COVID-19-associated anosmia: Difference between revisions

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==Classification==
==Classification==


* There is no established system for the classification of [[COVID-19]] associated [[anosmia]].
* In general, olfactory dysfunction can be classified as:
**Anosmia. Total incapacity for odor detection.<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" />
**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" />
*There is no established system for the classification of [[COVID-19]] associated [[anosmia]].


==Pathophysiology==
==Pathophysiology==
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* The most common identified [[risk factors]] for developing [[anosmia]] in patients with [[COVID-19]] infection are:<ref name="pmid32277751" /><ref name="pmid31693018">{{cite journal |vauthors=Stogbauer J, Wirkner K, Engel C, Moebus S, Pundt N, Teismann H, Loffler M, Hummel T, Beule AG, Berger K |title=Prevalence and risk factors of smell dysfunction - a comparison between five German population-based studies |journal=Rhinology |volume=58 |issue=2 |pages=184–191 |date=April 2020 |pmid=31693018 |doi=10.4193/Rhin19.181 |url=}}</ref><ref name="pmid31152646">{{cite journal |vauthors=Wang X, Zhang C, Xia X, Yang Y, Zhou C |title=Effect of gender on odor identification at different life stages: a meta-analysis |journal=Rhinology |volume=57 |issue=5 |pages=322–330 |date=October 2019 |pmid=31152646 |doi=10.4193/Rhin19.005 |url=}}</ref>
* The most common identified [[risk factors]] for developing [[anosmia]] in patients with [[COVID-19]] infection are:<ref name="pmid32277751" /><ref name="pmid31693018">{{cite journal |vauthors=Stogbauer J, Wirkner K, Engel C, Moebus S, Pundt N, Teismann H, Loffler M, Hummel T, Beule AG, Berger K |title=Prevalence and risk factors of smell dysfunction - a comparison between five German population-based studies |journal=Rhinology |volume=58 |issue=2 |pages=184–191 |date=April 2020 |pmid=31693018 |doi=10.4193/Rhin19.181 |url=}}</ref><ref name="pmid31152646">{{cite journal |vauthors=Wang X, Zhang C, Xia X, Yang Y, Zhou C |title=Effect of gender on odor identification at different life stages: a meta-analysis |journal=Rhinology |volume=57 |issue=5 |pages=322–330 |date=October 2019 |pmid=31152646 |doi=10.4193/Rhin19.005 |url=}}</ref>
** Advanced [[age]]<ref name="pmid31693018" />
** Advanced [[age]]<ref name="pmid31693018" />
**[[Male]] gender<ref name="pmid31152646" />
**[[Male|Female]] gender<ref name="pmid31152646" /><ref name="pmid32466862" />
**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>
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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>


<br />
<br />
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* [[Anosmia]] related to [[COVID-19]], typically has a duration of 8.96 days.<ref name="pmid32563019" /><ref name="pmid323055632" />
* [[Anosmia]] related to [[COVID-19]], typically has a duration of 8.96 days.<ref name="pmid32563019" /><ref name="pmid323055632" />
* 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" />


==Diagnosis==
==Diagnosis==
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* [[Olfaction|Olfactory]] [[Function (biology)|function]] [[test]] (OFT) has been the study of choice for diagnosis of [[anosmia]] and [[olfactory]] [[dysfunction]].<ref name="OttavianoCarecchio2020">{{cite journal|last1=Ottaviano|first1=G.|last2=Carecchio|first2=M.|last3=Scarpa|first3=B.|last4=Marchese-Ragona|first4=R.|title=Olfactory and rhinological evaluations in SARS-CoV-2 patients complaining of olfactory loss|journal=Rhinology journal|volume=0|issue=0|year=2020|pages=0–0|issn=03000729|doi=10.4193/Rhin20.136}}</ref><ref name="pmid32563019" /><ref name="MoeinHashemian20202" /><ref name="VairaSalzano20202">{{cite journal|last1=Vaira|first1=Luigi Angelo|last2=Salzano|first2=Giovanni|last3=Petrocelli|first3=Marzia|last4=Deiana|first4=Giovanna|last5=Salzano|first5=Francesco Antonio|last6=De Riu|first6=Giacomo|title=Validation of a self-administered olfactory and gustatory test for the remotely evaluation of COVID-19 patients in home quarantine|journal=Head & Neck|year=2020|issn=10433074|doi=10.1002/hed.26228}}</ref>
* [[Olfaction|Olfactory]] [[Function (biology)|function]] [[test]] (OFT) has been the study of choice for diagnosis of [[anosmia]] and [[olfactory]] [[dysfunction]].<ref name="OttavianoCarecchio2020">{{cite journal|last1=Ottaviano|first1=G.|last2=Carecchio|first2=M.|last3=Scarpa|first3=B.|last4=Marchese-Ragona|first4=R.|title=Olfactory and rhinological evaluations in SARS-CoV-2 patients complaining of olfactory loss|journal=Rhinology journal|volume=0|issue=0|year=2020|pages=0–0|issn=03000729|doi=10.4193/Rhin20.136}}</ref><ref name="pmid32563019" /><ref name="MoeinHashemian20202" /><ref name="VairaSalzano20202">{{cite journal|last1=Vaira|first1=Luigi Angelo|last2=Salzano|first2=Giovanni|last3=Petrocelli|first3=Marzia|last4=Deiana|first4=Giovanna|last5=Salzano|first5=Francesco Antonio|last6=De Riu|first6=Giacomo|title=Validation of a self-administered olfactory and gustatory test for the remotely evaluation of COVID-19 patients in home quarantine|journal=Head & Neck|year=2020|issn=10433074|doi=10.1002/hed.26228}}</ref>
* In many studies, full [[Olfaction|olfactory]] [[Function (biology)|function]] tests have been disregarded.<ref name="pmid32563019" /><br />
* 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>
*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 />


===History and Symptoms===
===History and Symptoms===
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===Physical Examination===
===Physical Examination===
<br />
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 />


===Laboratory Findings===
===Laboratory Findings===
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* [[Oral steroids]] may be used in patients with [[anosmia]] related to [[COVID-19]], when duration exceeds 2 weeks.<ref name="pmid322777512" />
* [[Oral steroids]] may be used in patients with [[anosmia]] related to [[COVID-19]], when duration exceeds 2 weeks.<ref name="pmid322777512" />
* 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" /><br />
* [[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 />


===Surgery===
===Surgery===

Revision as of 02:26, 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]

Historical Perspective

Classification

  • In general, olfactory dysfunction can be classified as:
    • Anosmia. Total incapacity for odor detection.[7]
    • Hyposmia.Increased odor detection threshold. This is the most common type of olfactory dysfunction in patients with COVID-19.[7]
    • Hyperosmia.Decreased odor detection threshold.[7]
    • 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).[7]
  • There is no established system for the classification of COVID-19 associated anosmia.

Pathophysiology

Causes


Differentiating COVID-19-associated anosmia from other Diseases

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.[23] 59 33.9%
March 27, 2020 Iran Bagheri et al.[24] 10,069 48.23%
April 1, 2020 Italy Vaira et al.[25] 320 19.4%
April 6, 2020 European countries Lechien et al.[26] 417 85.6%
April 7, 2020 United Kingdom Menni et al.[27] 579 59.41%
April 12, 2020 United States Yan et al.[28] 59 68%
April 16, 2020 France Klopfenstein et al.[29] 47 47%
April 17, 2020 Iran Moein et al.[4] 60 98.33%
April 22, 2020 United Kingdom Spinato et al.[30] 202 64.4%
April 22, 2020 Iran Heidari et al.[31] 23 69.57%
April 22, 2020 Spain Beltran-Corbellini et al.[32] 79 31.65%
April 24, 2020 United States Yan et al.[33] 169 75.7%
May 1, 2020 Germany Luers et al.[34] 72 74%
May 1, 2020 Italy Vaira et al.[35] 33 75.8%


Risk Factors

Screening


Natural History, Complications, and Prognosis

  • Anosmia related to COVID-19, typically has a duration of 8.96 days.[3][44]
  • Approximately 82% of patients with anosmia related to COVID-19 recover within 2 weeks and 98% of them within 28 days.[3][44][45]
  • 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]

Diagnosis

Diagnostic Study of Choice

  • Olfactory function test (OFT) has been the study of choice for diagnosis of anosmia and olfactory dysfunction.[46][3][4][47]
  • 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][48] For large series of patients evaluations the 4-item Pocket Smell Test and the 12-item Brief Smell Identification Test are prefered.[7][49]

History and Symptoms

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.

Laboratory Findings

Electrocardiogram


X-ray


Echocardiography or Ultrasound


CT scan

MRI


Other Imaging Findings


Other Diagnostic Studies


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,[52] omega-3 supplementation,[53] and intranasal vitamin A[54] 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][55]

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 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).
  8. ↑ Hummel T, Whitcroft KL, Andrews P, Altundag A, Cinghi C, Costanzo RM, Damm M, Frasnelli J, Gudziol H, Gupta N, Haehne A, Holbrook E, Hong SC, Hornung D, Hüttenbrink KB, Kamel R, Kobayashi M, Konstantinidis I, Landis BN, Leopold DA, Macchi A, Miwa T, Moesges R, Mullol J, Mueller CA, Ottaviano G, Passali GC, Philpott C, Pinto JM, Ramakrishnan VJ, Rombaux P, Roth Y, Schlosser RA, Shu B, Soler G, Stjärne P, Stuck BA, Vodicka J, Welge-Luessen A (March 2017). "Position paper on olfactory dysfunction". Rhinol. Suppl. 54 (26): 1–30. doi:10.4193/Rhino16.248. PMID 29528615.
  9. ↑ Baig AM, Khaleeq A, Ali U, Syeda H (April 2020). "Evidence of the COVID-19 Virus Targeting the CNS: Tissue Distribution, Host-Virus Interaction, and Proposed Neurotropic Mechanisms". ACS Chem Neurosci. 11 (7): 995–998. doi:10.1021/acschemneuro.0c00122. PMC 7094171 Check |pmc= value (help). PMID 32167747 Check |pmid= value (help).
  10. ↑ Rockx B, Kuiken T, Herfst S, Bestebroer T, Lamers MM, Oude Munnink BB, de Meulder D, van Amerongen G, van den Brand J, Okba N, Schipper D, van Run P, Leijten L, Sikkema R, Verschoor E, Verstrepen B, Bogers W, Langermans J, Drosten C, Fentener van Vlissingen M, Fouchier R, de Swart R, Koopmans M, Haagmans BL (May 2020). "Comparative pathogenesis of COVID-19, MERS, and SARS in a nonhuman primate model". Science. 368 (6494): 1012–1015. doi:10.1126/science.abb7314. PMC 7164679 Check |pmc= value (help). PMID 32303590 Check |pmid= value (help). Vancouver style error: initials (help)
  11. ↑ Zou L, Ruan F, Huang M, Liang L, Huang H, Hong Z, Yu J, Kang M, Song Y, Xia J, Guo Q, Song T, He J, Yen HL, Peiris M, Wu J (March 2020). "SARS-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients". N. Engl. J. Med. 382 (12): 1177–1179. doi:10.1056/NEJMc2001737. PMC 7121626 Check |pmc= value (help). PMID 32074444 Check |pmid= value (help).
  12. ↑ 12.0 12.1 12.2 Dubé M, Le Coupanec A, Wong A, Rini JM, Desforges M, Talbot PJ (September 2018). "Axonal Transport Enables Neuron-to-Neuron Propagation of Human Coronavirus OC43". J. Virol. 92 (17). doi:10.1128/JVI.00404-18. PMC 6096804. PMID 29925652. Vancouver style error: initials (help)
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  15. ↑ Yao, Hangping; Lu, Xiangyun; Chen, Qiong; Xu, Kaijin; Chen, Yu; Cheng, Linfang; Liu, Fumin; Wu, Zhigang; Wu, Haibo; Jin, Changzhong; Zheng, Min; Wu, Nanping; Jiang, Chao; Li, Lanjuan (2020). doi:10.1101/2020.04.14.20060160. Missing or empty |title= (help)
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  17. ↑ Forster, Peter; Forster, Lucy; Renfrew, Colin; Forster, Michael (2020). "Phylogenetic network analysis of SARS-CoV-2 genomes". Proceedings of the National Academy of Sciences. 117 (17): 9241–9243. doi:10.1073/pnas.2004999117. ISSN 0027-8424.
  18. ↑ 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.
  19. ↑ 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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  22. ↑ 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)
  23. ↑ 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).
  24. ↑ 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)
  25. ↑ 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).
  26. ↑ 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).
  27. ↑ 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)
  28. ↑ 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).
  29. ↑ 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.
  30. ↑ 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.
  31. ↑ 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.
  32. ↑ 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.
  33. ↑ 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.
  34. ↑ 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.
  35. ↑ 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.
  36. ↑ 36.0 36.1 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.
  37. ↑ 37.0 37.1 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.
  38. ↑ 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)
  39. ↑ 39.0 39.1 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)
  40. ↑ "www.entuk.org" (PDF).
  41. ↑ 41.0 41.1 "AAO-HNSF 2020 Annual Meeting & OTO Experience | American Academy of Otolaryngology-Head and Neck Surgery".
  42. ↑ 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.
  43. ↑ 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.
  44. ↑ 44.0 44.1 44.2 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).
  45. ↑ 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).
  46. ↑ 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.
  47. ↑ 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.
  48. ↑ 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.
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  50. ↑ "Neue Corona-Symptome entdeckt: Virologe Hendrik Streeck zum Virus".
  51. ↑ 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).
  52. ↑ 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.
  53. ↑ 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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  56. ↑ 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.
  57. ↑ 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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