Distorted chemosensory perception and female sex associate with persistent smell and/or taste loss in people with SARS-CoV-2 antibodies: A community based cohort study investigating clinical course and resolution of acute smell and/or taste loss in people with and without SARS-CoV-2 antibodies in London, UK

Abstract Background:Loss of smell and/or taste are cardinal symptoms of COVID-19. ‘Long-COVID’, persistence of symptoms, affects around one fifth of people. However, data regarding the clinical resolution of loss of smell and/or taste are lacking. We assessed COVID-19 symptoms in a community cohort in London 4-6 weeks after they initially reported acute loss of their sense of smell and/or taste, 78% of whom had SARS-CoV-2 IgG/IgM antibodies. In addition, to assess whether self-reported change in sense of smell was reliable, we compared subjective and objective smell assessments in a subset of participants. Methods:467 participants with acute loss of smell and/or taste who had undergone SARS-CoV-2 IgG/IgM antibody testing 4-6 weeks earlier completed a follow-up questionnaire about resolution of their symptoms. A subsample of 50 participants completed an objective olfactory test and results were compared to subjective smell evaluations.Results:People with SARS-CoV-2 antibodies with an acute loss of sense of smell and taste were significantly less likely to recover their sense of smell/taste than people who were seronegative (smell recovery: 57.7% vs. 72.1% , p=0.027. taste recovery 66.2% vs. 80.3%, p=0.017). In SARS-CoV-2 positive participants, a higher percentage of male participants reported full resolution of smell loss (72.8% vs. 51.4%; p<0.001) compared to female participants, who were almost 2.5-times more likely to have ongoing smell loss after 4-6 weeks (OR 2.46, 95%CI 1.47-4.13, p=0.001). Female participants with SARS-CoV-2 antibodies and unresolved smell loss and unresolved taste loss were significantly older (>40 years) than those who reported full resolution. Participants who experienced parosmia reported lower smell recovery rates and participants with distorted taste perception lower taste recovery rates. Parosmia had a significant association to unresolved smell loss (OR 2.47, 95%CI 1.54-4.00, p<0.001). Conclusion:Although smell and/or taste loss are often transient manifestations of COVID-19, 42% of participants had ongoing loss of smell, 34% loss of taste and 36% loss of smell and taste at 4-6 weeks follow-up, which constitute symptoms of ‘long-COVID’. Females (particularly >40 years) and people with a distorted perception of their sense of smell/taste are likely to benefit from prioritised early therapeutic interventions. Trials registration:ClinicalTrials.gov NCT04377815

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Distorted chemosensory perception and female sex associate with persistent smell and/or taste loss in people with SARS-CoV-2 antibodies: a community based cohort study investigating clinical course and resolution of acute smell and/or taste loss in people with and without SARS-CoV-2 antibodies in London, UK

BMC Infectious Diseases ◽

10.1186/s12879-021-05927-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Janine Makaronidis ◽

Chloe Firman ◽

Cormac G. Magee ◽

Jessica Mok ◽

Nyaladzi Balogun ◽

...

Keyword(s):

Taste Perception ◽

Therapeutic Interventions ◽

Antibody Testing ◽

Recovery Rates ◽

Sense Of Smell ◽

Link Type ◽

Igm Antibody ◽

Full Resolution ◽

Smell Loss

Abstract Background Loss of smell and/or taste are cardinal symptoms of COVID-19. ‘Long-COVID’, persistence of symptoms, affects around one fifth of people. However, data regarding the clinical resolution of loss of smell and/or taste are lacking. In this study we assess smell and taste loss resolution at 4–6 week follow-up, aim to identify risk factors for persistent smell loss and describe smell loss as a feature of long-COVID in a community cohort in London with known SARS-CoV-2 IgG/IgM antibody status. We also compare subjective and objective smell assessments in a subset of participants. Methods Four hundred sixty-seven participants with acute loss of smell and/or taste who had undergone SARS-CoV-2 IgG/IgM antibody testing 4–6 weeks earlier completed a follow-up questionnaire about resolution of their symptoms. A subsample of 50 participants completed an objective olfactory test and results were compared to subjective smell evaluations. Results People with SARS-CoV-2 antibodies with an acute loss of sense of smell and taste were significantly less likely to recover their sense of smell/taste than people who were seronegative (smell recovery: 57.7% vs. 72.1%, p = 0.027. taste recovery 66.2% vs. 80.3%, p = 0.017). In SARS-CoV-2 positive participants, a higher percentage of male participants reported full resolution of smell loss (72.8% vs. 51.4%; p < 0.001) compared to female participants, who were almost 2.5-times more likely to have ongoing smell loss after 4–6 weeks (OR 2.46, 95%CI 1.47–4.13, p = 0.001). Female participants with SARS-CoV-2 antibodies and unresolved smell loss and unresolved taste loss were significantly older (> 40 years) than those who reported full resolution. Participants who experienced parosmia reported lower smell recovery rates and participants with distorted taste perception lower taste recovery rates. Parosmia had a significant association to unresolved smell loss (OR 2.47, 95%CI 1.54–4.00, p < 0.001). Conclusion Although smell and/or taste loss are often transient manifestations of COVID-19, 42% of participants had ongoing loss of smell, 34% loss of taste and 36% loss of smell and taste at 4–6 weeks follow-up, which constitute symptoms of ‘long-COVID’. Females (particularly > 40 years) and people with a distorted perception of their sense of smell/taste are likely to benefit from prioritised early therapeutic interventions. Trials registration ClinicalTrials.govNCT04377815 Date of registration: 23/04/2020.

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Six-month psychophysical evaluation of olfactory dysfunction in patients with COVID-19

Chemical Senses ◽

10.1093/chemse/bjab006 ◽

2021 ◽

Author(s):

Paolo Boscolo-Rizzo ◽

Anna Menegaldo ◽

Cristoforo Fabbris ◽

Giacomo Spinato ◽

Daniele Borsetto ◽

...

Keyword(s):

Olfactory Dysfunction ◽

University Of Pennsylvania ◽

Sense Of Smell ◽

Olfactory Test ◽

Culturally Adapted ◽

Psychophysical Evaluation ◽

Normal Sense ◽

Smell Identification

Abstract This study prospectively assessed the six-month prevalence of self-reported and psychophysically measured olfactory dysfunction in subjects with mild-to-moderate COVID-19. Self-reported smell or taste impairment was prospectively evaluated by SNOT-22 at diagnosis, 4-week, 8-week, and 6-month. At 6 months from the diagnosis, psychophysical evaluation of olfactory function was also performed using the 34-item culturally adapted University of Pennsylvania Smell Identification Test (CA-UPSIT). 145 completed both the 6-month subjective and psychophysical olfactory evaluation. According to CA-UPSIT, 87 subjects (60.0%) exhibited some smell dysfunction, with 10 patients being anosmic (6.9%) and 7 being severely microsmic (4.8%). At the time CA-UPSIT was administered, a weak correlation was observed between the self-reported alteration of sense of smell or taste and olfactory test scores (Spearman’s r=-0.26). Among 112 patients who self-reported normal sense of smell at last follow-up, CA-UPSIT revealed normal smell in 46 (41.1%), mild microsmia in 46 (41.1%), moderate microsmia in 11 (9.8%), severe microsmia in 3 (2.3%), and anosmia in 6 (5.4%) patients; however, of those patients self-reporting normal smell but who were found to have hypofunction on testing, 62 out of 66 had self-reported reduction in sense of smell or taste at an earlier time point. Despite most patients report a subjectively normal sense of smell, we observed a high percentage of persistent smell dysfunction at 6 months from the diagnosis of SARS-CoV-2 infection, with 11.7% of patients being anosmic or severely microsmic. These data highlight a significant long-term rate of smell alteration in patients with previous SARS-COV-2 infection.

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High prevalence of long-term psychophysical olfactory dysfunction in patients with COVID-19

10.1101/2021.01.07.21249406 ◽

2021 ◽

Author(s):

Paolo Boscolo-Rizzo ◽

Anna Menegaldo ◽

Cristoforo Fabbris ◽

Giacomo Spinato ◽

Daniele Borsetto ◽

...

Keyword(s):

Olfactory Dysfunction ◽

University Of Pennsylvania ◽

Sense Of Smell ◽

Olfactory Test ◽

Culturally Adapted ◽

High Prevalence ◽

Psychophysical Evaluation ◽

Normal Sense

This study prospectively assessed the long-term prevalence of self-reported and psychophysically measured olfactory dysfunction in subjects with mild-to-moderate COVID-19. Self-reported smell or taste impairment was prospectively evaluated by SNOT-22 at diagnosis, 4-week, 8-week, and 6-month. At 6 months from the diagnosis, psychophysical evaluation of olfactory function was also performed using the 34-item culturally adapted University of Pennsylvania Smell Identification Test (CA-UPSIT). 145 completed both the 6-month subjective and psychophysical olfactory evaluation. According to CA-UPSIT, 87 subjects (60.0%) exhibited some smell dysfunction, with 54 (37.2) being mildly microsmic, 16 (11.0%) moderately microsmic, 7 (4.8%) severely microsmic, and 10 patients (6.9%) being anosmic. At the time CA-UPSIT was administered, a weak correlation was observed between the self-reported alteration of sense of smell or taste and olfactory test scores (Spearman r=-0.26). Among 112 patients who self-reported normal sense of smell at last follow-up, CA-UPSIT revealed normal smell in 46 (41.1%), mild microsmia in 46 (41.1%), moderate microsmia in 11 (9.8%), severe microsmia in 3 (2.3%), and anosmia in 6 (5.4%) patients; however, of those patients self-reporting normal smell but who were found to have hypofunction on testing, 62 out of 66 had self-reported reduction in sense of smell or taste at an earlier time point. Despite most patients report a subjectively normal sense of smell, we observed a high percentage of persistent smell dysfunction at 6 months from the diagnosis of SARS-CoV-2 infection, with 11.7% of patients being anosmic or severely microsmic. These data highlight a significant long-term rate of smell alteration in patients with previous SARS-CoV-2 infection.

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Effects of COVID-19 on Sense of Smell: Human Factors/Ergonomics Considerations

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/0018720821990162 ◽

2021 ◽

pp. 001872082199016

Author(s):

E. Leslie Cameron ◽

Per Møller ◽

Keith S. Karn

Keyword(s):

Human Factors ◽

Olfactory Dysfunction ◽

System Communication ◽

Human System ◽

Sense Of Smell ◽

Primary Means ◽

Human Sense ◽

Smell Loss

Objective We review the effects of COVID-19 on the human sense of smell (olfaction) and discuss implications for human-system interactions. We emphasize how critical smell is and how the widespread loss of smell due to COVID-19 will impact human-system interaction. Background COVID-19 reduces the sense of smell in people who contract the disease. Thus far, olfaction has received relatively little attention from human factors/ergonomics professionals. While smell is not a primary means of human-system communication, humans rely on smell in many important ways related to both quality of life and safety. Method We briefly review and synthesize the rapidly expanding literature through September 2020 on the topic of smell loss caused by COVID-19. We interpret findings in terms of their relevance to human factors/ergonomics researchers and practitioners. Results Since March 2020 dozens of articles have been published that report smell loss in COVID-19 patients. The prevalence and duration of COVID-19-related smell loss is still under investigation, but the available data suggest that it may leave many people with long-term deficits and distortions in sense of smell. Conclusion We suggest that the human factors/ergonomics community could become more aware of the importance of the sense of smell and focus on accommodating the increasing number of people with reduced olfactory performance. Application We present examples of how olfaction can augment human-system communication and how human factors/ergonomics professionals might accommodate people with olfactory dysfunction. While seemingly at odds, both of these goals can be achieved.

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AB0702 PITFALLS IN THE DIAGNOSIS OF COVID-19 – EXPERIENCES FROM A RHEUMATOLOGY OUTPATIENT CLINIC

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2021-eular.3798 ◽

2021 ◽

Vol 80 (Suppl 1) ◽

pp. 1383.2-1383

Author(s):

S. G. Werner ◽

H. E. Langer ◽

P. Höhenrieder ◽

R. Chatelain

Keyword(s):

Outpatient Clinic ◽

Virus Disease ◽

Disease Onset ◽

Signs And Symptoms ◽

Contact Tracing ◽

Igg Antibodies ◽

Antibody Testing ◽

Antibody Titers ◽

Rheumatology Outpatient

Background:PCR (Polymerase Chain Reaction) is generally considered the gold standard for confirming the diagnosis in the early stages of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. However, in our rheumatology outpatient clinic we observed a significant discrepancy between clinical evidence of COVID-19 and PCR results.Objectives:Aim of this retrospective study was to analyze the significance of PCR and serologic tests in the diagnosis of COVID-19 (Corona Virus Disease 2019) in a cohort of patients with rheumatic diseases.Methods:Between March 2020 and January 2021, 35 patients with a history of established COVID-19 or typical signs and symptoms were identified on the occasion of a routine rheumatology follow-up examination in our institution. Previous diagnostic work-up in external facilities (results of PCR or antibody testing, imaging) was documented. Antibody ELISA-tests (IgG, IgA, IgM, Euroimmun) were performed in patients reporting typical signs and symptoms of COVID-19 in the past.Results:PCR diagnostics had been performed in 15/35 patients (43%), in 13/35 (39%) at the onset of the first symptoms, in 2 subjects only 2 months later. PCR was positive in 7/13 (54%) of those tested early, but negative in the two patients tested later. In 29/35 patients (83%) SARS-CoV-2-ELISA tests were performed on the occasion of the routine rheumatologic examination (interval between first symptoms and testing on average 98 days, median86, range 4-283 days). In two of the initially negative individuals the second PCR was positive. ELISA tests were positive in all patients. SARS-CoV-2 IgM antibodies were positive in only two patients (however 55 and 71 days after disease onset), n=8/29 (28%) IgG only, n=9/29 (31%) IgG and IgA, n=12/29 (41%) IgA only. In these subjects, IgG antibodies did not develop even in the further course. Antibody titers were in part very high, but in part also very low (only just above the normal value), so even low titers were diagnostic obviously. In all patients with negative PCR, ELISA was positive and retrospectively led to confirmation of the diagnosis. Only in 13/35 patients (37%) diagnosis had been made with the onset of the first symptoms or in the course of clinically manifest disease and had led to appropriate quarantine measures and contact tracing by the health authorities. In contrast, in the majority of patients (63%), the diagnosis of COVID-19 infection was only made retrospectively on the occasion of a routine rheumatologic follow-up. However, 5 of these 22 patients (23%) had quarantined themselves during the symptomatic phase. Titer histories were available from 12 patients. The titer became negative in 7 patients, after a mean of 188 days (median 202, min 51, max 296 days), and remained positive in 5 individuals (mean 190 days, median 191, min 122, max 260 days). The change of the titer was independent of disease severity or antirheumatic therapy.Conclusion:The results suggest that the importance of PCR in the diagnosis of COVID-19 may be overestimated. Therefore, antibody testing for SARS-CoV-2 should be performed in cases of clinical suspicion and negative PCR. In antibody diagnostics, special features were observed compared to other viruses, in particular, in some patients only low antibody titers or the absence of seroconversion with lack of development of IgG antibodies. Normalization of antibody titers in some patients supports the recommendation to vaccinate even after expired COVID-19 disease.Disclosure of Interests:None declared

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SARS-CoV-2/DENV co-infection: a series of cases from the Federal District, Midwestern Brazil

BMC Infectious Diseases ◽

10.1186/s12879-021-06456-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Heidi Luise Schulte ◽

José Diego Brito-Sousa ◽

Marcus Vinicius Guimarães Lacerda ◽

Luciana Ansaneli Naves ◽

Eliana Teles de Gois ◽

...

Keyword(s):

Clinical Signs ◽

Federal District ◽

Therapeutic Interventions ◽

Diagnostic Process ◽

The Novel ◽

Prevention Measures ◽

Laboratory Findings ◽

Novel Coronavirus ◽

The Impact

Abstract Background Since the novel coronavirus disease outbreak, over 179.7 million people have been infected by SARS-CoV-2 worldwide, including the population living in dengue-endemic regions, particularly Latin America and Southeast Asia, raising concern about the impact of possible co-infections. Methods Thirteen SARS-CoV-2/DENV co-infection cases reported in Midwestern Brazil between April and September of 2020 are described. Information was gathered from hospital medical records regarding the most relevant clinical and laboratory findings, diagnostic process, therapeutic interventions, together with clinician-assessed outcomes and follow-up. Results Of the 13 cases, seven patients presented Acute Undifferentiated Febrile Syndrome and six had pre-existing co-morbidities, such as diabetes, hypertension and hypopituitarism. Two patients were pregnant. The most common symptoms and clinical signs reported at first evaluation were myalgia, fever and dyspnea. In six cases, the initial diagnosis was dengue fever, which delayed the diagnosis of concomitant infections. The most frequently applied therapeutic interventions were antibiotics and analgesics. In total, four patients were hospitalized. None of them were transferred to the intensive care unit or died. Clinical improvement was verified in all patients after a maximum of 21 days. Conclusions The cases reported here highlight the challenges in differential diagnosis and the importance of considering concomitant infections, especially to improve clinical management and possible prevention measures. Failure to consider a SARS-CoV-2/DENV co-infection may impact both individual and community levels, especially in endemic areas.

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Acute bilateral foot drop with or without cauda equina syndrome—a case series

Acta Neurochirurgica ◽

10.1007/s00701-021-04735-0 ◽

2021 ◽

Vol 163 (4) ◽

pp. 1191-1198

Author(s):

Andreas K. Demetriades ◽

Marco Mancuso-Marcello ◽

Asfand Baig Mirza ◽

Joseph Frantzias ◽

David A. Bell ◽

...

Keyword(s):

Cauda Equina Syndrome ◽

Cauda Equina ◽

Case Series ◽

Foot Drop ◽

Spinal Disease ◽

Full Resolution ◽

Degenerative Spinal Disease ◽

The Mean ◽

The One

Abstract Introduction Isolated acute bilateral foot drop due to degenerative spine disease is an extremely rare neurosurgical presentation, whilst the literature is rich with accounts of chronic bilateral foot drop occurring as a sequela of systemic illnesses. We present, to our knowledge, the largest case series of acute bilateral foot drop, with trauma and relevant systemic illness excluded. Methods Data from three different centres had been collected at the time of historic treatment, and records were subsequently reviewed retrospectively, documenting the clinical presentation, radiological level of compression, timing of surgery, and degree of neurological recovery. Results Seven patients are presented. The mean age at presentation was 52.1 years (range 41–66). All patients but one were male. All had a painful radiculopathic presentation. Relevant discopathy was observed from L2/3 to L5/S1, the commonest level being L3/4. Five were treated within 24 h of presentation, and two within 48 h. Three had concomitant cauda equina syndrome; of these, the first two made a full motor recovery, one by 6 weeks follow-up and the second on the same-day post-op evaluation. Overall, five out of seven cases had full resolution of their ankle dorsiflexion pareses. One patient with 1/5 power has not improved. Another with 1/5 weakness improved to normal on the one side and to 3/5 on the other. Conclusion When bilateral foot drop occurs acutely, we encourage the consideration of degenerative spinal disease. Relevant discopathy was observed from L2/3 to L5/S1; aberrant innervation may be at play. Cauda equina syndrome is not necessarily associated with acute bilateral foot drop. The prognosis seems to be pretty good with respect to recovery of the foot drop, especially if partial at presentation and if treated within 48 h.

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No Evidence That Hormonal Contraceptives Affect Chemosensory Perception

i-Perception ◽

10.1177/2041669520983339 ◽

2021 ◽

Vol 12 (1) ◽

pp. 204166952098333

Author(s):

Martin Schaefer ◽

Behzad Iravani ◽

Artin Arshamian ◽

Johan N. Lundström

Keyword(s):

Potential Effect ◽

Bayes Factors ◽

Taste Perception ◽

Hormonal Contraceptives ◽

Trigeminal System ◽

Odor Perception ◽

Chemosensory Perception ◽

Long Time ◽

Taste Detection ◽

Taste Thresholds

The use of oral contraceptives (OC) in the form of a hormonal pill has been widespread for decades. Despite its popularity and long-time use, there is still much ambiguity and anecdotal reports about a range of potential side effects. Here, we addressed the potential effect of OC use on chemosensory perception. Previous research has almost exclusively focused on olfaction, but we expanded this to the trigeminal system and the sense of taste. We used Bayesian statistics to compare the olfactory, trigeminal, and taste detection abilities between a group of 34 normal cycling women and a group of 26 women using OC. Our results indicated that odor, trigeminal, and taste thresholds were not affected by the use of OC. Moreover, neither odor perception, nor taste perception was affected; all with Bayes factors consistently favoring the null hypothesis. The only exception to these results was odor identification where Bayes factors indicated inconclusive evidence. We conclude that effects of OC use on chemosensory perception are unlikely, and if present, likely are of no to little behavioral relevance.

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Adverse reactions to oxacillin in hospitalized children: a prospective study

Revista Brasileira de Saúde Materno Infantil ◽

10.1590/s1519-38292007000100007 ◽

2007 ◽

Vol 7 (1) ◽

pp. 55-61 ◽

Cited By ~ 1

Author(s):

Mariana de Oliveira Brizeno de Souza ◽

Maria da Conceição Castro de Araújo ◽

Raquel Araújo de Santiago ◽

Helena Lutéscia Luna Coelho ◽

Marta Maria de França Fonteles

Keyword(s):

Exposure Time ◽

Treatment Duration ◽

Adverse Reactions ◽

Therapeutic Interventions ◽

Hospitalized Children ◽

Significant Relation ◽

Moderate Severity ◽

A Prospective Study ◽

Established Treatment

OBJECTIVES: follow-up of children exposed to oxacillin during hospitalization focusing on adverse reactions. METHODS: patients were selected from the pediatric wards of two hospitals in Fortaleza (Hospital Universitário Walter Cantídio-HUWC and Hospital Infantil Albert Sabin-HIAS) from the first oxacillin prescription with a prospective cohort study between October, 2000 and July, 2001 (HUWC) and July/2001 and March, 2002 (HIAS). Patients' follow-up was performed by daily visits to the wards and medical charts and prescription analysis. Suspected oxacillininduced adverse reactions (OxAR cases) were notified and classified according to causality and severity. Related statistic tests were completed. RESULTS: of the 130 patients exposed to oxacillin, 27 had OxAR (20.8%). Fever was the most frequent reaction (50%) followed by rash (35.7%). The majority of reactions were considered Probable, for oxacillin was the only medication involved and 92.6% of the cases had Moderate severity with the need of therapeutic interventions caused by OxAR. A significant relation between oxacillin exposure time and OxAR was determined as well as hospitalization time and the appearance of adverse reactions. Exposure time over 14 days to oxacillin was established as a risk factor for OxAR (relative risk = 5.49). CONCLUSIONS: careful administration of oxacillin in children is recommended with established treatment duration. Empiric and prolonged use must be avoided.

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Symptom reporting in over 1 million people: community detection of COVID-19

10.1101/2021.02.10.21251480 ◽

2021 ◽

Author(s):

Joshua Elliott ◽

Matthew Whitaker ◽

Barbara Bodinier ◽

Steven Riley ◽

Helen Ward ◽

...

Keyword(s):

Rapid Identification ◽

Current Approach ◽

Appetite Loss ◽

Sense Of Smell ◽

Symptom Profiles ◽

New Variant ◽

Selection Approach ◽

Community Transmission ◽

Polymerase Chain ◽

Smell Loss

SummaryControl of the SARS-CoV-2 epidemic requires rapid identification and isolation of infected individuals and their contacts. Community testing in England (Pillar 2) by polymerase chain reaction (PCR) is reserved for those reporting at least one of four ‘classic’ COVID-19 symptoms (loss or change of sense of smell, loss or change of sense of taste, fever, new continuous cough).1 Detection of positive cases in the community might be improved by including additional symptoms and their combinations. We used data from the REal-time Assessment of Community Transmission-1 (REACT-1) study to investigate symptom profiles for PCR positivity at different ages. Among rounds 2–7 (June to December 2020), an age-stratified, variable selection approach stably selected chills (all ages), headache (5–17 years), appetite loss (18–54 and 55+ years) and muscle aches (18–54 years) as jointly and positively predictive of PCR positivity together with the classic four symptoms. Between round 7 (November to December 2020) and round 8 (January 2021) when new variant B.1.1.7 predominated, only loss or change of sense of smell (more predictive in round 7) and (borderline) new persistent cough (more predictive in round 8) differed between cases. At any level of PCR testing, triage based on the symptoms identified here would result in more cases detected than the current approach.

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