhinitis, nasal polyps, neoplasms, neurodegenerative disorders).<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
**Intermittent smell loss (allergic rhinitis, use of topical drugs).<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
**Congenital smell loss (Kallmann syndrome).<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
*To view the differential diagnosis of COVID-19, click here.<br />


==Epidemiology and Demographics==
==Epidemiology and Demographics==
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|75.8%
|75.8%
|}
|}
<br />
 
* To view screening for COVID-19, click here.<br />


==Risk Factors==
==Risk Factors==
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**Genetic susceptibility
**Genetic susceptibility
*Susceptibility to [[COVID-19]] [[infection]] is influenced to some degree by the host genotype, making a 47-fold heritability for anosmia.<ref name="pmid32563019" /><ref name="WilliamsFreydin2020">{{cite journal|last1=Williams|first1=Frances MK|last2=Freydin|first2=Maxim|last3=Mangino|first3=Massimo|last4=Couvreur|first4=Simon|last5=Visconti|first5=Alessia|last6=Bowyer|first6=Ruth CE|last7=Le Roy|first7=Caroline I|last8=Falchi|first8=Mario|last9=Sudre|first9=Carole|last10=Davies|first10=Richard|last11=Hammond|first11=Christopher|last12=Menni|first12=Cristina|last13=Steves|first13=Claire|last14=Spector|first14=Tim|year=2020|doi=10.1101/2020.04.22.20072124}}</ref>
*Susceptibility to [[COVID-19]] [[infection]] is influenced to some degree by the host genotype, making a 47-fold heritability for anosmia.<ref name="pmid32563019" /><ref name="WilliamsFreydin2020">{{cite journal|last1=Williams|first1=Frances MK|last2=Freydin|first2=Maxim|last3=Mangino|first3=Massimo|last4=Couvreur|first4=Simon|last5=Visconti|first5=Alessia|last6=Bowyer|first6=Ruth CE|last7=Le Roy|first7=Caroline I|last8=Falchi|first8=Mario|last9=Sudre|first9=Carole|last10=Davies|first10=Richard|last11=Hammond|first11=Christopher|last12=Menni|first12=Cristina|last13=Steves|first13=Claire|last14=Spector|first14=Tim|year=2020|doi=10.1101/2020.04.22.20072124}}</ref>
*To view the epidemiology and demographics of COVID-19, click here.


==Screening==
==Screening==


* Several [[ENT]] societies in the United Kingdom and the United States, have advised to treat [[anosmia]] marker of [[SARS-CoV-2]] [[infection]].<ref name=":0">{{Cite journal|last=Robert Pellegrin, Keiland W. Cooper, Antonella Di Pizio, Paule V. Joseph, Surabhi Bhutani, Valentina Parma|first=|date=2020|title=Corona Viruses and the Chemical Senses:
*A screening strategy, duly validated for olfactory disfunction in COVID-19, consists of carrying out specific questionnaires, such as the ''Questionnaire for Olfactory Disfunction''.<ref name="pmid32466862" /><ref name="pmid26384780">{{cite journal |vauthors=Nguyen DT, Rumeau C, Gallet P, Jankowski R |title=Olfactory exploration: State of the art |journal=Eur Ann Otorhinolaryngol Head Neck Dis |volume=133 |issue=2 |pages=113–8 |date=April 2016 |pmid=26384780 |doi=10.1016/j.anorl.2015.08.038 |url=}}</ref><ref name="pmid22566102">{{cite journal |vauthors=Simopoulos E, Katotomichelakis M, Gouveris H, Tripsianis G, Livaditis M, Danielides V |title=Olfaction-associated quality of life in chronic rhinosinusitis: adaptation and validation of an olfaction-specific questionnaire |journal=Laryngoscope |volume=122 |issue=7 |pages=1450–4 |date=July 2012 |pmid=22566102 |doi=10.1002/lary.23349 |url=}}</ref>
*Several [[ENT]] societies in the United Kingdom and the United States, have advised to treat [[anosmia]] marker of [[SARS-CoV-2]] [[infection]].<ref name=":0">{{Cite journal|last=Robert Pellegrin, Keiland W. Cooper, Antonella Di Pizio, Paule V. Joseph, Surabhi Bhutani, Valentina Parma|first=|date=2020|title=Corona Viruses and the Chemical Senses:
Past, Present, and Future|url=|journal=Oxford University|volume=|pages=|via=}}</ref><ref name="urlwww.entuk.org">{{cite web |url=https://www.entuk.org/sites/default/files/files/Loss%20of%20sense%20of%20smell%20as%20marker%20of%20COVID.pdf |title=www.entuk.org |format= |work= |accessdate=}}</ref><ref name="urlAAO-HNSF 2020 Annual Meeting & OTO Experience | American Academy of Otolaryngology-Head and Neck Surgery">{{cite web |url=https://www.entnet.org/content/aao-hnsf-2020-annual-meeting-oto-experience |title=AAO-HNSF 2020 Annual Meeting & OTO Experience &#124; American Academy of Otolaryngology-Head and Neck Surgery |format= |work= |accessdate=}}</ref>
Past, Present, and Future|url=|journal=Oxford University|volume=|pages=|via=}}</ref><ref name="urlwww.entuk.org">{{cite web |url=https://www.entuk.org/sites/default/files/files/Loss%20of%20sense%20of%20smell%20as%20marker%20of%20COVID.pdf |title=www.entuk.org |format= |work= |accessdate=}}</ref><ref name="urlAAO-HNSF 2020 Annual Meeting & OTO Experience | American Academy of Otolaryngology-Head and Neck Surgery">{{cite web |url=https://www.entnet.org/content/aao-hnsf-2020-annual-meeting-oto-experience |title=AAO-HNSF 2020 Annual Meeting & OTO Experience &#124; American Academy of Otolaryngology-Head and Neck Surgery |format= |work= |accessdate=}}</ref>
* The [[American Academy of Otolaryngology]] (AAO) proposed for [[anosmia]], [[hyposmia]], and [[dysgeusia]] to be added to the list of screening tools for [[COVID-19]] in otherwise [[asymptomatic]] individuals.<ref name="urlAAO-HNSF 2020 Annual Meeting & OTO Experience | American Academy of Otolaryngology-Head and Neck Surgery" /><ref name=":0" />
* The [[American Academy of Otolaryngology]] (AAO) proposed for [[anosmia]], [[hyposmia]], and [[dysgeusia]] to be added to the list of screening tools for [[COVID-19]] in otherwise [[asymptomatic]] individuals.<ref name="urlAAO-HNSF 2020 Annual Meeting & OTO Experience | American Academy of Otolaryngology-Head and Neck Surgery" /><ref name=":0" />
*A screening strategy, duly validated for olfactory disfunction in COVID-19, consists of carrying out specific questionnaires, such as the ''Questionnaire for Olfactory Disfunction''.<ref name="pmid32466862" /><ref name="pmid26384780">{{cite journal |vauthors=Nguyen DT, Rumeau C, Gallet P, Jankowski R |title=Olfactory exploration: State of the art |journal=Eur Ann Otorhinolaryngol Head Neck Dis |volume=133 |issue=2 |pages=113–8 |date=April 2016 |pmid=26384780 |doi=10.1016/j.anorl.2015.08.038 |url=}}</ref><ref name="pmid22566102">{{cite journal |vauthors=Simopoulos E, Katotomichelakis M, Gouveris H, Tripsianis G, Livaditis M, Danielides V |title=Olfaction-associated quality of life in chronic rhinosinusitis: adaptation and validation of an olfaction-specific questionnaire |journal=Laryngoscope |volume=122 |issue=7 |pages=1450–4 |date=July 2012 |pmid=22566102 |doi=10.1002/lary.23349 |url=}}</ref>
*In the absence of available solid data, the recommendation should be to perform nasal swabs on any patient with recent onset anosmia, duly assessed.<ref name="pmid32466862" />
 
*To view screening for COVID-19, click here.<br />
<br />


==Natural History, Complications, and Prognosis==
==Natural History, Complications, and Prognosis==
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* Approximately 82% of patients with [[anosmia]] related to [[COVID-19]] recover within 2 weeks and 98% of them within 28 days.<ref name="pmid32563019" /><ref name="pmid323055632" /><ref name="pmid32279441">{{cite journal |vauthors=Yan CH, Faraji F, Prajapati DP, Boone CE, DeConde AS |title=Association of chemosensory dysfunction and COVID-19 in patients presenting with influenza-like symptoms |journal=Int Forum Allergy Rhinol |volume= |issue= |pages= |date=April 2020 |pmid=32279441 |pmc=7262089 |doi=10.1002/alr.22579 |url=}}</ref>
* Approximately 82% of patients with [[anosmia]] related to [[COVID-19]] recover within 2 weeks and 98% of them within 28 days.<ref name="pmid32563019" /><ref name="pmid323055632" /><ref name="pmid32279441">{{cite journal |vauthors=Yan CH, Faraji F, Prajapati DP, Boone CE, DeConde AS |title=Association of chemosensory dysfunction and COVID-19 in patients presenting with influenza-like symptoms |journal=Int Forum Allergy Rhinol |volume= |issue= |pages= |date=April 2020 |pmid=32279441 |pmc=7262089 |doi=10.1002/alr.22579 |url=}}</ref>
*The intensity and duration of the olfactory disfunction associated to COVID-19, is highly variable depending on the capacity and rate of regeneration of the neuroeptielium.<ref name="pmid32466862" />
*The intensity and duration of the olfactory disfunction associated to COVID-19, is highly variable depending on the capacity and rate of regeneration of the neuroeptielium.<ref name="pmid32466862" />
*To view natural history, complications, and prognosis of COVID-19, click here.


==Diagnosis==
==Diagnosis==
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* In many studies, full [[Olfaction|olfactory]] [[Function (biology)|function]] tests have been disregarded.<ref name="pmid32563019" />
* In many studies, full [[Olfaction|olfactory]] [[Function (biology)|function]] tests have been disregarded.<ref name="pmid32563019" />
*[[Olfaction|Olfactory]] [[Function (biology)|function]] [[test|tests]] is mainly carried out semi-quantitatively using olfactory bars or bottles kits, which are presented to the patient in order to determine the olfaction thresholds.<ref name="pmid32466862">{{cite journal |vauthors=Lop Gros J, Iglesias Coma M, González Farré M, Serra Pujadas C |title=Olfactory dysfunction in COVID-19, a review of the evidence and implications for pandemic management |journal=Acta Otorrinolaringol Esp |volume= |issue= |pages= |date=May 2020 |pmid=32466862 |doi=10.1016/j.otorri.2020.04.003 |url=}}</ref>
*[[Olfaction|Olfactory]] [[Function (biology)|function]] [[test|tests]] is mainly carried out semi-quantitatively using olfactory bars or bottles kits, which are presented to the patient in order to determine the olfaction thresholds.<ref name="pmid32466862">{{cite journal |vauthors=Lop Gros J, Iglesias Coma M, González Farré M, Serra Pujadas C |title=Olfactory dysfunction in COVID-19, a review of the evidence and implications for pandemic management |journal=Acta Otorrinolaringol Esp |volume= |issue= |pages= |date=May 2020 |pmid=32466862 |doi=10.1016/j.otorri.2020.04.003 |url=}}</ref>
*Some of the most used [[Olfaction|olfactory]] [[Function (biology)|function]] [[test|tests]] are the University of Pennsylvania Smell Identification Test-40 and the Barcelona Smell Test-24, which respectively have 40 and 24 different olfactory stimuli, and are therefore laborious and slow to administer.<ref name="pmid32466862" /><ref name="pmid17882917">{{cite journal |vauthors=Doty RL |title=Office procedures for quantitative assessment of olfactory function |journal=Am J Rhinol |volume=21 |issue=4 |pages=460–73 |date=2007 |pmid=17882917 |doi=10.2500/ajr.2007.21.3043 |url=}}</ref> For large series of patients evaluations the ''4-item Pocket Smell Test'' and the 12-item ''Brief Smell Identification Test'' are prefered.<ref name="pmid32466862" /><ref name="pmid31053960">{{cite journal |vauthors=Joseph T, Auger SD, Peress L, Rack D, Cuzick J, Giovannoni G, Lees A, Schrag AE, Noyce AJ |title=Screening performance of abbreviated versions of the UPSIT smell test |journal=J. Neurol. |volume=266 |issue=8 |pages=1897–1906 |date=August 2019 |pmid=31053960 |pmc=6647236 |doi=10.1007/s00415-019-09340-x |url=}}</ref><br />
*Some of the most used [[Olfaction|olfactory]] [[Function (biology)|function]] [[test|tests]] are the University of Pennsylvania Smell Identification Test-40 and the Barcelona Smell Test-24, which respectively have 40 and 24 different olfactory stimuli, and are therefore laborious and slow to administer.<ref name="pmid32466862" /><ref name="pmid17882917">{{cite journal |vauthors=Doty RL |title=Office procedures for quantitative assessment of olfactory function |journal=Am J Rhinol |volume=21 |issue=4 |pages=460–73 |date=2007 |pmid=17882917 |doi=10.2500/ajr.2007.21.3043 |url=}}</ref> For large series of patients evaluations the ''4-item Pocket Smell Test'' and the 12-item ''Brief Smell Identification Test'' are prefered.<ref name="pmid32466862" /><ref name="pmid31053960">{{cite journal |vauthors=Joseph T, Auger SD, Peress L, Rack D, Cuzick J, Giovannoni G, Lees A, Schrag AE, Noyce AJ |title=Screening performance of abbreviated versions of the UPSIT smell test |journal=J. Neurol. |volume=266 |issue=8 |pages=1897–1906 |date=August 2019 |pmid=31053960 |pmc=6647236 |doi=10.1007/s00415-019-09340-x |url=}}</ref>
*To view the study of choice for diagnosis of COVID-19, click here.<br />


===History and Symptoms===
===History and Symptoms===
Line 195: Line 210:
*[[Anosmia]] occurs more commonly after the onset of other [[symptoms]]. In a study involving 1325 participants with [[anosmia]] (with no confirmatory [[COVID-19 diagnostic study of choice|COVID-19 test]]), 13% reported [[anosmia]] before their onset, 38.4% at the same time, and in 48.6% after the onset of [[symptoms]].<ref name="pmid32277751" />
*[[Anosmia]] occurs more commonly after the onset of other [[symptoms]]. In a study involving 1325 participants with [[anosmia]] (with no confirmatory [[COVID-19 diagnostic study of choice|COVID-19 test]]), 13% reported [[anosmia]] before their onset, 38.4% at the same time, and in 48.6% after the onset of [[symptoms]].<ref name="pmid32277751" />
* A study reports that [[anosmia]] typically developes after 4.4 days of [[COVID-19]] [[infection]].<ref name="pmid323055632">{{cite journal |vauthors=Klopfenstein T, Kadiane-Oussou NJ, Toko L, Royer PY, Lepiller Q, Gendrin V, Zayet S |title=Features of anosmia in COVID-19 |journal=Med Mal Infect |volume= |issue= |pages= |date=April 2020 |pmid=32305563 |pmc=7162775 |doi=10.1016/j.medmal.2020.04.006 |url=}}</ref><ref name="pmid32563019" />
* A study reports that [[anosmia]] typically developes after 4.4 days of [[COVID-19]] [[infection]].<ref name="pmid323055632">{{cite journal |vauthors=Klopfenstein T, Kadiane-Oussou NJ, Toko L, Royer PY, Lepiller Q, Gendrin V, Zayet S |title=Features of anosmia in COVID-19 |journal=Med Mal Infect |volume= |issue= |pages= |date=April 2020 |pmid=32305563 |pmc=7162775 |doi=10.1016/j.medmal.2020.04.006 |url=}}</ref><ref name="pmid32563019" />
*To view the history and symptoms of COVID-19, click here.


===Physical Examination===
===Physical Examination===
Physical examination conductive, sensorineural, or mixed. Clinical evaluation is usually carried out in specialized consultations with kits of different olfactory stimuli that are presented to patients, although if they are not available it may be appropriate to use visual analog scales.<br />
 
* Physical examination using kits of different olfactory stimuli may disclose conductive, sensorineural, or mixed olfactory disfunction.<ref name="pmid32466862" />
* There is no typical physical finding for anosmia related to COVID-19.
* To rule out other conditions physicians may:
 
** Closely inspect the nasal cavity and paranasal sinuses to look for polyps or neoplasms.<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
** Complete a neurological examination for neurodegenerative disorders.<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
** Do a fundoscopy for evidence of raised intracranial pressure due to head trauma.<ref name="urlAnosmia - StatPearls - NCBI Bookshelf" />
** Do skin prick testing for allergic rhinitis.<ref name="urlAnosmia - StatPearls - NCBI Bookshelf">{{cite web |url=https://www.ncbi.nlm.nih.gov/books/NBK482152/ |title=Anosmia - StatPearls - NCBI Bookshelf |format= |work= |accessdate=}}</ref>
* To view the complete physical examination in COVID-19, click here.


===Laboratory Findings===
===Laboratory Findings===


* [[Laboratory diagnosis of virus|Laboratory testing]] and self-isolation should be made in patients who present [[anosmia]], even as a sole [[symptom]].<ref name="pmid32563019" /><br />
* [[Laboratory diagnosis of virus|Laboratory testing]] and self-isolation should be made in patients who present with [[anosmia]], even if this is found as an isolated [[symptom]].<ref name="pmid32563019" />
* To view the laboratory findings on COVID-19, click here.


===Electrocardiogram===
===Electrocardiogram===
<br />
 
* There are no typical electrocardiographic findings for anosmia related to COVID-19.
* To view the electrocardiogram findings on COVID-19, click here.<br />


===X-ray===
===X-ray===
<br />
 
* X-ray imaging to the [[nasal cavity]] and [[sinus]] (Cadwell and Waters projections) does not demonstrate any typical finidings in patients with anosmia due to COVID-19, but may be used to exclude other causes
* To view the x-ray finidings on COVID-19, click here.<br />


===Echocardiography or Ultrasound===
===Echocardiography or Ultrasound===
<br />
 
* There are no typical echocardiographic findings for anosmia related to COVID-19.
* To view the echocardiographic findings on COVID-19, click here.<br />


===CT scan===
===CT scan===


* [[Computed tomography|CT scan]] imaging to the [[nasal cavity]] and [[sinus]] may be used to exclude other causes, for example, a case report that revealed [[Inflammation|inflammatory]] blockage of the olfactory cleft in one patient.<ref name="pmid32563019" />
* [[Computed tomography|CT scan]] imaging to the [[nasal cavity]] and [[sinus]] may be used to exclude other causes, for example, a case report that revealed [[Inflammation|inflammatory]] blockage of the olfactory cleft in one patient.<ref name="pmid32563019" />
*To view the CT scan findings on COVID-19, click here.


===MRI===
===MRI===
<br />
 
* MRI imaging to the [[nasal cavity]] and [[sinus]] does not demonstrate any typical finidings in patients with anosmia due to COVID-19, but may be used to exclude other causes.
* To view the MRI findings on COVID-19, click here.<br />


===Other Imaging Findings===
===Other Imaging Findings===
<br />
 
* Ultrasound imaging to the [[nasal cavity]] and [[sinus]] does not demonstrate any typical finidings in patients with anosmia due to COVID-19, but may be used to exclude other causes.
* To view other imaging findings on COVID-19, click here.<br />


===Other Diagnostic Studies===
===Other Diagnostic Studies===
<br />
 
* To view other diagnostic studies for COVID-19, click here.<br />


==Treatment==
==Treatment==
Line 231: Line 269:
* Olfactory training suggest small to moderate benefit for patients with post-viral [[Olfaction|olfactory]] [[dysfunction]].<ref name="pmid322777512">{{cite journal |vauthors=Hopkins C, Surda P, Kumar N |title=Presentation of new onset anosmia during the COVID-19 pandemic |journal=Rhinology |volume=58 |issue=3 |pages=295–298 |date=June 2020 |pmid=32277751 |doi=10.4193/Rhin20.116 |url=}}</ref>
* Olfactory training suggest small to moderate benefit for patients with post-viral [[Olfaction|olfactory]] [[dysfunction]].<ref name="pmid322777512">{{cite journal |vauthors=Hopkins C, Surda P, Kumar N |title=Presentation of new onset anosmia during the COVID-19 pandemic |journal=Rhinology |volume=58 |issue=3 |pages=295–298 |date=June 2020 |pmid=32277751 |doi=10.4193/Rhin20.116 |url=}}</ref>
* [[Alpha lipoic acid]],<ref name="pmid12439184">{{cite journal |vauthors=Hummel T, Heilmann S, Hüttenbriuk KB |title=Lipoic acid in the treatment of smell dysfunction following viral infection of the upper respiratory tract |journal=Laryngoscope |volume=112 |issue=11 |pages=2076–80 |date=November 2002 |pmid=12439184 |doi=10.1097/00005537-200211000-00031 |url=}}</ref> [[omega-3]] supplementation,<ref name="pmid319501562">{{cite journal |vauthors=Yan CH, Rathor A, Krook K, Ma Y, Rotella MR, Dodd RL, Hwang PH, Nayak JV, Oyesiku NM, DelGaudio JM, Levy JM, Wise J, Wise SK, Patel ZM |title=Effect of Omega-3 Supplementation in Patients With Smell Dysfunction Following Endoscopic Sellar and Parasellar Tumor Resection: A Multicenter Prospective Randomized Controlled Trial |journal=Neurosurgery |volume= |issue= |pages= |date=January 2020 |pmid=31950156 |doi=10.1093/neuros/nyz559 |url=}}</ref> and intranasal [[Vitamin A derivatives|vitamin A]]<ref name="pmid28040824">{{cite journal |vauthors=Sorokowska A, Drechsler E, Karwowski M, Hummel T |title=Effects of olfactory training: a meta-analysis |journal=Rhinology |volume=55 |issue=1 |pages=17–26 |date=March 2017 |pmid=28040824 |doi=10.4193/Rhin16.195 |url=}}</ref> have been shown to improve objective tests of [[Olfaction|olfactory]] recovery in a small uncontrolled studies of patients with [[COVID-19]] related [[anosmia]], although, further investigation is needed before these therapies can be widely recomended.<ref name="pmid322777512" />
* [[Alpha lipoic acid]],<ref name="pmid12439184">{{cite journal |vauthors=Hummel T, Heilmann S, Hüttenbriuk KB |title=Lipoic acid in the treatment of smell dysfunction following viral infection of the upper respiratory tract |journal=Laryngoscope |volume=112 |issue=11 |pages=2076–80 |date=November 2002 |pmid=12439184 |doi=10.1097/00005537-200211000-00031 |url=}}</ref> [[omega-3]] supplementation,<ref name="pmid319501562">{{cite journal |vauthors=Yan CH, Rathor A, Krook K, Ma Y, Rotella MR, Dodd RL, Hwang PH, Nayak JV, Oyesiku NM, DelGaudio JM, Levy JM, Wise J, Wise SK, Patel ZM |title=Effect of Omega-3 Supplementation in Patients With Smell Dysfunction Following Endoscopic Sellar and Parasellar Tumor Resection: A Multicenter Prospective Randomized Controlled Trial |journal=Neurosurgery |volume= |issue= |pages= |date=January 2020 |pmid=31950156 |doi=10.1093/neuros/nyz559 |url=}}</ref> and intranasal [[Vitamin A derivatives|vitamin A]]<ref name="pmid28040824">{{cite journal |vauthors=Sorokowska A, Drechsler E, Karwowski M, Hummel T |title=Effects of olfactory training: a meta-analysis |journal=Rhinology |volume=55 |issue=1 |pages=17–26 |date=March 2017 |pmid=28040824 |doi=10.4193/Rhin16.195 |url=}}</ref> have been shown to improve objective tests of [[Olfaction|olfactory]] recovery in a small uncontrolled studies of patients with [[COVID-19]] related [[anosmia]], although, further investigation is needed before these therapies can be widely recomended.<ref name="pmid322777512" />
*The main problem for the study of [[anosmia]] related to [[COVID-19]] treatment is that the majority of patients do not give importance to this symptom and recover spontaneously, without medical attention, so little evidence to support pharmacotherapy exists.<ref name="pmid32466862" /><ref name="pmid15563908">{{cite journal |vauthors=Seiden AM |title=Postviral olfactory loss |journal=Otolaryngol. Clin. North Am. |volume=37 |issue=6 |pages=1159–66 |date=December 2004 |pmid=15563908 |doi=10.1016/j.otc.2004.06.007 |url=}}</ref><br />
*The main problem for the study of [[anosmia]] related to [[COVID-19]] treatment is that the majority of patients do not give importance to this symptom and recover spontaneously, without medical attention, so little evidence to support pharmacotherapy exists.<ref name="pmid32466862" /><ref name="pmid15563908">{{cite journal |vauthors=Seiden AM |title=Postviral olfactory loss |journal=Otolaryngol. Clin. North Am. |volume=37 |issue=6 |pages=1159–66 |date=December 2004 |pmid=15563908 |doi=10.1016/j.otc.2004.06.007 |url=}}</ref>
*To view medical treatment for COVID-19, click here.


===Surgery===
===Surgery===
<br />
 
* There are no surgical procedures for [[anosmia]] related to [[COVID-19]].<br />


===Primary Prevention===
===Primary Prevention===

Revision as of 04:01, 6 July 2020

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Moises Romo M.D.

Synonyms and keywords:anosmia, olfactory dysfunction, SARS-CoV-2, dysgeusia

Overview

Total or parcial loss of olfactory function (anosmia/hyposmia) has been formally recognized as a characteristic symptom of COVID-19 infection, and may be the most common sign of infection due to this virus.[1]

Anosmia may appear without any other symptoms or signs in patients with COVID-19 infection.[2]

The extent of potential olfactory dysfunction due to COVID-19 is still unclear.[3]

To view the complete page of COVID-19, click here.

Historical Perspective

Classification

Pathophysiology

Causes


Differentiating COVID-19-associated anosmia from other Diseases

  • When differentiating anosmia due to COVID-19 infection from other causes, it is important to pay attention into the presentation:
    • Acute smell loss (other upper respiratory viral infections, head injuries).[21]
    • Chronic smell loss (normal aging, rhinitis, nasal polyps, neoplasms, neurodegenerative disorders).[21]
    • Intermittent smell loss (allergic rhinitis, use of topical drugs).[21]
    • Congenital smell loss (Kallmann syndrome).[21]
  • To view the differential diagnosis of COVID-19, click here.

Epidemiology and Demographics

Prevalence of anosmia in patients with COVID-19[3]
Date of publication Country Author Number of patients Prevalence
March 26, 2020 Italy Giacomelli et al.[25] 59 33.9%
March 27, 2020 Iran Bagheri et al.[26] 10,069 48.23%
April 1, 2020 Italy Vaira et al.[27] 320 19.4%
April 6, 2020 European countries Lechien et al.[28] 417 85.6%
April 7, 2020 United Kingdom Menni et al.[29] 579 59.41%
April 12, 2020 United States Yan et al.[30] 59 68%
April 16, 2020 France Klopfenstein et al.[31] 47 47%
April 17, 2020 Iran Moein et al.[4] 60 98.33%
April 22, 2020 United Kingdom Spinato et al.[32] 202 64.4%
April 22, 2020 Iran Heidari et al.[33] 23 69.57%
April 22, 2020 Spain Beltran-Corbellini et al.[34] 79 31.65%
April 24, 2020 United States Yan et al.[35] 169 75.7%
May 1, 2020 Germany Luers et al.[36] 72 74%
May 1, 2020 Italy Vaira et al.[37] 33 75.8%
  • To view screening for COVID-19, click here.

Risk Factors

Screening

  • A screening strategy, duly validated for olfactory disfunction in COVID-19, consists of carrying out specific questionnaires, such as the Questionnaire for Olfactory Disfunction.[7][41][42]
  • Several ENT societies in the United Kingdom and the United States, have advised to treat anosmia marker of SARS-CoV-2 infection.[43][44][45]
  • The American Academy of Otolaryngology (AAO) proposed for anosmia, hyposmia, and dysgeusia to be added to the list of screening tools for COVID-19 in otherwise asymptomatic individuals.[45][43]
  • In the absence of available solid data, the recommendation should be to perform nasal swabs on any patient with recent onset anosmia, duly assessed.[7]
  • To view screening for COVID-19, click here.

Natural History, Complications, and Prognosis

  • Anosmia related to COVID-19, typically has a duration of 8.96 days.[3][46]
  • Approximately 82% of patients with anosmia related to COVID-19 recover within 2 weeks and 98% of them within 28 days.[3][46][47]
  • The intensity and duration of the olfactory disfunction associated to COVID-19, is highly variable depending on the capacity and rate of regeneration of the neuroeptielium.[7]
  • To view natural history, complications, and prognosis of COVID-19, click here.

Diagnosis

Diagnostic Study of Choice

  • Olfactory function test (OFT) has been the study of choice for diagnosis of anosmia and olfactory dysfunction.[48][3][4][49]
  • In many studies, full olfactory function tests have been disregarded.[3]
  • Olfactory function tests is mainly carried out semi-quantitatively using olfactory bars or bottles kits, which are presented to the patient in order to determine the olfaction thresholds.[7]
  • Some of the most used olfactory function tests are the University of Pennsylvania Smell Identification Test-40 and the Barcelona Smell Test-24, which respectively have 40 and 24 different olfactory stimuli, and are therefore laborious and slow to administer.[7][50] For large series of patients evaluations the 4-item Pocket Smell Test and the 12-item Brief Smell Identification Test are prefered.[7][51]
  • To view the study of choice for diagnosis of COVID-19, click here.

History and Symptoms

  • Anosmia may occur suddenly as the only symptom of COVID-19 in approximately 16% of individuals.[1][53]
  • In a study, 74.4% reported complete loss of smell.[1]
  • Anosmia occurs more commonly after the onset of other symptoms. In a study involving 1325 participants with anosmia (with no confirmatory COVID-19 test), 13% reported anosmia before their onset, 38.4% at the same time, and in 48.6% after the onset of symptoms.[1]
  • A study reports that anosmia typically developes after 4.4 days of COVID-19 infection.[46][3]
  • To view the history and symptoms of COVID-19, click here.

Physical Examination

  • Physical examination using kits of different olfactory stimuli may disclose conductive, sensorineural, or mixed olfactory disfunction.[7]
  • There is no typical physical finding for anosmia related to COVID-19.
  • To rule out other conditions physicians may:
    • Closely inspect the nasal cavity and paranasal sinuses to look for polyps or neoplasms.[21]
    • Complete a neurological examination for neurodegenerative disorders.[21]
    • Do a fundoscopy for evidence of raised intracranial pressure due to head trauma.[21]
    • Do skin prick testing for allergic rhinitis.[21]
  • To view the complete physical examination in COVID-19, click here.

Laboratory Findings

  • Laboratory testing and self-isolation should be made in patients who present with anosmia, even if this is found as an isolated symptom.[3]
  • To view the laboratory findings on COVID-19, click here.

Electrocardiogram

  • There are no typical electrocardiographic findings for anosmia related to COVID-19.
  • To view the electrocardiogram findings on COVID-19, click here.

X-ray

  • X-ray imaging to the nasal cavity and sinus (Cadwell and Waters projections) does not demonstrate any typical finidings in patients with anosmia due to COVID-19, but may be used to exclude other causes
  • To view the x-ray finidings on COVID-19, click here.

Echocardiography or Ultrasound

  • There are no typical echocardiographic findings for anosmia related to COVID-19.
  • To view the echocardiographic findings on COVID-19, click here.

CT scan

  • CT scan imaging to the nasal cavity and sinus may be used to exclude other causes, for example, a case report that revealed inflammatory blockage of the olfactory cleft in one patient.[3]
  • To view the CT scan findings on COVID-19, click here.

MRI

  • MRI imaging to the nasal cavity and sinus does not demonstrate any typical finidings in patients with anosmia due to COVID-19, but may be used to exclude other causes.
  • To view the MRI findings on COVID-19, click here.

Other Imaging Findings

  • Ultrasound imaging to the nasal cavity and sinus does not demonstrate any typical finidings in patients with anosmia due to COVID-19, but may be used to exclude other causes.
  • To view other imaging findings on COVID-19, click here.

Other Diagnostic Studies

  • To view other diagnostic studies for COVID-19, click here.

Treatment

Medical Therapy

  • Oral steroids may be used in patients with anosmia related to COVID-19, when duration exceeds 2 weeks.[2]
  • Olfactory training suggest small to moderate benefit for patients with post-viral olfactory dysfunction.[2]
  • Alpha lipoic acid,[54] omega-3 supplementation,[55] and intranasal vitamin A[56] have been shown to improve objective tests of olfactory recovery in a small uncontrolled studies of patients with COVID-19 related anosmia, although, further investigation is needed before these therapies can be widely recomended.[2]
  • The main problem for the study of anosmia related to COVID-19 treatment is that the majority of patients do not give importance to this symptom and recover spontaneously, without medical attention, so little evidence to support pharmacotherapy exists.[7][57]
  • To view medical treatment for COVID-19, click here.

Surgery

Primary Prevention

Secondary Prevention


References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Hopkins C, Surda P, Kumar N (June 2020). "Presentation of new onset anosmia during the COVID-19 pandemic". Rhinology. 58 (3): 295–298. doi:10.4193/Rhin20.116. PMID 32277751 Check |pmid= value (help).
  2. ↑ 2.0 2.1 2.2 2.3 Hopkins C, Surda P, Kumar N (June 2020). "Presentation of new onset anosmia during the COVID-19 pandemic". Rhinology. 58 (3): 295–298. doi:10.4193/Rhin20.116. PMID 32277751 Check |pmid= value (help).
  3. ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 3.21 3.22 Meng X, Deng Y, Dai Z, Meng Z (June 2020). "COVID-19 and anosmia: A review based on up-to-date knowledge". Am J Otolaryngol. 41 (5): 102581. doi:10.1016/j.amjoto.2020.102581. PMC 7265845 Check |pmc= value (help). PMID 32563019 Check |pmid= value (help).
  4. ↑ 4.0 4.1 4.2 Moein, Shima T.; Hashemian, Seyed MohammadReza; Mansourafshar, Babak; Khorram‐Tousi, Ali; Tabarsi, Payam; Doty, Richard L. (2020). "Smell dysfunction: a biomarker for COVID‐19". International Forum of Allergy & Rhinology. doi:10.1002/alr.22587. ISSN 2042-6976.
  5. ↑ "[2004.09338] Augmented Curation of Unstructured Clinical Notes from a Massive EHR System Reveals Specific Phenotypic Signature of Impending COVID-19 Diagnosis".
  6. ↑ Beltrán‐Corbellini, Á.; Chico‐García, J. L.; Martínez‐Poles, J.; Rodríguez‐Jorge, F.; Natera‐Villalba, E.; Gómez‐Corral, J.; Gómez‐López, A.; Monreal, E.; Parra‐Díaz, P.; Cortés‐Cuevas, J. L.; Galán, J. C.; Fragola‐Arnau, C.; Porta‐Etessam, J.; Masjuan, J.; Alonso‐Cánovas, A. (2020). "Acute‐onset smell and taste disorders in the context of COVID‐19: a pilot multicentre polymerase chain reaction based case–control study". European Journal of Neurology. doi:10.1111/ene.14273. ISSN 1351-5101.
  7. ↑ 7.00 7.01 7.02 7.03 7.04 7.05 7.06 7.07 7.08 7.09 7.10 7.11 7.12 Lop Gros J, Iglesias Coma M, González Farré M, Serra Pujadas C (May 2020). "Olfactory dysfunction in COVID-19, a review of the evidence and implications for pandemic management". Acta Otorrinolaringol Esp. doi:10.1016/j.otorri.2020.04.003. PMID 32466862 Check |pmid= value (help).
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  15. ↑ Capelli, Marco; Gatti, Patrizia (2020). "Anosmia and COVID-19 in south Lombardy: description of the first cases series in Europe". B-ENT. 16 (1): 86–90. doi:10.5152/B-ENT.2020.20129. ISSN 2684-4907.
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  19. ↑ Suzuki M, Saito K, Min WP, Vladau C, Toida K, Itoh H, Murakami S (February 2007). "Identification of viruses in patients with postviral olfactory dysfunction". Laryngoscope. 117 (2): 272–7. doi:10.1097/01.mlg.0000249922.37381.1e. PMC 7165544 Check |pmc= value (help). PMID 17277621.
  20. ↑ Eccles R (November 2005). "Understanding the symptoms of the common cold and influenza". Lancet Infect Dis. 5 (11): 718–25. doi:10.1016/S1473-3099(05)70270-X. PMC 7185637 Check |pmc= value (help). PMID 16253889.
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  25. ↑ Giacomelli A, Pezzati L, Conti F, Bernacchia D, Siano M, Oreni L, Rusconi S, Gervasoni C, Ridolfo AL, Rizzardini G, Antinori S, Galli M (March 2020). "Self-reported olfactory and taste disorders in SARS-CoV-2 patients: a cross-sectional study". Clin. Infect. Dis. doi:10.1093/cid/ciaa330. PMC 7184514 Check |pmc= value (help). PMID 32215618 Check |pmid= value (help).
  26. ↑ Bagheri, Seyed Hamid Reza; Asghari, Ali Mohammad; Farhadi, Mohammad; Shamshiri, Ahmad Reza; Kabir, Ali; Kamrava, Seyed Kamran; Jalessi, Maryam; Mohebbi, Alireza; Alizadeh, Rafieh; Honarmand, Ali Asghar; Ghalehbaghi, Babak; Salimi, Alireza (2020). doi:10.1101/2020.03.23.20041889. Missing or empty |title= (help)
  27. ↑ Vaira LA, Salzano G, Deiana G, De Riu G (July 2020). "Anosmia and Ageusia: Common Findings in COVID-19 Patients". Laryngoscope. 130 (7): 1787. doi:10.1002/lary.28692. PMC 7228304 Check |pmc= value (help). PMID 32237238 Check |pmid= value (help).
  28. ↑ Lechien JR, Chiesa-Estomba CM, De Siati DR, Horoi M, Le Bon SD, Rodriguez A, Dequanter D, Blecic S, El Afia F, Distinguin L, Chekkoury-Idrissi Y, Hans S, Delgado IL, Calvo-Henriquez C, Lavigne P, Falanga C, Barillari MR, Cammaroto G, Khalife M, Leich P, Souchay C, Rossi C, Journe F, Hsieh J, Edjlali M, Carlier R, Ris L, Lovato A, De Filippis C, Coppee F, Fakhry N, Ayad T, Saussez S (April 2020). "Olfactory and gustatory dysfunctions as a clinical presentation of mild-to-moderate forms of the coronavirus disease (COVID-19): a multicenter European study". Eur Arch Otorhinolaryngol. doi:10.1007/s00405-020-05965-1. PMC 7134551 Check |pmc= value (help). PMID 32253535 Check |pmid= value (help).
  29. ↑ Menni, Cristina; Valdes, Ana; Freydin, Maxim B; Ganesh, Sajaysurya; El-Sayed Moustafa, Julia; Visconti, Alessia; Hysi, Pirro; Bowyer, Ruth C E; Mangino, Massimo; Falchi, Mario; Wolf, Jonathan; Steves, Claire; Spector, Tim (2020). doi:10.1101/2020.04.05.20048421. Missing or empty |title= (help)
  30. ↑ Yan CH, Faraji F, Prajapati DP, Boone CE, DeConde AS (April 2020). "Association of chemosensory dysfunction and COVID-19 in patients presenting with influenza-like symptoms". Int Forum Allergy Rhinol. doi:10.1002/alr.22579. PMC 7262089 Check |pmc= value (help). PMID 32279441 Check |pmid= value (help).
  31. ↑ Klopfenstein, T.; Kadiane-Oussou, N.J.; Toko, L.; Royer, P.-Y.; Lepiller, Q.; Gendrin, V.; Zayet, S. (2020). "Features of anosmia in COVID-19". Médecine et Maladies Infectieuses. doi:10.1016/j.medmal.2020.04.006. ISSN 0399-077X.
  32. ↑ Spinato, Giacomo; Fabbris, Cristoforo; Polesel, Jerry; Cazzador, Diego; Borsetto, Daniele; Hopkins, Claire; Boscolo-Rizzo, Paolo (2020). "Alterations in Smell or Taste in Mildly Symptomatic Outpatients With SARS-CoV-2 Infection". JAMA. 323 (20): 2089. doi:10.1001/jama.2020.6771. ISSN 0098-7484.
  33. ↑ Heidari, F.; Karimi, E.; Firouzifar, M.; Khamushian, P.; Ansari, R.; Mohammadi Ardehali, M.; Heidari, F. (2020). "Anosmia as a Prominent Symptom of COVID-19 Infection". Rhinology journal. 58 (3): 302–303. doi:10.4193/Rhin20.140. ISSN 0300-0729.
  34. ↑ Beltrán‐Corbellini, Á.; Chico‐García, J. L.; Martínez‐Poles, J.; Rodríguez‐Jorge, F.; Natera‐Villalba, E.; Gómez‐Corral, J.; Gómez‐López, A.; Monreal, E.; Parra‐Díaz, P.; Cortés‐Cuevas, J. L.; Galán, J. C.; Fragola‐Arnau, C.; Porta‐Etessam, J.; Masjuan, J.; Alonso‐Cánovas, A. (2020). "Acute‐onset smell and taste disorders in the context of COVID‐19: a pilot multicentre polymerase chain reaction based case–control study". European Journal of Neurology. doi:10.1111/ene.14273. ISSN 1351-5101.
  35. ↑ Yan, Carol H.; Faraji, Farhoud; Prajapati, Divya P.; Ostrander, Benjamin T.; DeConde, Adam S. (2020). "Self‐reported olfactory loss associates with outpatient clinical course in COVID‐19". International Forum of Allergy & Rhinology. doi:10.1002/alr.22592. ISSN 2042-6976.
  36. ↑ Heindl, Ludwig M; Lehmann, Clara; Klein, Florian; Dewald, Felix; Augustin, Max; Wawer Matos, Philomena A; Loreck, Niklas; Rokohl, Alexander C; Luers, Jan C (2020). "Olfactory and Gustatory Dysfunction in Coronavirus Disease 19 (COVID-19)". Clinical Infectious Diseases. doi:10.1093/cid/ciaa525. ISSN 1058-4838.
  37. ↑ Vaira, Luigi Angelo; Salzano, Giovanni; Petrocelli, Marzia; Deiana, Giovanna; Salzano, Francesco Antonio; De Riu, Giacomo (2020). "Validation of a self-administered olfactory and gustatory test for the remotely evaluation of COVID-19 patients in home quarantine". Head & Neck. doi:10.1002/hed.26228. ISSN 1043-3074.
  38. ↑ 38.0 38.1 Stogbauer J, Wirkner K, Engel C, Moebus S, Pundt N, Teismann H, Loffler M, Hummel T, Beule AG, Berger K (April 2020). "Prevalence and risk factors of smell dysfunction - a comparison between five German population-based studies". Rhinology. 58 (2): 184–191. doi:10.4193/Rhin19.181. PMID 31693018.
  39. ↑ 39.0 39.1 Wang X, Zhang C, Xia X, Yang Y, Zhou C (October 2019). "Effect of gender on odor identification at different life stages: a meta-analysis". Rhinology. 57 (5): 322–330. doi:10.4193/Rhin19.005. PMID 31152646.
  40. ↑ Williams, Frances MK; Freydin, Maxim; Mangino, Massimo; Couvreur, Simon; Visconti, Alessia; Bowyer, Ruth CE; Le Roy, Caroline I; Falchi, Mario; Sudre, Carole; Davies, Richard; Hammond, Christopher; Menni, Cristina; Steves, Claire; Spector, Tim (2020). doi:10.1101/2020.04.22.20072124. Missing or empty |title= (help)
  41. ↑ Nguyen DT, Rumeau C, Gallet P, Jankowski R (April 2016). "Olfactory exploration: State of the art". Eur Ann Otorhinolaryngol Head Neck Dis. 133 (2): 113–8. doi:10.1016/j.anorl.2015.08.038. PMID 26384780.
  42. ↑ Simopoulos E, Katotomichelakis M, Gouveris H, Tripsianis G, Livaditis M, Danielides V (July 2012). "Olfaction-associated quality of life in chronic rhinosinusitis: adaptation and validation of an olfaction-specific questionnaire". Laryngoscope. 122 (7): 1450–4. doi:10.1002/lary.23349. PMID 22566102.
  43. ↑ 43.0 43.1 Robert Pellegrin, Keiland W. Cooper, Antonella Di Pizio, Paule V. Joseph, Surabhi Bhutani, Valentina Parma (2020). "Corona Viruses and the Chemical Senses: Past, Present, and Future". Oxford University. line feed character in |title= at position 40 (help)
  44. ↑ "www.entuk.org" (PDF).
  45. ↑ 45.0 45.1 "AAO-HNSF 2020 Annual Meeting & OTO Experience | American Academy of Otolaryngology-Head and Neck Surgery".
  46. ↑ 46.0 46.1 46.2 Klopfenstein T, Kadiane-Oussou NJ, Toko L, Royer PY, Lepiller Q, Gendrin V, Zayet S (April 2020). "Features of anosmia in COVID-19". Med Mal Infect. doi:10.1016/j.medmal.2020.04.006. PMC 7162775 Check |pmc= value (help). PMID 32305563 Check |pmid= value (help).
  47. ↑ Yan CH, Faraji F, Prajapati DP, Boone CE, DeConde AS (April 2020). "Association of chemosensory dysfunction and COVID-19 in patients presenting with influenza-like symptoms". Int Forum Allergy Rhinol. doi:10.1002/alr.22579. PMC 7262089 Check |pmc= value (help). PMID 32279441 Check |pmid= value (help).
  48. ↑ Ottaviano, G.; Carecchio, M.; Scarpa, B.; Marchese-Ragona, R. (2020). "Olfactory and rhinological evaluations in SARS-CoV-2 patients complaining of olfactory loss". Rhinology journal. 0 (0): 0–0. doi:10.4193/Rhin20.136. ISSN 0300-0729.
  49. ↑ Vaira, Luigi Angelo; Salzano, Giovanni; Petrocelli, Marzia; Deiana, Giovanna; Salzano, Francesco Antonio; De Riu, Giacomo (2020). "Validation of a self-administered olfactory and gustatory test for the remotely evaluation of COVID-19 patients in home quarantine". Head & Neck. doi:10.1002/hed.26228. ISSN 1043-3074.
  50. ↑ Doty RL (2007). "Office procedures for quantitative assessment of olfactory function". Am J Rhinol. 21 (4): 460–73. doi:10.2500/ajr.2007.21.3043. PMID 17882917.
  51. ↑ Joseph T, Auger SD, Peress L, Rack D, Cuzick J, Giovannoni G, Lees A, Schrag AE, Noyce AJ (August 2019). "Screening performance of abbreviated versions of the UPSIT smell test". J. Neurol. 266 (8): 1897–1906. doi:10.1007/s00415-019-09340-x. PMC 6647236 Check |pmc= value (help). PMID 31053960.
  52. ↑ "Neue Corona-Symptome entdeckt: Virologe Hendrik Streeck zum Virus".
  53. ↑ Heidari F, Karimi E, Firouzifar M, Khamushian P, Ansari R, Mohammadi Ardehali M, Heidari F (June 2020). "Anosmia as a prominent symptom of COVID-19 infection". Rhinology. 58 (3): 302–303. doi:10.4193/Rhin20.140. PMID 32319971 Check |pmid= value (help).
  54. ↑ Hummel T, Heilmann S, Hüttenbriuk KB (November 2002). "Lipoic acid in the treatment of smell dysfunction following viral infection of the upper respiratory tract". Laryngoscope. 112 (11): 2076–80. doi:10.1097/00005537-200211000-00031. PMID 12439184.
  55. ↑ Yan CH, Rathor A, Krook K, Ma Y, Rotella MR, Dodd RL, Hwang PH, Nayak JV, Oyesiku NM, DelGaudio JM, Levy JM, Wise J, Wise SK, Patel ZM (January 2020). "Effect of Omega-3 Supplementation in Patients With Smell Dysfunction Following Endoscopic Sellar and Parasellar Tumor Resection: A Multicenter Prospective Randomized Controlled Trial". Neurosurgery. doi:10.1093/neuros/nyz559. PMID 31950156.
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  57. ↑ Seiden AM (December 2004). "Postviral olfactory loss". Otolaryngol. Clin. North Am. 37 (6): 1159–66. doi:10.1016/j.otc.2004.06.007. PMID 15563908.
  58. ↑ Meng, Xiangming; Dai, Zhiyong; Hang, Chao; Wang, Yangyang (2020). "Smartphone-enabled wireless otoscope-assisted online telemedicine during the COVID-19 outbreak". American Journal of Otolaryngology. 41 (3): 102476. doi:10.1016/j.amjoto.2020.102476. ISSN 0196-0709.
  59. ↑ Vaira, Luigi Angelo; Salzano, Giovanni; Petrocelli, Marzia; Deiana, Giovanna; Salzano, Francesco Antonio; De Riu, Giacomo (2020). "Validation of a self-administered olfactory and gustatory test for the remotely evaluation of COVID-19 patients in home quarantine". Head & Neck. doi:10.1002/hed.26228. ISSN 1043-3074.


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