Spectrum of neurologic & neuroimaging manifestation in COVID-19

Topographical Distribution of Neuroanatomical Abnormalities Following COVID-19 Invasion : A Systematic Literature Review

PURPOSE

This systematic review is aimed at synthesising the literature base to date on the frequency and topographical distribution of neuroanatomical changes seen on imaging following COVID-19 invasion with a focus on both the acute and chronic phases of the disease.

METHODS

In this study, 8 databases were systematically searched to identify relevant articles published from December 2019 to March 2022 and supplemented with a manual reference search. Data were extracted from the included studies and narrative synthesis was employed to integrate the findings.

RESULTS

A total of 110 studies met the inclusion criteria and comprised 119,307 participants (including 31,073 acute and 143 long COVID-19 patients manifesting neurological alterations) and controls. Considerable variability in both the localisation and nature of neuroanatomical abnormalities are noted along the continuum with a wide range of neuropathologies relating to the cerebrovascular/neurovascular system, (sub)cortical structures (including deep grey and white matter structures), brainstem, and predominant regional and/or global alterations in the cerebellum with varying degrees of spinal involvement.

CONCLUSION

Structural regional alterations on neuroimaging are frequently demonstrated in both the acute and chronic phases of SARS-CoV‑2 infection, particularly prevalent across subcortical, prefrontal/frontal and cortico-limbic brain areas as well as the cerebrovascular/neurovascular system. These findings contribute to our understanding of the acute and chronic effects of the virus on the nervous system and has the potential to provide information on acute and long-term treatment and neurorehabilitation decisions.

Impact of Symptomatology, Clinical and Radiological Severity of COVID-19 on Pulmonary Function Test Results and Functional Capacity during Follow-Up among Survivors

One of the most commonly observed complications after COVID-19 is persistent pulmonary impairment. The aim of this study was to evaluate the impact of individual factors during the acute phase of COVID-19 on subsequent pulmonary function test results. The study involved 46 patients who were admitted to hospital due to respiratory failure caused by SARS-CoV-2 and who were assessed during follow-up visits at 3 and 9 months after discharge. Patients were divided into two subgroups according to the severity of respiratory failure. The severe group included patients requiring mechanical ventilation or HFNOT. The results of the study showed that a severe course of the disease was associated with a lower FVC and a higher FEV1/FVC ratio 3 months after discharge (both p < 0.05). In addition, it has been revealed that the length of hospitalization is a factor that negatively impacts the FEV1, FVC and TLC values measured at follow-up after 3 months. Furthermore, the obtained results identify the presence of cough in the acute phase of the disease as a factor having a positive impact on several PFT parameters (especially the FEV1/FVC ratio) as well as the 6MWT outcome after 3 months. The FVC improved significantly (p < 0.05) between the follow-up visits. The findings may indicate that COVID-19-induced respiratory dysfunction is usually temporary and spontaneously resolves during recovery. Recovery is slower in those who required more intensive oxygenation. The results of this study may be useful in identifying patients who require more intensive and longer rehabilitation after COVID-19.

SARS-CoV-2 Infection Impacts Carbon Metabolism and Depends on Glutamine for Replication in Syrian Hamster Astrocytes

COVID‐19 causes more than million deaths worldwide. Although much is understood about the immunopathogenesis of the lung disease, a lot remains to be known on the neurological impact of COVID‐19. Here we evaluated immunometabolic changes using astrocytes in vitro and dissected brain areas of SARS‐CoV‐2 infected Syrian hamsters. We show that SARS‐CoV‐2 alters proteins of carbon metabolism, glycolysis, and synaptic transmission, many of which are altered in neurological diseases. Real‐time respirometry evidenced hyperactivation of glycolysis, further confirmed by metabolomics, with intense consumption of glucose, pyruvate, glutamine, and alpha ketoglutarate. Consistent with glutamine reduction, the blockade of glutaminolysis impaired viral replication and inflammatory response in vitro. SARS‐CoV‐2 was detected in vivo in hippocampus, cortex, and olfactory bulb of intranasally infected animals. Our data evidence an imbalance in important metabolic molecules and neurotransmitters in infected astrocytes. We suggest this may correlate with the neurological impairment observed during COVID‐19, as memory loss, confusion, and cognitive impairment.

N, B. V, S. R, A. S. COVID-19: Invasion, pathogenesis and possible cure - A review

Today, Coronavirus disease (COVID-19) which is believed to be transmitted from bats to humans where the people of Wuhan city, China exposed to the wet animal market is an important international public health anxiety (Xiong et al., 2020). Although, several measures were undertaken to treat the diseases by various medical advancements and by a variety of treatment procedures, still the mortality is higher. Hence, social distancing has been implemented to control the current outburst of this pandemic which spreads through human to human transmission. As a consequence, there is a need to completely understand the route of invasions of the virus into the humans and the target receptors besides the other factors leading to the disease. Several vaccines and drugs have been developed with its own pros and cons. Many are still under the various phase of R&D and clinical trials. Here we highlight the possible entry molecules, pathogenesis, symptomatology, probable cure and the recently developed vaccines for the existing pandemic due to the COVID-19.

[COVID-19: neurological manifestations-update : What we know so far]

Beyond pulmonary presentation, COVID-19 infection can manifest with a variety of both acute and chronic neurologic and neuropsychiatric (concomitant) symptoms and diseases. Nonspecific symptoms such as headache, fatigue, olfactory and gustatory disturbance have been reported more frequently, and severe disease such as encephalopathy, encephalitis, and cerebrovascular events have been reported relatively rarely. The heterogeneity of neurologic and neuropsychiatric presentations is large, as well as the range of recorded prevalences. Older patients, pre-existing neurologic and non neurologic comorbidities and severe COVID-19 disease were associated with increased risk of severe neurologic complications and higher in-hospital mortality. Probable neurotropic pathomechanisms of SARS-CoV‑2 have been discussed, but a multifactorial genesis of neurologic/neuropsychiatric symptoms and disease beyond these is likely.