Immunogenetic landscape of COVID-19 infections related neurological complications

The human leukocyte antigen (HLA) is a critical component of antigen presentation and plays crucial role in conferring differential susceptibility and severity of diseases caused by viruses such as COVID-19. The immunogenetic profile of populations, BCG vaccination status, and a host of lifestyle factors might contribute to the observed variations in mortality rates due to COVID-19. These genetic, epigenetic, and environmental factors could widely influence infection dynamics and immune responses against COVID-19. The aim of this review is to provide an update on HLA association with SARS-CoV-2 infection in global populations and to highlight the possible neurological involvements. We also set out to explore the HLA immunogenetic markers related to COVID‐19 infections that can be used in screening high‐risk individuals for personalized therapies and in community-based vaccine development. © 2023 Elsevier Inc. All rights reserved.

Ginkgo Biloba and Long COVID: In Vivo and In Vitro Models for the Evaluation of Nanotherapeutic Efficacy.

Coronavirus infections are neuroinvasive and can provoke injury to the central nervous system (CNS) and long-term illness consequences. They may be associated with inflammatory processes due to cellular oxidative stress and an imbalanced antioxidant system. The ability of phytochemicals with antioxidant and anti-inflammatory activities, such as Ginkgo biloba, to alleviate neurological complications and brain tissue damage has attracted strong ongoing interest in the neurotherapeutic management of long COVID. Ginkgo biloba leaf extract (EGb) contains several bioactive ingredients, e.g., bilobalide, quercetin, ginkgolides A-C, kaempferol, isorhamnetin, and luteolin. They have various pharmacological and medicinal effects, including memory and cognitive improvement. Ginkgo biloba, through its anti-apoptotic, antioxidant, and anti-inflammatory activities, impacts cognitive function and other illness conditions like those in long COVID. While preclinical research on the antioxidant therapies for neuroprotection has shown promising results, clinical translation remains slow due to several challenges (e.g., low drug bioavailability, limited half-life, instability, restricted delivery to target tissues, and poor antioxidant capacity). This review emphasizes the advantages of nanotherapies using nanoparticle drug delivery approaches to overcome these challenges. Various experimental techniques shed light on the molecular mechanisms underlying the oxidative stress response in the nervous system and help comprehend the pathophysiology of the neurological sequelae of SARS-CoV-2 infection. To develop novel therapeutic agents and drug delivery systems, several methods for mimicking oxidative stress conditions have been used (e.g., lipid peroxidation products, mitochondrial respiratory chain inhibitors, and models of ischemic brain damage). We hypothesize the beneficial effects of EGb in the neurotherapeutic management of long-term COVID-19 symptoms, evaluated using either in vitro cellular or in vivo animal models of oxidative stress.

The CH24H metabolite, 24HC, blocks viral entry by disrupting intracellular cholesterol homeostasis.

Cholesterol-24-hydroxylase (CH24H or Cyp46a1) is a reticulum-associated membrane protein that plays an irreplaceable role in cholesterol metabolism in the brain and has been well-studied in several neuro-associated diseases in recent years. In the present study, we found that CH24H expression can be induced by several neuroinvasive viruses, including vesicular stomatitis virus (VSV), rabies virus (RABV), Semliki Forest virus (SFV) and murine hepatitis virus (MHV). The CH24H metabolite, 24-hydroxycholesterol (24HC), also shows competence in inhibiting the replication of multiple viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 24HC can increase the cholesterol concentration in multivesicular body (MVB)/late endosome (LE) by disrupting the interaction between OSBP and VAPA, resulting in viral particles being trapped in MVB/LE, ultimately compromising VSV and RABV entry into host cells. These findings provide the first evidence that brain cholesterol oxidation products may play a critical role in viral infection.

Severe West Nile Virus Neuroinvasive Disease: Clinical Characteristics, Short- and Long-Term Outcomes.

West Nile Virus Neuroinvasive Disease (WNV NID) requires prolonged intensive care treatment, resulting in high mortality and early disability. Long-term results are lacking. We have conducted an observational retrospective study with a prospective follow-up of WNV NID patients treated at the Intensive Care Unit (ICU), University Hospital for Infectious Diseases, Zagreb, Croatia, 2013-2018. Short-term outcomes were vital status, length of stay (LOS), modified Rankin Scale (mRS), and disposition at discharge. Long-term outcomes were vital status and mRS at follow-up. Twenty-three patients were identified, 78.3% males, median age 72 (range 33-84) years. Two patients (8.7%) died in the ICU, with no lethal outcomes after ICU discharge. The median ICU LOS was 19 days (range 5-73), and the median hospital LOS was 34 days (range 7-97). At discharge, 15 (65.2%) patients had moderate to severe/mRS 3-5, 6 (26.0%) had slight disability/mRS 2-1, no patients were symptom-free/mRS 0. Ten (47.6%) survivors were discharged to rehabilitation facilities. The median time to follow-up was nine months (range 6-69). At follow-up, seven patients died (30.5%), five (21.7%) had moderate to severe/mRS 3-5, one (4.3%) had slight disability/mRS 2-1, six (26.1%) had no symptoms/mRS 0, and four (17.4%) were lost to follow-up. Briefly, ten (43.5%) survivors improved their functional status, one (4.3%) was unaltered, and one (4.3%) aggravated. In patients with severe WNV NID, intensive treatment in the acute phase followed by inpatient rehabilitation resulted in significant recovery of functional status after several months.

Neurological manifestations associated with SARS-CoV-2 infection: an updated review

SARS-CoV-2 is a single-stranded RNA virus that belongs to the group of seven coronaviruses that affect humans, and its infection causes the COVID-19 disease. The association between the COVID-19 condition and risk factors of neurological manifestations is unclear to date. This review aims to update the main neurological manifestations associated with SARS-CoV-2 disease. First, we present the hypothesis of the neuroinvasion mechanisms of SARS-CoV-2. Then, we discuss the possible symptoms related to patients with COVID-19 infection in the central and peripheral nervous systems, followed by the perspectives of diagnosis and treatment of possible neurological manifesta-tions. The hypothesis of the neuroinvasion mechanism includes direct routes, as the virus crosses the blood-brain barrier or the ACE2 receptor pathway role, and indirect pathways, such as malfunctions of the immune system and vascular system dysregulation. Various studies report COVID-19 consequences, such as neuroanatomic alterations and cognitive impairment, besides peripheral condi-tions, such as anosmia, ageusia, and Guillain Barre Syndrome. However, the het-erogeneity of the studies about neurologic damage in patients after COVID-19 infection precludes any generalization of current findings. Finally, new studies are necessary to understand the adequate diagnosis, therapeutic method of early treatment, and risk group of patients for neurological manifestations of COVID-19 post-infection.Copyright © 2023, Instituto de Investigaciones Clinicas. All rights reserved.

SARS-Cov-2 Damage on the Nervous System and Mental Health.

The World Health Organization declared the pandemic situation caused by SARSCoV- 2 (Severe Acute Respiratory Syndrome Coronavirus-2) in March 2020, but the detailed pathophysiological mechanisms of Coronavirus disease 2019 (COVID-19) are not yet completely understood. Therefore, to date, few therapeutic options are available for patients with mildmoderate or serious disease. In addition to systemic and respiratory symptoms, several reports have documented various neurological symptoms and impairments of mental health. The current review aims to provide the available evidence about the effects of SARS-CoV-2 infection on mental health. The present data suggest that SARS-CoV-2 produces a wide range of impairments and disorders of the brain. However, a limited number of studies investigated the neuroinvasive potential of SARS-CoV-2. Although the main features and outcomes of COVID-19 are linked to severe acute respiratory illness, the possible damages on the brain should be considered, too.

Automated SSHHPS Analysis Predicts a Potential Host Protein Target Common to Several Neuroinvasive (+)ssRNA Viruses.

Within the viral genome, short stretches of homologous host pathogen sequences (SSHHPS) span the protease cleavage sites. To identify host proteins that may be cleaved during infection, we searched the human proteome for viral protease cleavage sites (~20 amino acids). We developed a sequence-to-symptom tool, automating the search and pairing process. We used the viral protein sequence, PHI-BLAST, and UniProt database for gene ontologies and disease relationships. We applied the tool to nine neuroinvasive viruses: Venezuelan and Eastern Equine encephalitis virus (VEEV, EEEV); severe acute respiratory syndrome (SARS, SARS-CoV-2); Middle East respiratory syndrome (MERS); EV-71; Japanese encephalitis virus (JEV); West Nile (WNV); and Zika (ZIKV). A comparison of the hits identified a protein common to all nine viruses called ADGRA2 (GPR124). ADGRA2 was a predicted hit of the 3CL main protease and papain-like protease (PLpro) of SARS-CoV-2. ADGRA2 is an adhesion G protein-coupled receptor and a key endothelial regulator of brain-specific angiogenesis. It is a Wnt7A/Wnt7B specific coactivator of beta-catenin signaling and is essential for blood-brain barrier (BBB) integrity in central nervous system (CNS) diseases. We show the cleavage of the predicted sequences in MYOM1, VWF by the SARS-CoV-2 PLpro; DNAH8 (dynein) by the MERS PLpro; ADGRA2 by the alphaviral VEEV nsP2 protease; and POT1 by the SARS-CoV-2 and MERS PLpro.

Features and management of acute and chronic neuro-COVID

This book underlines how COVID-19 is a multisystem inflammatory disease and how its pathophysiology can predispose to an increased risk of neurological issues. Several scientific pieces of evidence showes the mechanisms underlying the neuroinvasive capacity of the SARS-CoV-2 through direct viral damage and indirect processes entering the CNS by different routes including the vasculature, the olfactory and trigeminal nerves, the cerebrospinal fluid, and the lymphatic system inducing a direct neurotoxicity. Furthermore, the pro-inflammatory cytokine storm and oxidative stress can induce microglial activation and damage to the blood-brain barrier, culminating in widespread neuroinflammatory process. This acute neurotoxicity is clinically expressed as anosmia and ageusia, headache, nausea and vomiting, but other neurologic manifestations such as acute cerebrovascular diseases, consciousness impairment due to encephalitis, and meningitis are also described. The PNS can also be affected by infectious damage and clinical manifestations including Guillain-Barre syndrome, polyneuritis cranialis, and Miller Fisher Syndrome. A special issue concerns the neurocognitive dysfunction and altered consciousness manifested as delirium, agitation and confusion. Non-specific symptoms such as dizziness, seizures can accompany clinical pictures. Regardless of the admission diagnosis, a high percentage of patients discharged from ICUs develop disabilities affecting physical, cognitive and psychological activities. The symptoms such as asthenia, memory disturbances, depression, sleep disturbances, anxiety, and Post-traumatic stress disorder (PTSD), configure the so-called Post-intensive Care Syndrome (PICS). Multimodal management during the ICU stay and implementation of follow-up programs at patient discharge can reduce the incidence of this syndrome, improving the quality of life of surviving patients. In this complex scenario, a careful clinical approach through reliable diagnostic tools, and epidemiological studies aimed at evaluating the dimensions of the problem also in economic terms, is urgently needed. This book represents a valuable aid for all those healthcare professionals (intensivists, neurologist and psychiatrists, as well) involved in the management of these critically ill patients. (PsycInfo Database Record (c) 2022 APA, all rights reserved)

Status epilepticus and the presence of SARS-COV-2 in the cerebrospinal fluid: A case report.

A growing number of studies indicate a broad range of neurological manifestations, including seizures, occur in patients with COVID-19 infection. We report a 29-year-old female patient with status epilepticus and positive SARS-CoV-2 in the cerebrospinal fluid. Our findings support previous reports suggesting seizure as a possible symptom of COVID-19 infection.

West Nile Virus Neuroinfection in Humans: Peripheral Biomarkers of Neuroinflammation and Neuronal Damage.

Among emerging arthropod-borne viruses (arbovirus), West Nile virus (WNV) is a flavivirus that can be associated with severe neuroinvasive infections in humans. In 2018, the European WNV epidemic resulted in over 2000 cases, representing the most important arboviral epidemic in the European continent. Characterization of inflammation and neuronal biomarkers released during WNV infection, especially in the context of neuronal impairments, could provide insight into the development of predictive tools that could be beneficial for patient outcomes. We first analyzed the inflammatory signature in the serum of WNV-infected mice and found increased concentrations of several inflammatory cytokines. We next analyzed serum and cerebrospinal-fluid (CSF) samples from a cohort of patients infected by WNV between 2018 and 2019 in Hungary to quantify a large panel of inflammatory cytokines and neurological factors. We found higher levels of inflammatory cytokines (e.g., IL4, IL6, and IL10) and neuronal factors (e.g., BDNF, GFAP, MIF, TDP-43) in the sera of WNV-infected patients with neuroinvasive disease. Furthermore, the serum inflammatory profile of these patients persisted for several weeks after initial infection, potentially leading to long-term sequelae and having a deleterious effect on brain neurovasculature. This work suggests that early signs of increased serum concentrations of inflammatory cytokines and neuronal factors could be a signature underlying the development of severe neurological impairments. Biomarkers could play an important role in patient monitoring to improve care and prevent undesirable outcomes.

Neuropathological Aspects of SARS-CoV-2 Infection: Significance for Both Alzheimer's and Parkinson's Disease.

Evidence suggests that SARS-CoV-2 entry into the central nervous system can result in neurological and/or neurodegenerative diseases. In this review, routes of SARS-Cov-2 entry into the brain via neuroinvasive pathways such as transcribrial, ocular surface or hematogenous system are discussed. It is argued that SARS-Cov-2-induced cytokine storm, neuroinflammation and oxidative stress increase the risk of developing neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Further studies on the effects of SARS-CoV-2 and its variants on protein aggregation, glia or microglia activation, and blood-brain barrier are warranted.

A Retrospective Case Series of West Nile Neuroinvasive Disease in Two Tertiary Health Centers in Miami

Background. According to the Centers for Disease Control and Prevention, Florida was the third leading state in reported West Nile Neuroinvasive Disease (WNND) infections in 2020. WNND accounts for less than 1% of all West Nile virus (WNV) infections but carries a 10% mortality rate. The clinical characteristics of WNND have not been well described in Florida, an area with high mosquito activity. We hereby describe the clinical characteristics of WNND at two large hospitals in Miami. Methods. A 10-year retrospective study was performed at the University of Miami Hospital and Mount Sinai Medical Center to identify adult patients with confirmed WNV infection and neuroinvasion. Patient demographics, symptoms, neurological exam findings, laboratory diagnostics, intensive care unit (ICU), and hospital length of stay (LOS), and outcomes were described. Results. Eleven patients (73% male, mean age 64.4 ± 16.3 years) were identified between January 2010 to December 2020. The most prevalent comorbidities were HTN (64%) and DM (27%). The most common positive findings on the review of symptoms were fever (100%), confusion (81.8%), and headache (63.6%). The mean hospital LOS was 15.5 ±11.3 days, while the mean ICU LOS was 7.2 ± 11.9 days. The majority of patients (75%) spent more than 2 weeks in the ICU. Subject age was correlated with hospital LOS with a Pearson correlation of 0.624 (p=0.04). The survival rate was 91%. At the time of discharge, 80% of patients continued to have neurological symptoms. Figure 1: The percentage of subjects with different types of WNND. The section titled others, includes atypical presentations such as amnesia, focal neurological deficits (ataxia, hemiparesis), and myelopathy. Figure 2: Month and year of presentation at the time of hospital admission. Figure 3: Clinical presentation (%). Conclusion. This is the largest case series of WNND in Florida. Most cases occurred during summer 2020, which corresponds to the peak of the COVID-19 pandemic. Despite pandemic restrictions, we may have seen an increase in WNV cases due to higher-than-normal temperatures promoting mosquito abundance, increased outdoor activities due to the COVID-19 pandemic, and/or the redistribution of public health resources towards the pandemic rather than mosquito control. Residual neurological symptoms and impaired functional outcomes are common. Within the limitation of our small sample size, subject age appeared to correlate with hospital LOS. This correlation should be further explored in a larger case series. A high index of suspicion for WNND is suggested for patients presenting with fever and neurologic symptoms in Florida.

Atypical presentation of a neuroinvasive west nile fever

Background West Nile Virus is the most common cause of arboviral diseases and is endemic in the US. It can cause clinical presentation ranging from asymptomatic infection to neuroinvasive disease. Factors like old age, hematologic malignancies, and organ transplantation result in more severe disease. Case presentation An 85-year-old male farmer with coronary artery disease, congestive heart failure (CHF) and diabetes presented with sore throat, cough and shortness of breath. He was treated for CHF exacerbation and discharged but returned with fatigue, headache, Nausea, and vomiting. Imaging of the head and chest, inflammatory markers, COVID-19 PCR,and metabolic panel were all negative, . Then he became febrile, lethargic, and had altered mentation. He exhibited asymmetric weakness, bilateral positive Babinski and neck rigidity. Intravenous ceftriaxone, vancomycin, bactrim, and acyclovir were all initiated for meningoencephalitis of unclear etiology. CSF analysis showed 51 WBC, 0 RBC, 49% granulocytes, 55 glucose and 74 proteins. He was transferred to ICU with a glasgow coma score of 6-7 but was on a 'DO NOT INTUBATE' status. He developed acute anuric kidney injury which prompted emergent hemodialysis and vasopressor support had to be initiated. Family elected for palliative care, and he passed away shortly after. A day later, West Nile serology was reported positive as IGM in CSF. Also, both IgG and IgM were positive in serum Discussion This case demonstrates a rare, severe presentation of West Nile infection. Most persons infected with West Nile (WNV) virus are asymptomatic;symptoms are seen in only about 20 to 40 percent of infected patients [1] Serologic surveys and extrapolations from blood donor screening data indicate that neuroinvasive disease following infection is infrequent, with estimates ranging from 1 in 140 to 1 in 256 infections resulting in meningitis or encephalitis [2] The patient's risk factors for severe infection include elderly age and male sex. Age in particular is the most important risk factor for neurologic progression of disease.[3] The diagnosis can be suspected in patients who have altered mental status, signs of meningitis, unexplained fever, and focal neurologic deficit, especially when it presents in late summer months and has no obvious etiology. The CSF West Nile IgM antibody detection via ELISA is diagnostic as was in our case. The treatment is mainly supportive. The preventive measures including mosquito control, personal protective devices are of substantial importance. Vaccines are not available. [4 5 6] Conclusion The high index of suspicion is necessary to diagnose WNV neuroinvasive diseases especially in patients with atypical presentation. Seasonal clues must be considered.

Headache during SARS-CoV-2 infection as an early symptom associated with a more benign course of disease: a case-control study.

BACKGROUND AND PURPOSE: Headache is an important manifestation during SARS-CoV-2 infection. In this study, the aim was to identify factors associated with headache in COVID-19 and headache characteristics. METHODS: This case-control study includes COVID-19 hospitalized patients with pneumonia during March 2020. Controls comprise COVID-19 patients without headache and the cases are COVID-19 patients with headache. Demographic, clinical and laboratory data were obtained from the medical records. Headache characteristics were evaluated by semi-structured telephonic interview after discharge. RESULTS: Of a total of 379 COVID-19 patients, 48 (13%) developed headache. Amongst these, 30 (62%) were men and the median age was 57.9 (47-73) years. Headache was associated with younger age, fewer comorbidities and reduced mortality, as well as with low levels of C-reactive protein, mild acute respiratory distress syndrome and oropharyngeal symptoms. A logistic multiple regression model revealed that headache was directly associated with D-dimer and creatinine levels, the use of high flow nasal cannula and arthromyalgia, whilst urea levels, beta-lactamic treatment and hypertension were negatively associated with headache. COVID-19-associated headache characteristics were available for 23/48 (48%) patients. Headache was the onset symptom in 8/20 (40%) patients, of mild or moderate intensity in 17/20 (85%) patients, with oppressive characteristics in 17/18 (94%) and of holocranial 8/19 (42%) or temporal 7/19 (37%) localization. CONCLUSIONS: Our results show that headache is associated with a more benign SARS-CoV-2 infection. COVID-19-associated headache appears as an early symptom and as a novel headache with characteristics of headache attributed to systemic viral infection. Further research addressing the underlying mechanisms to confirm these findings is warranted.

The Immunopathogenesis of Neuroinvasive Lesions of SARS-CoV-2 Infection in COVID-19 Patients.

The new coronavirus disease COVID-19 was identified in December 2019. It subsequently spread across the world with over 125 M reported cases and 2.75 M deaths in 190 countries. COVID-19 causes severe respiratory distress; however, recent studies have reported neurological consequences of infection by the COVID-19 virus SARS-CoV-2 even in subjects with mild infection and no initial neurological effects. It is likely that the virus uses the olfactory nerve to reach the CNS and that this transport mechanism enables virus access to areas of the brain stem that regulates respiratory rhythm and may even trigger cell death by alteration of these neuronal nuclei. In addition, the long-term neuronal effects of COVID-19 suggest a role for SARS-CoV-2 in the development or progression of neurodegerative disease as a result of inflammation and/or hypercoagulation. In this review recent findings on the mechanism(s) by which SARS-CoV-2 accesses the CNS and induces neurological dysregulation are summarized.

Neurological manifestations and neuroimaging findings in patients with SARS-CoV2-a systematic review.

BACKGROUND: The COVID-19 pandemic has drastically affected everyone in a hit or miss manner. Since it began, evidence of the neuro-invasive potential of the virus has been intensifying significantly. Several pathways have been hypothesized to elucidate the neurotropic nature of SARS-CoV2. It is the need of the hour to collect vital information. OBJECTIVE: To evaluate and correlate the neuro-radiological and neurological manifestations in patients diagnosed with SARS-CoV2.To identify neuro-invasive pathways of COVID infection. METHODS: Relevant studies were identified through four databases-the Cochrane Library, PubMed, Science Direct, and Web of Science. These were searched using relevant keywords-"COVID-19," "SARS-CoV2," "neurological manifestations," "neuroimaging," "CT," and "MRI." Relevant articles were screened according to a pre-defined inclusion and exclusion criteria from December 2019 to August 2020. RESULTS: Our review included a total of 63 full text publications with 584 patients, composed mainly of observational studies, case reports, and case series. The most common neurological manifestations associated with COVID-19 were altered mental status, stroke, and paralysis. About 17.85% patients who underwent neuroimaging were found to be having ischemic changes suggestive of a stroke. This was followed by hemorrhagic changes as the second most common finding. The most commonly involved vessel was the Middle Cerebral Artery. Besides stroke, we found that SARS-CoV2 could be the cause for new-onset seizures, Guillain-Barre Syndrome, encephalitis, and many other severe neurological diseases. CONCLUSION: The information that we have obtained so far will prove dynamic to healthcare providers working against the COVID-19 pandemic. It is necessary to be aware of these atypical neurological findings for the early diagnosis and treatment of COVID-19 infected patients. However, to completely understand the connection between SARS-CoV2 and the nervous system, further research is necessary.

Neurological symptoms in COVID-19: a cross-sectional monocentric study of hospitalized patients.

BACKGROUND: The SARS-Coronavirus-2 (SARS-CoV-2) invades the respiratory system, causing acute and sometimes severe pulmonary symptoms, but turned out to also act multisystematically with substantial impact on the brain. A growing number of studies suggests a diverse spectrum of neurological manifestations. To investigate the spectrum of symptoms, we here describe the neurological manifestations and complications of patients with proven SARS-CoV-2 infection who have been hospitalized at the RWTH University Hospital Aachen, Germany. METHODS: Between March and September 2020, we evaluated common symptoms, clinical characteristics, laboratory (including cerebrospinal fluid (CSF) analysis), radiological, and electroencephalography (EEG) data from 53 patients admitted with a positive SARS-CoV-2 polymerase chain reaction (PCR). We used the Montreal Cognitive Assessment Test (MoCA) to screen for cognitive impairment, when feasible. We compared critically ill and non-critically ill patients categorized according to the presence of Acute Respiratory Distress Syndrome (ARDS). RESULTS: Major clinical neurological features of hospitalized COVID-19 patients were coordination deficits (74%), cognitive impairment (61.5%), paresis (47%), abnormal reflex status (45%), sensory abnormalities (45%), general muscle weakness and pain (32%), hyposmia (26%), and headache (21%). Patients with ARDS were more severely affected than non-ADRS patients. 29.6% of patients with ARDS presented with subarachnoid bleedings, and 11.1% showed ischemic stroke associated with SARS-CoV-2 infection. Cognitive deficits mainly affected executive functions, attention, language, and delayed memory recall. We obtained cerebrospinal fluid (CSF) by lumbar puncture in nine of the 53 patients, none of which had a positive SARS-CoV-2 PCR. CONCLUSIONS: In line with previous findings, our results provide evidence for a range of SARS-CoV-2-associated neurological manifestations. 26% of patients reported hyposmia, emphasizing the neuro-invasive potential of SARS-CoV-2, which can enter the olfactory bulb. It can therefore be speculated that neurological manifestations may be caused by direct invasion of the virus in the CNS; however, PCR did not reveal positive intrathecal SARS-CoV-2. Therefore, we hypothesize it is more likely that the para-infectious severe pro-inflammatory impact of COVID-19 is responsible for the neurological deficits including cognitive impairment. Future studies with comprehensive longitudinal assessment of neurological deficits are required to determine potential long-term complications of COVID-19.

The neuropathological impact of COVID-19: a review.

BACKGROUND: The Coronavirus disease 2019 (COVID-19) outbreak has become a challenging global issue after its emergence in December 2019. Due to the high adaptation of the virus, COVID-19 demonstrated a high transmission and infectivity potentials. Several studies demonstrated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induce deleterious neurological manifestations through interacting with the central nervous system (CNS). MAIN BODY: The neuroinvasive potential of SARS-CoV-2 might contribute to its fatal behavior. Understanding the underlying mechanisms of this novel neuropathogen might contribute to the development of effective therapeutic strategies. The manifestations of neural damage in COVID-19 patients ranged from headache to severe encephalopathy and progression of preexisting neural disorders, it is speculated that neuroinvasion is strongly linked to the fatal respiratory dysfunction. The underlying neuropathological impact of emerging pneumonia (COVID-19) is still unclear. CONCLUSION: This review demonstrated the urgent need to understand the neuropathology of COVID-19, to manage the current borderless viral outbreak of SARS-CoV-2 and its comorbidities. Moreover, SARS-CoV-2 could be regarded as an opportunistic neuropathogen that affects several vital functions in the human body.

SARS-CoV-2 Infection: Symptoms of the Nervous System and Implications for Therapy in Neurological Disorders.

In this paper, the neurological aspects of COVID-19 are presented, which may be of significance for physicians. Knowledge about the neurological symptoms of COVID-19 infection should help physicians in diagnoses and in taking appropriate precautions, as some manifestations can appear before typical pulmonary symptoms. Various mechanisms of SARS-CoV-2 neuroinvasion are discussed and symptoms are described, which can be subdivided into manifestations of the central nervous system (CNS) (headache, dizziness, stroke, impaired consciousness, encephalitis, meningitis, seizures) and peripheral nervous system (PNS) (characteristic hyposmia and hypogeusia, Guillain Barré syndrome, myalgia). Additionally, the implications of COVID-19 infection for treatment of patients with common neurological diseases and their management is presented. It can be concluded that neurological symptoms are part of a clinical spectrum of COVID-19 infection, involving the CNS and PNS. COVID-19 may influence decisions regarding the treatment of neurological disorders, especially those with an immune background.

Potential neuroinvasive pathways of SARS-CoV-2: Deciphering the spectrum of neurological deficit seen in coronavirus disease-2019 (COVID-19).

Coronavirus disease-2019 (COVID-19) was declared a global pandemic on 11 March 2020. Scientists and clinicians must acknowledge that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has the potential to attack the human body in multiple ways simultaneously and exploit any weaknesses of its host. A multipronged attack could potentially explain the severity and extensive variety of signs and symptoms observed in patients with COVID-19. Understanding the diverse tactics of this virus to infect the human body is both critical and incredibly complex. Although patients diagnosed with COVID-19 have primarily presented with pulmonary involvement, viral invasion, and injury to diverse end organs is also prevalent and well documented in these patients, but has been largely unheeded. Human organs known for angiotensin-converting enzyme 2 (ACE2) expression including the gastrointestinal tract, kidneys, heart, adrenals, brain, and testicles are examples of extra pulmonary tissues with confirmed invasion by SARS-CoV-2. Initial multiple organ involvement may present with vague signs and symptoms to alert health care professionals early in the course of COVID-19. Another example of an ongoing, yet neglected element of the syndromic features of COVID-19, are the reported findings of loss of smell, altered taste, ataxia, headache, dizziness, and loss of consciousness, which suggest a potential for neural involvement. In this review, we further deliberate on the neuroinvasive potential of SARS-CoV-2, the neurologic symptomology observed in COVID-19, the host-virus interaction, possible routes of SARS-CoV-2 to invade the central nervous system, other neurologic considerations for patients with COVID-19, and a collective call to action.