Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C1175175 (SARS)
 19,188 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Introduction: Since the beginning of the Covid-19 epidemic produced by SARS2-Cov virus, olfactory alterations have been observed at a greater frequency than in other coronavirus epidemics. While olfactory alterations may be observed in patients with rhinovirus, influenza virus, or parainfluenza virus infection, they are typically explained by nasal obstruction with mucus or direct epithelial damage; in the case of SARS-CoV-2, olfactory alterations may present without nasal congestion with mucus. We performed a study of patients presenting olfactory/gustatory alterations in the context of SARS-CoV-2 infection in order to contribute to the understanding of this phenomenon. Material and Methods: We performed a descriptive, cross-sectional, observational study of the clinical characteristics of olfactory/gustatory alterations using a self-administered, anonymous online questionnaire. Results: A total of 909 patients with SARS-CoV-2 infection and olfactory/gustatory alterations responded to the questionnaire in the 4-day data collection period; 824 cases (90.65%) reported simultaneous olfactory and gustatory involvement. Patients' responses to the questionnaire revealed ageusia (581, 64.1% of respondents), hypogeusia (256, 28.2%), dysgeusia (22, 2.4%), anosmia (752 82.8%), hyposmia (142, 15.6%), and dysosmia (8, 0.9%). Fifty-four percent (489) did not report concomitant nasal congestion or mucus. Conclusion: Olfactory alterations are frequent in patients with SARS-CoV-2 infection and is only associated with nasal congestion in half of the cases.
 ...
PMID:An Online Observational Study of Patients With Olfactory and Gustory Alterations Secondary to SARS-CoV-2 Infection. 3257 8

The respiratory condition COVID-19 arises in a human host upon the infection with SARS-CoV-2, a coronavirus that was first acknowledged in Wuhan, China, at the end of December 2019 after its outbreak of viral pneumonia. The full-blown COVID-19 can lead, in susceptible individuals, to premature death because of the massive viral proliferation, hypoxia, misdirected host immunoresponse, microthrombosis, and drug toxicities. Alike other coronaviruses, SARS-CoV-2 has a neuroinvasive potential, which may be associated with early neurological symptoms. In the past, the nervous tissue of patients infected with other coronaviruses was shown to be heavily infiltrated. Patients with SARS-CoV-2 commonly report dysosmia, which has been related to the viral access in the olfactory bulb. However, this early symptom may reflect the nasal proliferation that should not be confused with the viral access in the central nervous system of the host, which can instead be allowed by means of other routes for spreading in most of the neuroanatomical districts. Axonal, trans-synaptic, perineural, blood, lymphatic, or Trojan routes can gain the virus multiples accesses from peripheral neuronal networks, thus ultimately invading the brain and brainstem. The death upon respiratory failure may be also associated with the local inflammation- and thrombi-derived damages to the respiratory reflexes in both the lung neuronal network and brainstem center. Beyond the infection-associated neurological symptoms, long-term neuropsychiatric consequences that could occur months after the host recovery are not to be excluded. While our article does not attempt to fully comprehend all accesses for host neuroinvasion, we aim at stimulating researchers and clinicians to fully consider the neuroinvasive potential of SARS-CoV-2, which is likely to affect the peripheral nervous system targets first, such as the enteric and pulmonary nervous networks. This acknowledgment may shed some light on the disease understanding further guiding public health preventive efforts and medical therapies to fight the pandemic that directly or indirectly affects healthy isolated individuals, quarantined subjects, sick hospitalized, and healthcare workers.
 ...
PMID:Disentangling the Hypothesis of Host Dysosmia and SARS-CoV-2: The Bait Symptom That Hides Neglected Neurophysiological Routes. 3258 54

It has become clear since the pandemic broke out that SARS-CoV-2 virus causes reduction of smell and taste in a significant fraction of COVID-19 patients. The olfactory dysfunction often occurs early in the course of the disease, and sometimes it is the only symptom in otherwise asymptomatic carriers. The cellular mechanisms for these specific olfactory disturbances in COVID-19 are now beginning to be elucidated. Several very recent papers contributed to explaining the key cellular steps occurring in the olfactory epithelium leading to anosmia/hyposmia (collectively known as dysosmia) initiated by SARS-CoV-2 infection. In this Viewpoint, we discuss current progress in research on olfactory dysfunction in COVID-19 and we also propose an updated model of the SARS-CoV-2-induced dysosmia. The emerging central role of sustentacular cells and inflammatory processes in the olfactory epithelium are particularly considered. The proposed model of anosmia in COVID-19 does not answer unequivocally whether the new coronavirus exploits the olfactory route to rapidly or slowly reach the brain in COVID-19 patients. To answer this question, new systematic studies using an infectious virus and appropriate animal models are needed.
 ...
PMID:Anosmia in COVID-19: A Bumpy Road to Establishing a Cellular Mechanism. 3267 76

Smell and taste disorders are acknowledged as characteristic symptoms for SARS-CoV-2 infection by now. These symptoms have been linked to a neuroinvasive course of disease. In this study, we investigated five consecutive COVID-19 patients with a prolonged course of dysosmia and dysgeusia. Those with objectifiable alteration in taste or smell were subjected to MRI with contrast agent to investigate possible involvement of the central nervous system. We found dysosmia and dysgeusia to be mostly objectifiable, but no evidence for neuroinvasiveness could be detected by MRI in the late stage of the disease. Alterations in taste and smell could be objectified in most patients. Nevertheless, no evidence for a neuroinvasive potential could be identified by MRI, at least in the late stage of disease. We encourage medical professionals to conduct specialized examinations and MRIs in the acute stage of disease, which guarantees an optimum patient care.
 ...
PMID:Smell and Taste Disorders in COVID-19 Patients: Objective Testing and Magnetic Resonance Imaging in Five Cases. 3313 44