Objective evaluation of anosmia and ageusia in COVID-19 patients: Single-center experience on 72 cases

Symptomatology of COVID-19 from the otorhinolaryngology perspective: a survey of 223 SARS-CoV-2 RNA-positive patients

PURPOSE

To determine prevalence, severity, duration, and time from onset to diagnosis of general and Otorhinolaryngologic symptoms related to COVID-19 in whole disease spectrum: from mild to critical patients.

METHODS

All adult patients with positive SARS-CoV-2 RNA found in nasopharyngeal and oropharyngeal swabs between March 10 and April 21, 2020 were surveyed by the authors for new onset symptoms during disease course. Demographic features, general symptoms, and Otorhinolaryngological symptoms were evaluated and compared by disease severity.

RESULTS

Of 223 included patients, 18.4% had mild, 61.4%; moderate, 14.3%; severe, and 5.8%; critical disease. Median age was 51 (range 20-93), 113 (50.7%) were male and 110 (49.3%) were female. The most common general symptoms were fatigue, cough, and fever with respective frequencies of 71.3%, 54.3%, and 50.7%. The most common Otorhinolaryngologic symptoms were taste loss, smell loss, and sore throat with respective frequencies of 34.5%, 31.8%, and 26%. Fatigue, fever, and dyspnea were more common in severe-critical patients compared to mild-moderate patients (p = 0.029, p = 0.016, and p < 0.001, respectively). Only smell loss was more common in mild-moderate group (p = 0.003). Prevalence of other symptoms did not differ between groups. Symptom durations and onset time to diagnosis varied.

CONCLUSION

When compared to the previous studies, while general symptoms were less common, Otorhinolaryngologic symptoms were more common in our study population. Considering high infection risks, Otorhinolaryngologists should be aware of COVID-19 patients presenting with Otorhinolaryngologic complaints.

Oral Corticosteroid Relieves Post-COVID-19 Anosmia in a 35-Year-Old Patient

Coronavirus disease 2019 (COVID-19) is a highly infectious respiratory illness caused by SARS-CoV-2. Not much is yet known about this new viral disease. In our early encounter with the COVID-19, before the pandemic and during the early days of dealing with this novel viral disease in our country, we saw some cases of anosmia in patients infected by SARS-CoV-2. In many cases, this chemosensitive dysfunction persisted after the negativization of the nasopharyngeal swab. We report effective treatment of anosmia by oral corticosteroid therapy in a patient recovered from COVID-19.

Do olfactory and gustatory psychophysical scores have prognostic value in COVID-19 patients? A prospective study of 106 patients

Background

The lack of objective data makes it difficult to establish the prognostic value of chemosensitive disorders in coronavirus disease 2019 (COVID-19) patients. We aimed to prospectively monitor patients diagnosed with COVID-19 to see if the severity of olfactory and gustatory dysfunction associates with subsequent disease severity.

Methods

Multicentre prospective study that recruited 106 COVID-19 subjects at diagnosis. Chemosensitive functions were assessed with psychophysical tests within 4 days of clinical onset, at 10 and 20 days. Daily body temperature and oxygen saturation were recorded as markers of disease severity alongside need for hospitalisation. The correlation between olfactory and gustatory scores and disease severity was assessed with linear regression analysis.

Results

At T0, 71 patients (67%) presented with olfactory dysfunction while gustatory impairment was detected in 76 cases (65.6%). Chemosensitive disorders gradually improved over the observation period. No significant correlations were found between T0 chemosensitive scores and final disease severity. The correlation between olfactory scores and fever proved significant at T2 (p = 0.05), while the relationship with gustatory scores was significant at T1 (p = 0.01) and T2 (p <  0.001), however neither was clinically relevant. The correlation between chemosensitive scores and oxygen saturation was significant only for taste at T2 (p <  0.001). Logistic regression analysis found significant correlations between olfactory impairment severity and need for hospitalization at T2 (OR 3.750, p = 0.005).

Conclusions

Initial objective olfactory and gustatory scores do not seem to have a significant prognostic value in predicting the severity of the COVID-19 course; however, persistence of olfactory dysfunction at 20 days, associated with a more severe course. Unfortunately, olfactory and gustatory dysfunction do not seem to hold prognostic value at the time of initial diagnosis.

Psychophysical evaluation of chemosensory functions 5 weeks after olfactory loss due to COVID-19: a prospective cohort study on 72 patients

Purpose

To evaluate the evolution of chemosensation via extended psychophysical testing in patients who suffered from sudden chemosensory loss due to coronavirus disease 2019 (COVID-19). Additionally, this study sought to determine whether odor threshold testing provided additional information on olfactory loss due to COVID-19 compared to the more common odor identification testing.

Methods

Prospective cohort study of patients with sudden chemosensory loss since February 2020 and confirmed COVID-19 infection via RT-PCR or serology testing. Olfactory function was tested extensively using the “Sniffin Sticks” test battery. In addition, we screened gustatory perception and nasal cooling sensations using psychophysical tests.

Results

Seventy-two patients completed the study. After a mean of 37 days, 37% of patients showed olfactory dysfunction, 7% were dysgeusic, and 48% showed signs of low sensitivity for cooling sensation. A longer duration of anosmia before smell improvement was correlated with lower olfactory function at 5 weeks. Odor threshold detection was more affected by COVID-19 compared to odor identification.

Conclusion

Five weeks after developing sudden chemosensory loss due to COVID-19, a high proportion of patients were dysosmic and showed signs of low nasal cooling sensitivity, whereas most of them had normal taste function. SARS-CoV-2 affected mainly odor thresholds, possibly suggesting that the major cause of loss of smell lies at the level of the olfactory neuroepithelium, rather than in the central nervous system.

A structural equation model to examine the clinical features of mild-to-moderate COVID-19: A multicenter Italian study

The purpose of this study was to evaluate the clinical features of mild-to-moderate coronavirus disease 2019 (COVID-19) in a sample of Italian patients and to investigate the occurrence of smell and taste disorders. Infected individuals with suspected (clinical diagnosis) or laboratory-confirmed COVID-19 infection were recruited. Patients completed a survey-based questionnaire with the aim of assessing their epidemiological and clinical characteristics, general otorhinolaryngological symptoms, and smell and taste disorders. A total of 294 patients with mild-to-moderate COVID-19 completed the survey (147 females). The most prevalent general symptoms included fever, myalgia, cough, and headache. A total of 70.4% and 59.2% of patients reported smell and taste disorders, respectively. A significant association between the two above-mentioned disorders was found (rs: 0.412; P < .001). Smell disorders occurred before the other symptoms in 11.6% of patients and was not significantly associated with nasal obstruction or rhinorrhea. Interestingly, our statistical analysis did not show any significant difference, either for general symptoms or otorhinolaryngological features, between the clinical diagnosis group and the laboratory-confirmed diagnosis (polymerase chain reaction) group. The structural equation model confirmed significant standardized paths (P < .05) between general symptoms, comorbidities, and general otorhinolaryngological complaints in the absence of a significant correlation between these elements and smell and taste alterations. The prevalence of smell and taste disorders in mild-to-moderate Italian COVID-19 patients is significant both in suspected and laboratory-confirmed cases and reveals a strong correlation between these clinical signs regardless of the presence of general or otorhinolaryngological symptoms, such as nasal obstruction or rhinorrhea.

SARS-CoV-2 and Nervous System - Neurological Manifestations in Patients With COVID-19: A Systematic Review

Coronavirus (CoV) is a virus infectious disease with a considerable spectrum of clinical presentations. Symptoms ranged from asymptomatic infection to severe pneumonia that may lead to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and several clinical complications. Neurologic symptoms related to CoV have been described recently in the literature. The relationship between SARS-CoV-2 and the central nervous system (CNS) is still not clear. This review aimed to reveal the current knowledge regarding CNS manifestation in SARS-CoV-2. A systematic literature review was carried out to identify the particularities of coronavirus disease 2019 (COVID-19) in patients with CNS involvement, using the PubMed database between January 1, 2020 and April 30, 2020. Conference papers, reviews, published letters, editorials, studies in pregnant women and children, and studies only reporting on a specific factor were excluded. An initial search included as many as 83 articles. Out of the 83 screened articles, 32 were selected for full-text review. Sixteen studies were excluded because they did not analyze nervous system involvement in SARS-CoV-2 infection. Thus, 16 papers were included in this review. There were three retrospective studies and 13 case reports/series of cases. Data from the current literature reveal that patients who suffer from a severe illness have more CNS involvement, neurological symptoms (i.e., dizziness, headache) and an association with strokes. The severe patients had higher D-dimer and C-reactive protein levels than non-severe patients and presented multiple organ involvement, such as serious liver, kidney and muscle damage.

Loss of smell in COVID-19 patients: a critical review with emphasis on the use of olfactory tests

Since December 2019, an outbreak of a newly isolated coronavirus (SARS-CoV-2) appeared in Wuhan, China, and then spread worldwide. Recently, it has emerged that a number of patients may present with sudden hyposmia, sometimes without other symptoms of the disease. We performed a critical review on the methods used to date to investigate the olfactory function in COVID-19 patients in order to establish which should be considered the most appropriate to use during this pandemic. Literature analysis showed that the diagnosis of hyposmia in COVID-19 patients was mainly made through subjective symptomatology collected by questionnaires and/or interview. Psychophysical tests were carried out in a few studies showing significant discrepancies between the self-reported sense of smell and test results. To date the methods used by authors to investigate smell impairment in COVID-19 patients have been very heterogeneous and predominantly based on self-reported questionnaires leading to confusing and inconclusive results. We suggest that simple validated self-administered psychophysical olfactory tests could be a valuable instrument to investigate isolated/quarantined or hospitalised COVID-19 patients referring smell impairment in order to confirm olfactory dysfunction.

ENT manifestation in COVID-19 patients

OBJECTIVE

to detect, analyze and discuss the different ear nose throat (ENT) manifestations those were reported in COVID19 positive patients in the reviewed and published literatures.

METHODS

We performed a search in the PubMed databases, Web of Science, LILACS, MEDLINE, SciELO, and Cochrane Library using the keywords; COVID-19, Novel coronavirus, corona, 2019-nCoV, SARS-CoV-2, ENT, ear, nose, throat, otorhinolaryngology, ORL, pharynx, ORL, smell, larynx, different ENT related symptoms. We reviewed published and peer reviewed studies that reported the ENT manifestations in COVID-19 laboratory-confirmed positive patients.

RESULTS

within the included 1773 COVID-19 laboratory-confirmed positive patients, the most common ENT manifestations of COVID-19 were sore throat (11.3%) and headache (10.7%). While the other reported ENT manifestations were pharyngeal erythema (5.3%), nasal congestion (4.1%), runny nose or rhinorrhea (2.1%), upper respiratory tract infection (URTI) (1.9%), and tonsil enlargement (1.3%).

CONCLUSION

ENT manifestations for COVID-19 are not common as fever and cough. But, a universal questionnaire using well-defined COVID-19 manifestations is needed to make the COVID-19 data precisely defined, complete and homogenous.

[Smell disorders at COVID-19 - the current level of knowledge]

Early reports of SARS-CoV-2 infections only rarely mentioned smell and taste disorders. Several studies, particularly from Europe and the USA, have now confirmed these symptoms as an early key feature of COVID-19. About 70 % of patients seem to experience a reduction of smell and taste in the course of the disease, with most of the studies published to date based on questionnaires and anamnestic data. Validated smell tests have so far only been used in a few studies. A distinction between taste and taste disorders, i. e. a distinction between retronasal aroma taste and the olfactory system from the dysfunction of taste capsules and the further cranial nerves, was mostly not made in the studies available to date. Some reports associate olfactory disorders with a milder clinical course. At the same time, the olfactory system via the olfactory bulb represents an entry point into the central nervous system, and an olfactory disorder could be a predisposing factor for central neurological symptoms. The clinical significance of smell and taste disorders in COVID-19 patients is currently still unclear. Further open questions concern the exact prevalence and the prognosis, so that overall higher quality studies with validated smell tests and larger numbers of patients are required.

Diagnosing COVID-19 in the Emergency Department: A Scoping Review of Clinical Examinations, Laboratory Tests, Imaging Accuracy, and Biases

OBJECTIVE

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged as a global pandemic in early 2020 with rapidly evolving approaches to diagnosing the clinical illness called coronavirus disease (COVID-19). The primary objective of this scoping review is to synthesize current research of the diagnostic accuracy of history, physical examination, routine laboratory tests, real-time reverse transcription-polymerase chain reaction (rRT-PCR), immunology tests, and computed tomography (CT) for the emergency department (ED) diagnosis of COVID-19. Secondary objectives included a synopsis of diagnostic biases likely with current COVID-19 research as well as corresponding implications of false-negative and false-positive results for clinicians and investigators.

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Scoping Review (PRISMA-ScR)-adherent synthesis of COVID-19 diagnostic accuracy through May 5, 2020, was conducted. The search strategy was designed by a medical librarian and included studies indexed by PubMed and Embase since January 2020.

RESULTS

A total of 1,907 citations were screened for relevance. Patients without COVID-19 are rarely reported, so specificity and likelihood ratios were generally unavailable. Fever is the most common finding, while hyposmia and hypogeusia appear useful to rule in COVID-19. Cough is not consistently present. Lymphopenia is the mostly commonly reported laboratory abnormality and occurs in over 50% of COVID-19 patients. rRT-PCR is currently considered the COVID-19 criterion standard for most diagnostic studies, but a single test sensitivity ranges from 60% to 78%. Multiple reasons for false-negatives rRT-PCR exist, including sample site tested and disease stage during which sample was obtained. CT may increase COVID-19 sensitivity in conjunction with rRT-PCR, but guidelines for imaging patients most likely to benefit are emerging. IgM and IgG serology levels are undetectable in the first week of COVID-19, but sensitivity (range = 82% to 100%) and specificity (range = 87% to 100%) are promising. Whether detectable COVID-19 antibodies correspond to immunity remains unanswered. Current studies do not adhere to accepted diagnostic accuracy reporting standards and likely report significantly biased results if the same tests were to be applied to general ED populations with suspected COVID-19.

CONCLUSIONS

With the exception of fever and disorders of smell/taste, history and physical examination findings are unhelpful to distinguish COVID-19 from other infectious conditions that mimic SARS-CoV-2 like influenza. Routine laboratory tests are also nondiagnostic, although lymphopenia is a common finding and other abnormalities may predict severe disease. Although rRT-PCR is the current criterion standard, more inclusive consensus-based criteria will likely emerge because of the high false-negative rate of PCR tests. The role of serology and CT in ED assessments remains undefined.

Smell and Taste Dysfunction in Patients With COVID-19: A Systematic Review and Meta-analysis

OBJECTIVE

To estimate the prevalence of olfactory and gustatory dysfunctions (OGDs) among patients infected with novel coronavirus disease 2019 (COVID-19).

METHODS

A systematic review was conducted by searching MEDLINE, EMBASE, and the preprint server MedRxiv from their inception until May 11, 2020, using the terms anosmia or hyposmia or dysosmia or olfactory dysfunction or olfaction disorder or smell dysfunction or ageusia or hypogeusia or dysgeusia or taste dysfunction or gustatory dysfunction or neurological and COVID-19 or 2019 novel coronavirus or 2019-nCoV or SARS-CoV-2. The references of included studies were also manually screened. Only studies involving patients with diagnostic-confirmed COVID-19 infection were included. Random-effects meta-analysis was performed.

RESULTS

Twenty-four studies with data from 8438 patients with test-confirmed COVID-19 infection from 13 countries were included. The pooled proportions of patients presenting with olfactory dysfunction and gustatory dysfunction were 41.0% (95% CI, 28.5% to 53.9%) and 38.2% (95% CI, 24.0% to 53.6%), respectively. Increasing mean age correlated with lower prevalence of olfactory (coefficient = -0.076; P=.02) and gustatory (coefficient = -0.073; P=.03) dysfunctions. There was a higher prevalence of olfactory dysfunctions with the use of objective measurements compared with self-reports (coefficient = 2.33; P=.01). No significant moderation of the prevalence of OGDs by sex was observed.

CONCLUSION

There is a high prevalence of OGDs among patients infected with COVID-19. Routine screening for these conditions could contribute to improved case detection in the ongoing COVID-19 pandemic. However, to better inform population screening measures, further studies are needed to establish causality.

Smell and taste recovery in coronavirus disease 2019 patients: a 60-day objective and prospective study

BACKGROUND

The long-term recovery rate of chemosensitive functions in coronavirus disease 2019 patients has not yet been determined.

METHOD

A multicentre prospective study on 138 coronavirus disease 2019 patients was conducted. Olfactory and gustatory functions were prospectively evaluated for 60 days.

RESULTS

Within the first 4 days of coronavirus disease 2019, 84.8 per cent of patients had chemosensitive dysfunction that gradually improved over the observation period. The most significant increase in chemosensitive scores occurred in the first 10 days for taste and between 10 and 20 days for smell. At the end of the observation period (60 days after symptom onset), 7.2 per cent of the patients still had severe dysfunctions. The risk of developing a long-lasting disorder becomes significant at 10 days for taste (odds ratio = 40.2, 95 per cent confidence interval = 2.204-733.2, p = 0.013) and 20 days for smell (odds ratio = 58.5, 95 per cent confidence interval = 3.278-1043.5, p = 0.005).

CONCLUSION

Chemosensitive disturbances persisted in 7.2 per cent of patients 60 days after clinical onset. Specific therapies should be initiated in patients with severe olfactory and gustatory disturbances 20 days after disease onset.

Neuropathogenesis of SARS-CoV-2 infection

The COVID-19 pandemic caused by the SARS-CoV-2 has recently emerged as a serious jolt to human life and economy. Initial knowledge established pulmonary complications as the chief symptom, however, the neurological aspect of the disease is also becoming increasingly evident. Emerging reports of encephalopathies and similar ailments with the detection of the virus in the CSF has elicited an urgent need for investigating the possibility of neuroinvasiveness of the virus, which cannot be ruled out given the expression of low levels of ACE2 receptors in the brain. Sensory impairments of the olfactory and gustatory systems have also been reported in a large proportion of the cases, indicating the involvement of the peripheral nervous system. Hence, the possibility of neurological damage caused by the virus demands immediate attention and investigation of the mechanisms involved, so as to customize the treatment of patients presenting with neurological complications.

Remote psychophysical evaluation of olfactory and gustatory functions in early-stage coronavirus disease 2019 patients: the Bologna experience of 300 cases

BACKGROUND

An objective evaluation of coronavirus disease 2019 in the first days of infection is almost impossible, as affected individuals are generally in home quarantine, and there is limited accessibility for the operator who should perform the test. To overcome this limitation, a recently validated psychophysical self-administered test was used, which can be performed remotely in the assessment of early-stage coronavirus disease 2019 patients.

METHODS

Olfactory and gustatory functions were objectively assessed in 300 patients in the first 7 days from coronavirus disease 2019 symptom onset.

RESULTS

Seventy per cent of the patients presented olfactory and/or gustatory disorders. The dysfunctions detected were mainly complete anosmia (47 per cent) or ageusia (38 per cent). A significant correlation was found between taste dysfunction and female gender (odds ratio = 1.936, p = 0.014) and fever (odds ratio = 2.132, p = 0.003).

CONCLUSION

The psychophysical evaluation protocol proposed is an effective tool for the fast and objective evaluation of patients in the early stages of coronavirus disease 2019. Chemosensitive disorders have been confirmed to be frequent and early symptoms of the coronavirus infection, and, in a significant number of cases, they are the first or only manifestation of coronavirus disease 2019.

COVID-19 and the Chemical Senses: Supporting Players Take Center Stage

The main neurological manifestation of COVID-19 is loss of smell or taste. The high incidence of smell loss without significant rhinorrhea or nasal congestion suggests that SARS-CoV-2 targets the chemical senses through mechanisms distinct from those used by endemic coronaviruses or other common cold-causing agents. Here we review recently developed hypotheses about how SARS-CoV-2 might alter the cells and circuits involved in chemosensory processing and thereby change perception. Given our limited understanding of SARS-CoV-2 pathogenesis, we propose future experiments to elucidate disease mechanisms and highlight the relevance of this ongoing work to understanding how the virus might alter brain function more broadly.

Olfactory Dysfunction in COVID-19 Patients: Prevalence and Prognosis for Recovering Sense of Smell

While olfactory dysfunction associated with coronavirus disease 2019 (COVID-19) has attracted considerable interest, few studies have tracked outcomes at serial time points or beyond 2 weeks. Furthermore, data are conflicting regarding whether COVID-19 severity correlates with degree of olfactory dysfunction. This prospective case-control study analyzed prevalence and severity of subjective loss of smell in outpatients (n = 23) and inpatients (n = 20) with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection vs healthy controls (n = 25). Olfactory dysfunction was reported more commonly in COVID-19 patients than in healthy controls ( P < .001), and outpatients paradoxically reported loss of smell more commonly than inpatients ( P = .02). Headaches were present in 52% of patients with olfactory dysfunction. Anosmia or hyposmia persisted beyond 5 days but most of the patients recovered by 30 days, suggesting favorable prognosis for olfaction. Differences between inpatients and outpatients are potentially reflective of timeline of olfactory symptoms and contextual factors, underscoring the importance of corroborative objective testing, coupled with careful tracking of temporal relationships.

THE NERVOUS SYSTEM DAMAGE IN COVID-19 PATIENTS

Based on the available publications, the article systematizes the forms of damage to the central nervous system in СOVID-19patients. Along with a description of clinical manifestations, pathogenesis, methods of laboratory, instrumental and radiological diagnosis with the discussion of the nosological forms. An interdisciplinary approach and international cooperation are required to study the problems pathogenesis, course, outcomes, and the development of new methods of diagnosis and treatment.