Pathophysiological Mechanisms and Neurological Manifestations in COVID-19

Clinical features of COVID-19-related optic neuritis: a retrospective study

Objective

This retrospective study aimed to investigate the clinical features of optic neuritis associated with COVID-19 (COVID-19 ON), comparing them with neuromyelitis optica-associated optic neuritis (NMO-ON), myelin oligodendrocyte glycoprotein-associated optic neuritis (MOG-ON), and antibody-negative optic neuritis (antibody-negative ON).

Methods

Data from 117 patients (145 eyes) with optic neuritis at the Shantou International Eye Center (March 2020-June 2023) were categorized into four groups based on etiology: Group 1 (neuromyelitis optica-related optic neuritis, NMO-ON), Group 2 (myelin oligodendrocyte glycoprotein optic neuritis, MOG-ON), Group 3 (antibody-negative optic neuritis, antibody-negative ON), and Group 4 (optic neuritis associated with COVID-19, COVID-19 ON). Characteristics of T2 and enhancement in orbital magnetic resonance imaging (MRI) were assessed. Best-corrected visual acuity (BCVA) was compared before treatment, at a short-term follow-up (14 days), and at the last follow-up after treatment.

Results

The COVID-19-associated optic neuritis (COVID-19 ON) group exhibited 100% bilateral involvement, significantly surpassing other groups (P < 0.001). Optic disk edema was observed in 100% of COVID-19 ON cases, markedly differing from neuromyelitis optica-related optic neuritis (NMO-ON) (P = 0.023). Orbital magnetic resonance imaging (MRI) revealed distinctive long-segment lesions without intracranial involvement in T1-enhanced sequences for the COVID-19 ON group compared to the other three groups (P < 0.001). Discrepancies in optic nerve sheath involvement were noted between the COVID-19 ON group and both NMO-ON and antibody-negative optic neuritis (antibody-negative ON) groups (P = 0.028). Before treatment, no significant difference in best-corrected visual acuity (BCVA) existed between the COVID-19 ON group and other groups. At the 14-day follow-up, BCVA in the COVID-19 ON group outperformed the NMO-ON (P < 0.001) and antibody-negative ON (P = 0.028) groups, with no significant difference observed compared to the myelin oligodendrocyte glycoprotein optic neuritis (MOG-ON) group. At the last follow-up after treatment, BCVA in the COVID-19 ON group significantly differed from the NMO-ON group (P < 0.001).

Conclusion

Optic neuritis associated with COVID-19 (COVID-19 ON) predominantly presents with bilateral onset and optic disk edema. Orbital magnetic resonance imaging (MRI) demonstrates that COVID-19 ON presents as long-segment enhancement without the involvement of the intracranial segment of the optic nerve in T1-enhanced images. Glucocorticoid therapy showed positive outcomes.

Neurological manifestations and complications of COVID-19 in patients admitted to a tertiary care center in Nepal during the second wave

Neurological symptoms and signs of Coronavirus disease-19 (COVID-19) can accompany, follow, or precede respiratory symptoms and signs; hence, they are important in the diagnosis and management of COVID-19 patients. In this retrospective study conducted during the second wave of COVID-19, we included all patients diagnosed with COVID-19 using real-time polymerase chain reaction and admitted to the Tribhuvan University Teaching Hospital between June 2021 and October 2021. The patients were categorized into 2 groups: group A (with neurological manifestations or complications) and Group-B (without neurological manifestations or complications). The 2 groups were compared in terms of intensive care unit (ICU) admission, need for ventilatory support, length of hospital stay, and various outcomes. The study included 235 participants ranging in age from 13 to 102 years (mean age = 54 years, standard deviation = 18). Among the participants, 54.50% were male. The proportion of individuals in group A was higher (59.15%, N = 139) than that in Group-B (40.85%, N = 96). Notably, a significantly greater number of patients were admitted to the ICU in Group B than in Group A. However, there were no statistically significant differences in the need for ventilatory support or hospital stay between the 2 groups. Interestingly, group A showed a higher rate of improvement (Z = -3.1145, P = .00188, 95% CI), while Group-B had a higher rate of mortality (Z = 4.5562, P < .00001, 95% CI). Altered mental status and stroke have been specifically linked to poorer outcomes, whereas typical neurological manifestations, such as hyposmia, hypogeusia, dizziness, headache, and myalgia, are associated with better outcomes.

New-onset ANCA-associated vasculitis presenting with neuropathy after COVID-19 infection: A case report and literature review

Coronavirus Disease 2019 (COVID-19) is a viral infection caused by SARS-CoV-2, which can trigger autoimmune diseases such as antineutrophilic cytoplasmic antibody (ANCA) associated vasculitis (AAV) that affect small and medium-sized blood vessels in multiple organs. This study discusses a case with neuropathy and positive ANCA after COVID-19 infection and reviews the literature on AAV following COVID-19 infection. A 59-year-old man is presented that was referred to Shariati Hospital for evaluation of neurologic problems after a COVID-19 infection. Initially, he had flu-like symptoms. A few days later, he developed right distal upper and lower limb paresthesia. His electromyography (EMG) and nerve conduction velocity (NCV) results were consistent with polyneuropathy. Lumbar puncture (LP) was normal except for positive COVID-19 polymerase chain reaction (PCR). The patient's paresthesia worsened. Laboratory data showed leukocytosis, anemia, thrombocytosis, high erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Perinuclear anti-neutrophil cytoplasmic antibody (MPO-ANCA) was positive. According to the results, vasculitis was the main differential diagnosis. The sural nerve biopsy was performed, and the result was consistent with small to medium-sized vessel vasculitis. The patient was diagnosed with COVID-induced AAV. He was prescribed methylprednisolone and cyclophosphamide and was discharged with prednisolone and cotrimoxazole. In this study, a unique case of AAV induced by COVID-19 infection confirmed by nerve biopsy is presented. A review of the literature found 48 cases of new-onset AAV in adults and pediatrics after COVID-19 infection. Further research is needed to completely understand the relationship between COVID-19.

Facing the Challenges in the COVID-19 Pandemic Era: From Standard Treatments to the Umbilical Cord-Derived Mesenchymal Stromal Cells as a New Therapeutic Strategy

Coronavirus disease 2019 (COVID-19), the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which counts more than 650 million cases and more than 6.6 million of deaths worldwide, affects the respiratory system with typical symptoms such as fever, cough, sore throat, acute respiratory distress syndrome (ARDS), and fatigue. Other nonpulmonary manifestations are related with abnormal inflammatory response, the "cytokine storm", that could lead to a multiorgan disease and to death. Evolution of effective vaccines against SARS-CoV-2 provided multiple options to prevent the infection, but the treatment of the severe forms remains difficult to manage. The cytokine storm is usually counteracted with standard medical care and anti-inflammatory drugs, but researchers moved forward their studies on new strategies based on cell therapy approaches. The perinatal tissues, such as placental membranes, amniotic fluid, and umbilical cord derivatives, are enriched in mesenchymal stromal cells (MSCs) that exert a well-known anti-inflammatory role, immune response modulation, and tissue repair. In this review, we focused on umbilical-cord-derived MSCs (UC-MSCs) used in in vitro and in vivo studies in order to evaluate the weakening of the severe symptoms, and on recent clinical trials from different databases, supporting the favorable potential of UC-MSCs as therapeutic strategy.

Thirty-Day Outcomes of Young and Middle-Aged Adults Admitted with Severe COVID-19 in Uganda: A Retrospective Cohort Study

Background

There is scarcity of data regarding young and middle-aged adults hospitalized with severe Corona Virus Disease 2019 (COVID-19) in Africa. In this study, we describe the clinical characteristics and 30-day survival among adults aged 18 to 49 years admitted with severe COVID-19 in Uganda.

Methods

We reviewed treatment records of patients admitted with severe COVID-19 across five COVID-19 treatment units (CTU) in Uganda. We included individuals aged 18 to 49 years, who had a positive test or met the clinical criteria for COVID-19. We defined severe COVID-19 as having an oxygen saturation <94%, lung infiltrates >50% on imaging and presence of a co-morbidity that required admission in the CTU. Our main outcome was the 30-day survival from the time of admission. We used a Cox proportional hazards model to determine the factors associated with 30-day survival at a 5% level of significance.

Results

Of the 246 patient files reviewed, 50.8% (n = 125) were male, the mean ± (standard deviation) age was 39 ± 8 years, majority presented with cough, 85.8% (n = 211) and median C-reactive protein (interquartile range) was 48 (47.5, 178.8) mg/L. The 30-day mortality was 23.9% (59/246). At admission, anemia (hazard ratio (HR): 3.00, 95% confidence interval (CI), 1.32-6.82; p = 0.009) and altered mental state (GCS <15) (HR: 6.89, 95% CI: 1.48-32.08, p = 0.014) were significant predictors of 30-day mortality.

Conclusion

There was a high 30-day mortality among young and middle-aged adults with severe COVID-19 in Uganda. Early recognition and targeted management of anemia and altered consciousness are needed to improve clinical outcomes.

Alteration of the blood-brain barrier by COVID-19 and its implication in the permeation of drugs into the brain

Diverse neurological symptoms have been reported in patients with SARS-CoV-2 disease (COVID-19), including stroke, ataxia, meningitis, encephalitis, and cognitive impairment. These alterations can cause serious sequelae or death and are associated with the entry of SARS-CoV-2 into the Central Nervous System (CNS). This mini-review discusses the main proposed mechanisms by which SARS-CoV-2 interacts with the blood-brain barrier (BBB) and its involvement in the passage of drugs into the CNS. We performed a search in PubMed with the terms “COVID-19” or “SARS-CoV-2” and “blood-brain barrier injury” or “brain injury” from the year 2019 to 2022. We found proposed evidence that SARS-CoV-2 infects neurovascular cells and increases BBB permeability by increasing the expression of matrix metalloproteinase-9 that degrades type IV collagen in the basement membrane and through activating RhoA, which induces restructuring of the cytoskeleton and alters the integrity of the barrier. The breakdown of the BBB triggers a severe inflammatory response, causing the cytokine storm (release of IL-1β, IL-6, TNF-α, etc.) characteristic of the severe phase of COVID-19, which includes the recruitment of macrophages and lymphocytes and the activation of astrocytes and microglia. We conclude that the increased permeability of the BBB would allow the passage of drugs that would not reach the brain in a normal physiological state, thus enhancing certain drugs’ beneficial or adverse effects. We hope this article will encourage research on the impact of drugs on patients with COVID-19 and recovered patients with sequelae, focusing mainly on possible dose adjustments and changes in pharmacokinetic parameters.

F-18 FDG PET/CT as a One-Stop Shop Imaging Modality for Assessment of Neurologic and Pulmonary Manifestations of COVID-19

Neurologic manifestations are now being increasingly encountered in patients who are admitted for respiratory symptoms of COVID-19. A 67-year-old male with a recent history of Wernicke's aphasia was referred to the nuclear medicine department for risk stratification of malignancy in pulmonary nodule by 18F-FDG PET-CT scan. PET-CT revealed decreased metabolic activity in the left temporoparietal lobe of the brain consistent with recent CVA and excluded malignancy in the pulmonary nodule with low-grade metabolic activity. Incidentally noted, new bilateral pulmonary hypermetabolic ground glass opacities rising suspicious for covid-19 infection which was confirmed by PCR of nasopharyngeal mucosa sample. These findings highlight the value of 18FFDG PET-CT in the assessment of COVID-19 infection especially in non-pulmonary presentations like early neurologic manifestation.

Post-Acute Effect of SARS-CoV-2 Infection on the Cardiac Autonomic Function

Background

Methods

Results

Conclusion

EEG background frequency is associated with discharge outcomes in non-ICU hospitalized patients with COVID-19

Objective

To assess risk factors for encephalopathy in non-ICU hospitalized patients with COVID-19 and the effect of encephalopathy on short-term outcomes.

Methods

We collected clinical and electrophysiological characteristics of fifty patients with COVID-19 infection admitted to a ward service and who had an electroencephalogram (EEG) performed. Associations with short-term outcomes including hospital length of stay and discharge disposition were determined from univariate and multivariate statistical analysis.

Results

Clinical delirium was associated with encephalopathy on EEG, cefepime use was associated with increased length of stay, and of all factors analyzed, background frequency on EEG alone was correlated with discharge disposition.

Conclusion

Encephalopathy is one of the major determinants of short-term outcomes in hospitalized non-ICU patients with COVID-19.

Serum Brain-Derived Neurotrophic Factor (BDNF) in COVID-19 Patients and its Association with the COVID-19 Manifestations

COVID-19 is a systematic disease that frequently implies neurological and non-neurological manifestations, predominantly by inducing hypoxia. Brain-derived neurotrophic factor (BDNF) is a key factor in regulating functions of nervous and respiratory systems and has been strongly related to hypoxia. Therefore, this study planned to investigate BDNF association with the COVID-19 manifestations especially neurological impairments and the infection-induced hypoxia. We enrolled sixty-four COVID-19 patients and twenty-four healthy individuals in this study. Patients were divided into two groups, with and without neurological manifestations, and their serum BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA). COVID-19 patients had significantly lower BDNF levels than healthy individuals (p = 0.023). BDNF levels were significantly lower in patients with neurological manifestations compared to healthy individuals (p = 0.010). However, we did not observe a statistically significant difference in BDNF levels between patients with and without neurological manifestations (p = 0.175). BDNF’s levels were significantly lower in patients with CNS manifestations (p = 0.039) and higher in patients with fever (p = 0.03) and dyspnea (p = 0.006). Secondly, BDNF levels have a significant negative association with oxygen therapy requirement (p = 0.015). These results strongly suggest the critical association between dysregulated BDNF and hypoxia in promoting COVID-19 manifestations, particularly neurological impairments.

Non-hypertension-associated Posterior Reversible Encephalopathy Syndrome in COVID-19

Background

Coronavirus disease-2019 (COVID-19) infection-related neurological events are not uncommon but presenting as posterior reversible encephalopathy syndrome (PRES) without hypertension is a very rare presentation and requires a high index of suspicion.

Case summary

We report a case of a middle-aged female who presented with severe COVID-19 disease with no neurological symptoms. She complained of diminished vision on day 7 of the illness and underwent an MRI brain to rule out an ischemic stroke but the findings were suggestive of PRES. She had no episode of hypertension during the hospital stay. Probably severe COVID-related inflammation was the reason for such a presentation. Conservative management resolved the issue and her symptoms weaned off.

Conclusion

Severe COVID disease can lead to PRES-like symptoms and requires neuroimaging to validate it. Conservative management is the best treatment for such patients.

How to cite this article

Sharma D, Tomar DS, Gupta S. Non-hypertension-associated Posterior Reversible Encephalopathy Syndrome in COVID-19. Indian J Crit Care Med 2022;26(5):641–642.

Clinical, Laboratory and Imaging Characteristics of Hospitalized COVID-19 Patients with Neurologic Involvement; a Cross-Sectional Study

Introduction

Although neurologic involvement and neuroimaging abnormalities have been frequently identified in COVID-19 patients, the underlying factors remain unclear. In this study, we assessed the association of the neurological manifestations and neuroimaging features of hospitalized COVID-19 patients with their clinical, laboratory, and imaging characteristics.

Methods

This multicenter cross-sectional study was conducted between September 2020 and March 2021 at two large academic hospitals in Tehran, Iran. We used census sampling from medical records to enroll hospitalized patients with a positive COVID-19 Polymerase chain reaction (PCR) test who underwent brain imaging due to presenting any acute neurologic symptom during hospital stay.

Results

Of the 4372 hospitalized patients with COVID-19, only 211 met the inclusion criteria (35.5% with severe infection). Central nervous system and psychiatric manifestations were significantly more common in severe cases (p ≤ 0.044). Approximately, 30% had a new abnormality on their neuroimaging, with ischemic (38/63) and hemorrhagic (16/63) insults being the most common. The most frequent reasons that provoked cranial imaging were headache (27%), altered consciousness (25.6%), focal neurologic signs (19.9%), and delirium (18%). Analysis revealed a positive correlation for age, neutrophilia, lymphopenia, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) with the emergence of neuroimaging abnormalities (p ≤ 0.018). In addition, patients with new neuroimaging abnormalities had a significantly higher lung CT score than those without any pathologic findings (11.1 ± 4.8 vs. 5.9 ± 4.8, p < 0.001).

Conclusion

Approximately 30% of the study population had various acute neuroimaging findings. The lung CT score, neutrophil count, and age were strong predictors of acute neuroimaging abnormalities in hospitalized COVID-19 patients.

New-Onset Refractory Status Epilepticus Secondary to COVID-19 Infection in Adults: A Systematic Review

BACKGROUND

New-onset refractory status epilepticus (NORSE) has been reported in the scientific literature as a phenomenon associated with the COVID-19 infection. Given the resurgence of the newer variants of COVID-19 added with its multi-system manifestations, this project was conducted to study the clinical picture of NORSE secondary to COVID-19 infection.

METHODS

Three electronic databases were searched using an extensive search strategy from November 2019 to December 2021. Patients reporting NORSE secondary to COVID-19 were included in this review. The status epilepticus severity score (STESS) was calculated by the study authors for individual patients. Statistical analysis was performed using SPSS version 26 with a p-value <0.05 as statistically significant.

RESULTS

After screening, 12 patients were included in this study with a mean age of 61.6 ± 19.0-year olds. The most common type of status epilepticus reported in our study population was non-convulsive status epilepticus (NCSE) (7 out of 12 patients, 58.3%). The linear regression model revealed that STESS scores were significantly influenced by patients' age (p = 0.004) and intra-hospital occurrence (IHO) of status epilepticus (p = 0.026). Overall, 8 patients (66.7%) were discharged without complications.

CONCLUSION

Given the observed association of STESS with the aging population and IHO of status epilepticus, special attention is due to the caretakers of this population, while further studies are needed to further build upon this review.

Clinical Characteristics and Outcomes of Critically Ill Neurological Patients with COVID-19 Infection in Neuro-intensive Care Unit: A Retrospective Study

Background

There are insufficient data about clinical outcomes in critically ill neurological patients with concomitant coronavirus disease (COVID-19). This study describes the clinical characteristics, predictors of mortality, and clinical outcomes in COVID-19-positive neurological patients managed in a dedicated COVID-19 neurointensive care unit (CNICU).

Methods

This single-center, retrospective cohort study was conducted in critically ill neurological and neurosurgical patients with concomitant COVID-19 infection admitted to the CNICU at the National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, from July to November 2020. Patients’ demographic, clinical, laboratory, imaging, treatment, and outcome data were retrieved from the manual and electronic medical records. Predictors of mortality and neurological outcome were identified using logistic regression.

Results

During the study period, 50 COVID-19-positive neurological patients were admitted to the CNICU. Six patients were excluded from the analysis as they were managed in the CNICU for <24 hours. A poor outcome, defined as death or motor Glasgow Coma Scale <5 at hospital discharge, was observed in 34 of 44 patients (77.27%) with inhospital mortality in 26 of 44 patients (59%). Worst modified sequential organ failure assessment (MSOFA) score, lactate dehydrogenase maximum levels (LDH_max), and lymphocyte count were predictors of inhospital mortality with an odds ratio (OR) of 1.88, 1.01, and 0.87, respectively, whereas worst MSOFA and LDH_max levels were predictors for poor neurological outcome with OR of 1.99 and 1.01, respectively.

Conclusions

Mortality is high in neurological patients with concomitant COVID-19 infection. Elevated inflammatory markers of COVID-19 suggest the role of systemic inflammation on clinical outcomes. Predictors of mortality and poor outcome were higher MSOFA score and elevated LDH levels. Additionally, lymphopenia was associated with mortality.

How to cite this article

Surve RM, Mishra RK, Malla SR, Kamath S, Chakrabarti DR, Kulanthaivelu K, et al. Clinical Characteristics and Outcomes of Critically Ill Neurological Patients with COVID-19 Infection in Neuro-intensive Care Unit: A Retrospective Study. Indian J Crit Care Med 2021;25(10):1126–1132.

The case of encephalitis in a COVID-19 pediatric patient

Background

The COVID-19 pandemic, induced by the worldwide spreading of the SARS-CoV-2, is well known for its clinical picture consistent with respiratory symptoms. If pulmonary complications are the most common manifestation of the disease, neurological problems are also significantly present, with complications including acute cerebrovascular events, encephalitis, Guillain-Barré and Miller Fisher syndromes, acute necrotizing hemorrhagic encephalopathy and hemophagocytic lymphohistiocytosis. These medical signs can be considered direct effects of the virus on the nervous system, para-infectious or post-infectious immune-mediated diseases, and neurological complications of the systemic effects of the SARS-CoV-2.

Case

In the present article, the encephalitis case in a 5-year-old girl positive for COVID-19 admitted to the emergency department complaining of fever and swelling in the neck is described. At this time, her neurological examination was unremarkable. Over the next few days, the fever went down and she experienced acute behavioral changes, mild confusion, and drowsiness. The brain MRI and electroencephalography (EEG) showed CNS involvement, suggestive of encephalitis.

Conclusion

The dramatic improvement of the symptoms after immunotherapy with corticosteroids reinforced the hypothesis of an immune-related mechanism.

Multiple Sclerosis Following SARS-CoV-2 Infection: A Case Report and Literature Review

Coronavirus disease 19 (COVID-19) is caused by severe acute respiratory coronavirus 2 (SARS-CoV-2). Apart from respiratory manifestations, COVID-19 can affect the nervous system due to its neurotropic features. Neurological manifestations and complications include headache, polyneuropathies, cerebrovascular accidents, seizures, encephalopathy, and demyelinating disease. We describe a case of multiple sclerosis, a demyelinating disease following COVID-19 infection, rarely reported in the literature. A 47-year-old female presented with fatigue, blurry vision, numbness, and signs of upper motor neuron lesions that had occurred three weeks after COVID-19 infection. Magnetic resonance imaging of the brain revealed demyelinating lesions in the periventricular area of both hemispheres, suggesting a demyelinating disease. A provisional diagnosis of multiple sclerosis was made. Her condition improved after the commencement of methylprednisolone.

18F-FDG-PET/CT in SARS-CoV-2 infection and its sequelae

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG-PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.

[18F-FDG-PET/CT in SARS-CoV-2 infection and its sequelae]

In recent months, much of the scientific efforts have focused on research on SARSCoV-2 infection and its consequences in humans. Still, many aspects remain unknown. It is known that the damage caused by SARS-CoV-2 is multifactorial and that its extension goes beyond lung inflammation and the acute phase, with the appearance of numerous complications and sequelae. To date, knowledge about the usefulness of 18F-FDG-PET/CT in the acute phase has been limited to the incidental detection of SARS-CoV-2 unsuspected pneumonia. Recent studies have been appearing collecting the findings of 18F-FDG- PET/CT in long COVID-19 or persistent COVID-19 state as well as the alterations caused after mass vaccination of the population in the metabolic studies. This work aims to review the existing literature focusing on these three issues and to briefly present our own preliminary experience.

Emerging COVID-19 Neurological Manifestations: Present Outlook and Potential Neurological Challenges in COVID-19 Pandemic

The unremitting coronavirus disease 2019 (COVID-19) pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) marked a year-long phase of public health adversaries and has severely compromised healthcare globally. Early evidence of COVID-19 noted its impact on the pulmonary and cardiovascular functions, while multiple studies in recent time shed light on its substantial neurological complications, though a comprehensive understanding of the cause(s), the mechanism(s), and their neuropathological outcomes is scarce. In the present review, we conferred evidence of neurological complications in COVID-19 patients and shed light on the SARS-CoV-2 infection routes including the hematogenous, direct/neuronal, lymphatic tissue or cerebrospinal fluid, or infiltration through infected immune cells, while the underlying mechanism of SARS-CoV-2 invasion to the central nervous system (CNS) was also discussed. In an up-to-date manner, we further reviewed the impact of COVID-19 in developing diverse neurologic manifestations associated with CNS, peripheral nervous system (PNS), skeletal muscle, and also pre-existing neurological diseases, including Alzheimer's disease, Parkinson's disease, multiple sclerosis, epilepsy, and myasthenia gravis. Furthermore, we discussed the involvement of key factors including age, sex, comorbidity, and disease severity in exacerbating the neurologic manifestations in COVID-19 patients. An outlook of present therapeutic strategies and state of existing challenges in COVID-19 management was also accessed. Conclusively, the present report provides a comprehensive review of COVID-19-related neurological complications and emphasizes the need for their early clinical management in the ongoing COVID-19 pandemic.

Immunopathology of SARS-COV-2 and Neurological Manifestations Caused by the Virus: A Review of the Literature

SARS-CoV-2 (Severe Acute Respiratory Syndrome), or the disease caused by the new coronavirus, the source of COVID-19, has rapidly turned into a pandemic, a danger with an impact on human health.

Various neurological manifestations associated with SARS-CoV-2 infection have been reported in the literature and are currently classified into central nervous system-related (headache, dizziness, cerebrovascular disease, epilepsy) and peripheral nervous system-related (anosmia, ageusia, muscle pain, Guillain-Barré syndrome). However, it remains difficult to establish a link between these neurological manifestations and the underlying mechanisms.

In the current context, physicians need to be aware of the broad spectrum of neurological symptoms associated with infection with this virus for early diagnosis and appropriate treatment.

In this review, we aim to highlight the pathways of SARS-CoV-2 virus invasion, the neurotropism of the virus and the immunopathological mechanisms underlying the neurological manifestations associated with COVID-19 disease.

Case Report: Behavioral Unresponsiveness in Acute COVID-19 Patients: The Utility of the Motor Behavior Tool-Revised and 18F-FDG PET/CT

Along with the propagation of COVID-19, emerging evidence reveals significant neurological manifestations in severely infected COVID-19 patients. Among these patients admitted to the intensive care unit (ICU), behavioral unresponsiveness may occur frequently, yet, there are still only a few cases reported and with rare descriptions of their motor behavior after pathological awakening. Several hypotheses regarding central lesions in these patients are conceivable. Here, we describe two acute SARS-CoV-2- infected patients who developed neurological symptoms evoking the condition of clinical cognitive motor dissociation (CMD). This diagnosis could be confirmed first by clinical observation of a dissociation between preserved cognitive abilities and lack of initial motor interaction and second, by performing ¹⁸F- FDG PET imaging. Accurate diagnosis led to an appropriate neuro-rehabilitation regimen with long-term neuro-rehabilitation leading to an improved outcome for both patients.