Inflammation in neuroviral diseases

Post-viral fatigue in COVID-19: A review of symptom assessment methods, mental, cognitive, and physical impairment

Coronavirus 2 is responsible for Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2), and the main sequela is persistent fatigue. Post-viral fatigue is common and affects patients with mild, asymptomatic coronavirus disease-2019 (COVID-19). However, the exact mechanisms involved in developing post-COVID-19 fatigue remain unclear. Furthermore, physical and cognitive impairments in these individuals have been widely described. Therefore, this review aims to summarize and propose tools from a multifaceted perspective to assess COVID-19 infection. Herein, we point out the instruments that can be used to assess fatigue in long-term COVID-19: fatigue in a subjective manner or fatigability in an objective manner. For physical and mental fatigue, structured questionnaires were used to assess perceived symptoms, and physical and cognitive performance assessment tests were used to measure fatigability using reduced performance.

International Controlled Study of Revascularization and Outcomes Following COVID-Positive Mechanical Thrombectomy

Background and purpose

Previous studies suggest that mechanisms and outcomes in patients with COVID‐19‐associated stroke differ from those in patients with non‐COVID‐19‐associated strokes, but there is limited comparative evidence focusing on these populations. The aim of this study, therefore, was to determine if a significant association exists between COVID‐19 status with revascularization and functional outcomes following thrombectomy for large vessel occlusion (LVO), after adjustment for potential confounding factors.

Methods

A cross‐sectional, international multicenter retrospective study was conducted in consecutively admitted COVID‐19 patients with concomitant acute LVO, compared to a control group without COVID‐19. Data collected included age, gender, comorbidities, clinical characteristics, details of the involved vessels, procedural technique, and various outcomes. A multivariable‐adjusted analysis was conducted.

Results

In this cohort of 697 patients with acute LVO, 302 had COVID‐19 while 395 patients did not. There was a significant difference (p < 0.001) in the mean age (in years) and gender of patients, with younger patients and more males in the COVID‐19 group. In terms of favorable revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] grade 3), COVID‐19 was associated with lower odds of complete revascularization (odds ratio 0.33, 95% confidence interval [CI] 0.23–0.48; p < 0.001), which persisted on multivariable modeling with adjustment for other predictors (adjusted odds ratio 0.30, 95% CI 0.12–0.77; p = 0.012). Moreover, endovascular complications, in‐hospital mortality, and length of hospital stay were significantly higher among COVID‐19 patients (p < 0.001).

Conclusion

COVID‐19 was an independent predictor of incomplete revascularization and poor functional outcome in patients with stroke due to LVO. Furthermore, COVID‐19 patients with LVO were more often younger and had higher morbidity/mortality rates.

Characteristics of a COVID-19 Cohort With Large Vessel Occlusion: A Multicenter International Study

BACKGROUND

The mechanisms and outcomes in coronavirus disease (COVID-19)-associated stroke are unique from those of non-COVID-19 stroke.

OBJECTIVE

To describe the efficacy and outcomes of acute revascularization of large vessel occlusion (LVO) in the setting of COVID-19 in an international cohort.

METHODS

We conducted an international multicenter retrospective study of consecutively admitted patients with COVID-19 with concomitant acute LVO across 50 comprehensive stroke centers. Our control group constituted historical controls of patients presenting with LVO and receiving a mechanical thrombectomy between January 2018 and December 2020.

RESULTS

The total cohort was 575 patients with acute LVO; 194 patients had COVID-19 while 381 patients did not. Patients in the COVID-19 group were younger (62.5 vs 71.2; P < .001) and lacked vascular risk factors (49, 25.3% vs 54, 14.2%; P = .001). Modified thrombolysis in cerebral infarction 3 revascularization was less common in the COVID-19 group (74, 39.2% vs 252, 67.2%; P < .001). Poor functional outcome at discharge (defined as modified Ranklin Scale 3-6) was more common in the COVID-19 group (150, 79.8% vs 132, 66.7%; P = .004). COVID-19 was independently associated with a lower likelihood of achieving modified thrombolysis in cerebral infarction 3 (odds ratio [OR]: 0.4, 95% CI: 0.2-0.7; P < .001) and unfavorable outcomes (OR: 2.5, 95% CI: 1.4-4.5; P = .002).

CONCLUSION

COVID-19 was an independent predictor of incomplete revascularization and poor outcomes in patients with stroke due to LVO. Patients with COVID-19 with LVO were younger, had fewer cerebrovascular risk factors, and suffered from higher morbidity/mortality rates.

Headache Attributed to SARS-CoV-2 Infection or COVID-19 Related Headache-Not Migraine-like Problem-Original Research

BACKGROUND

Many studies have confirmed headache as one of the most common COVID-19-related neurological symptoms. There are some reports concerning migraine attacks during SARS-CoV-2 infection with an unusual course of migraine attack. Our aim was to recognize and characterize accurately the features of headaches accompanying this disease.

METHODS

Research based on questionnaire study gathered 100 randomly chosen medical healthcare employees who experienced symptoms associated with COVID-19 disease, 96 with confirmed COVID-19 (positive SARS-CoV-2 PCR laboratory test or positive rapid COVID-19 antigen test).

CONCLUSION

Headaches reported in the study did not fulfill criteria for migraine with/without aura, tension-type headache according to ICHD-3.

Matrix metalloproteinases are involved in the development of neurological complications in patients with Coronavirus disease 2019

BACKGROUND

Evidence show that Matrix metalloproteinases (MMPs) have been associated with neurological complications in the viral infections. Here in the current investigation, we intended to reveal if MMPs are potentially involved in the development of neurological symptoms in the patients with Coronavirus disease 2019 (COVID-19).

METHODS

The levels of MMPs, inflammatory cytokines, chemokines, and adhesion molecules were evaluated in the serum and cerebrospinal fluid (CSF) samples from 10 COVID-19 patients with neurological syndrome (NS) and 10 COVID-19 patients lacking NS. Monocytes from the CSF samples were treated with TNF-α and the secreted levels of MMPs were determined.

RESULTS

The frequency of monocytes were increased in the CSF samples of COVID-19 patients with NS compared to patients without NS. Levels of inflammatory cytokines IL-1β, IL-6, and TNF-α, chemokines CCL2, CCL3, CCL4, CCL7, CCL12, CXCL8, and CX3CL1, MMPs MMP-2, MMP-3, MMP-9, and MMP-12, and adhesion molecules ICAM-1, VCAM-1, and E-selectin were significantly increased in the CSF samples of COVID-19 patients with NS compared with patients without NS. Treatment of CSF-derived monocytes obtained from COVID-19 patients with NS caused increased production of MMP-2, MMP-3, MMP-9, and MMP-12.

CONCLUSIONS

Higher levels of inflammatory cytokines might promote the expression of adhesion molecules on blood-CSF barrier (BCSFB), resulting in facilitation of monocyte recruitment. Increased levels of CSF chemokines might also help to the trafficking of monocytes to CSF. Inflammatory cytokines might enhance production of MMPs from monocytes, leading to disruption of BCSFB (and therefore further infiltration of inflammatory cells to CSF) in COVID-19 patients with NS.

Clinical features and corresponding immune function status of recurrent viral polymerase chain reaction positivity in patients with COVID-19 : A meta- analysis and systematic review

INTRODUCTION

Coronavirus disease 2019 (COVID-19) was declared a global pandemic in March 2020. Since then, several studies have found COVID-19 patients with recurrent viral polymerase chain reaction (PCR) positivity.

METHODS

On May 6, 2021, an exhaustive literature search of the Web of Science, PubMed, Cochrane Library, Chinese National Knowledge Infrastructure databases, Embase, Wan Fang Data, VIP database, Sinomed database, BioRxiv, MedRxiv, and Research Square was conducted to find describing the laboratory indicators of recurrent and non-recurrent viral PCR positivity in patients with COVID-19. The data were statistically analyzed using STATA version 15.0.

RESULTS

In total, 22 studies-comprising 5154 laboratory-confirmed COVID-19 cases-were included in the analyses. Patients with less severe COVID-19 illness (i.e. those clinically classified as mild or common-type) seemed to exhibit recurrent PCR positivity more commonly than patients with more severe illness (i.e. those classified as severe or critical). There were also significant differences between the two groups in terms of the rates of headaches and dizziness, in addition to the levels of aspartate aminotransferase, C reactive protein, interleukin-6, and lactate dehydrogenase. Further, there were variations in the ratio of CD4+ T cells/CD8+ T cells on admission to the hospital.

CONCLUSION

In comparison to COVID-19 patients with non-recurrent viral PCR positivity, patients with recurrent virus PCR positivity seem to experience more severe immune function suppression upon hospital admission.

Neurological and Neuropsychiatric Impacts of COVID-19 Pandemic

BACKGROUND

Albeit primarily a disease of respiratory tract, the 2019 coronavirus infectious disease (COVID-19) has been found to have causal association with a plethora of neurological, neuropsychiatric and psychological effects. This review aims to analyze them with a discussion of evolving therapeutic recommendations.

METHODS

PubMed and Google Scholar were searched from 1 January 2020 to 30 May 2020 with the following key terms: "COVID-19", "SARS-CoV-2", "pandemic", "neuro-COVID", "stroke-COVID", "epilepsy-COVID", "COVID-encephalopathy", "SARS-CoV-2-encephalitis", "SARS-CoV-2-rhabdomyolysis", "COVID-demyelinating disease", "neurological manifestations", "psychosocial manifestations", "treatment recommendations", "COVID-19 and therapeutic changes", "psychiatry", "marginalised", "telemedicine", "mental health", "quarantine", "infodemic" and "social media". A few newspaper reports related to COVID-19 and psychosocial impacts have also been added as per context.

RESULTS

Neurological and neuropsychiatric manifestations of COVID-19 are abundant. Clinical features of both central and peripheral nervous system involvement are evident. These have been categorically analyzed briefly with literature support. Most of the psychological effects are secondary to pandemic-associated regulatory, socioeconomic and psychosocial changes.

CONCLUSION

Neurological and neuropsychiatric manifestations of this disease are only beginning to unravel. This demands a wide index of suspicion for prompt diagnosis of SARS-CoV-2 to prevent further complications and mortality.

Monocular visual loss as the presenting symptom of COVID-19 infection

BACKGROUND AND IMPORTANCE

Additional time is needed to determine the exact impact of COVID-19 on acute cerebrovascular disease incidence, but recently published data has correlated COVID-19 to large vessel occlusion strokes.

CLINICAL PRESENTATION

We report the first case of central retinal artery occlusion (CRAO) as the initial manifestation of COVID-19 infection. Subsequent neuroimaging revealed a large thrombus extending into the internal carotid artery.

CONCLUSION

This case illustrates the need to suspect COVID-19 infection in patients presenting with retinal arterial occlusion, including individuals who are asymptomatic or minimally symptomatic for COVID-19 infection.

Neurotropism of SARS-CoV-2 and its neuropathological alterations: Similarities with other coronaviruses

A novel coronavirus (SARS-CoV-2) emerged from Wuhan, China, and spread quickly around the world. In addition to fever, cough and shortness of breath, it was confirmed that the patients also have manifestations towards the central nervous system (CNS), especially those critically ill ones. In this review, we will discuss how SARS-CoV-2 gain access to the CNS and the possible consequences. Both SARS-CoV-2 and SARS-CoV-1 in 2002 share the same receptor angiotensin-converting enzyme 2 (ACE2), which can be found in the brain and mediate the disease process. Both direct attack of SARS-CoV-2 and the abnormal immune response in the CNS would contribute to the disease. Also, there is a relationship between SARS-CoV-2 and the occurrence of acute cerebrovascular diseases.

Cerebral ischemic and hemorrhagic complications of coronavirus disease 2019

BACKGROUND

The coronavirus disease 2019 is associated with neurological manifestations including stroke.

OBJECTIVES

We present a case series of coronavirus disease 2019 patients from two institutions with acute cerebrovascular pathologies. In addition, we present a pooled analysis of published data on large vessel occlusion in the setting of coronavirus disease 2019 and a concise summary of the pathophysiology of acute cerebrovascular disease in the setting of coronavirus disease 2019.

METHODS

A retrospective study across two institutions was conducted between 20 March 2020 and 20 May 2020, for patients developing acute cerebrovascular disease and diagnosed with coronavirus disease 2019. We performed a literature review using the PubMed search engine.

RESULTS

The total sample size was 22 patients. The mean age was 59.5 years, and 12 patients were female. The cerebrovascular pathologies were 17 cases of acute ischemic stroke, 3 cases of aneurysm rupture, and 2 cases of sinus thrombosis. Of the stroke and sinus thrombosis patients, the mean National Institute of Health Stroke Scale was 13.8 ± 8.0, and 16 (84.2%) patients underwent a mechanical thrombectomy procedure. A favorable thrombolysis in cerebral infarction score was achieved in all patients. Of the 16 patients that underwent a mechanical thrombectomy, the mortality incidence was five (31.3%). Of all patients (22), three (13.6%) patients developed hemorrhagic conversion requiring decompressive surgery. Eleven (50%) patients had a poor functional status (modified Rankin Score 3-6) at discharge, and the total mortality incidence was eight (36.4%).

CONCLUSIONS

Despite timely intervention and favorable reperfusion, the mortality rate in coronavirus disease 2019 patients with large vessel occlusion was high in our series and in the pooled analysis. Notable features were younger age group, involvement of both the arterial and venous vasculature, multivessel involvement, and complicated procedures due to the clot consistency and burden.

Neuroinvasion of SARS-CoV-2 may play a role in the breakdown of the respiratory center of the brain

The recent outbreak of the novel coronavirus, SARS-CoV-2, has emerged to be highly pathogenic in nature. Although lungs are considered as the primary infected organs by SARS-CoV-2, some of the other organs, including the brain, have also been found to be affected. Here, we have discussed how SARS-CoV-2 might infect the brain. The infection of the respiratory center in the brainstem could be hypothesized to be responsible for the respiratory failure in many COVID-19 patients. The virus might gain entry through the olfactory bulb and invade various parts of the brain, including the brainstem. Alternatively, the entry might also occur from peripheral circulation into the central nervous system by compromising the blood-brain barrier. Finally, yet another possible entry route could be its dispersal from the lungs into the vagus nerve via the pulmonary stretch receptors, eventually reaching the brainstem. Therefore, screening neurological symptoms in COVID-19 patients, especially toward the breakdown of the respiratory center in the brainstem, might help us better understand this disease.

Unraveling the Possible Routes of SARS-COV-2 Invasion into the Central Nervous System

PURPOSE OF REVIEW

To describe the possible neuroinvasion pathways of Severe Acute Respiratory Syndrome-related Coronavirus-2 (SARS-CoV-2), the virus responsible for the Coronavirus disease-19 (Covid-19) pandemic.

RECENT FINDINGS

We present data regarding the family of Coronaviruses (CoVs) and the central nervous system (CNS), and describe parallels between SARS-CoV-2 and other members of the family, which have been investigated in more depth and combine these findings with the recent advancements regarding SARS-CoV-2.

SUMMARY

SARS-CoV-2 like other CoVs is neuroinvasive, neurotropic and neurovirulent. Two main pathways of CNS penetration seem to be the strongest candidates, the hematogenous and the neuronal. Τhe olfactory route in particular appears to play a significant role in neuroinvasion of coronaviruses and SARS-CoV-2, as well. However, existing data suggest that other routes, involving the nasal epithelium in general, lymphatic tissue and the CSF may also play roles in SARS-CoV-2 invasion into the CNS.

Human Coronaviruses and Other Respiratory Viruses: Underestimated Opportunistic Pathogens of the Central Nervous System?

Respiratory viruses infect the human upper respiratory tract, mostly causing mild diseases. However, in vulnerable populations, such as newborns, infants, the elderly and immune-compromised individuals, these opportunistic pathogens can also affect the lower respiratory tract, causing a more severe disease (e.g., pneumonia). Respiratory viruses can also exacerbate asthma and lead to various types of respiratory distress syndromes. Furthermore, as they can adapt fast and cross the species barrier, some of these pathogens, like influenza A and SARS-CoV, have occasionally caused epidemics or pandemics, and were associated with more serious clinical diseases and even mortality. For a few decades now, data reported in the scientific literature has also demonstrated that several respiratory viruses have neuroinvasive capacities, since they can spread from the respiratory tract to the central nervous system (CNS). Viruses infecting human CNS cells could then cause different types of encephalopathy, including encephalitis, and long-term neurological diseases. Like other well-recognized neuroinvasive human viruses, respiratory viruses may damage the CNS as a result of misdirected host immune responses that could be associated with autoimmunity in susceptible individuals (virus-induced neuro-immunopathology) and/or viral replication, which directly causes damage to CNS cells (virus-induced neuropathology). The etiological agent of several neurological disorders remains unidentified. Opportunistic human respiratory pathogens could be associated with the triggering or the exacerbation of these disorders whose etiology remains poorly understood. Herein, we present a global portrait of some of the most prevalent or emerging human respiratory viruses that have been associated with possible pathogenic processes in CNS infection, with a special emphasis on human coronaviruses.

Construction of AAV-rat-IL4 and Evaluation of its Modulating Effect on Aβ (1-42)-Induced Proinflammatory Cytokines in Primary Microglia and the B92 Cell Line by Quantitative PCR Assay

BACKGROUND

Interleukin-4 (IL-4), as the most prominent anti-inflammatory cytokine, plays an important role in modulating microglial activation and inflammatory responses in Alzheimer's disease (AD), a chronic inflammatory disorder.

OBJECTIVES

The current study aimed to develop a new recombinant Adeno-associated viral (rAAV) vector that delivers IL-4 and then assess the counterbalancing effect of the new construct along with recombinant IL-4 (rIL-4) protein in in-vitro models of AD.

MATERIALS AND METHODS

The rAAV-IL4 was originally prepared and then employed along with rIL-4 protein to counter Amyloid β (1-42)-induced proinflammatory cytokines in a primary microglia cell culture and the B92 rat microglia continuous cell line, using relative Real-Time PCR assay.

RESULTS

Aβ (1-42) stimulated the production of the proinflammatory cytokines IL6, IL1β, TNFα, and IL18 in both the primary microglia cell culture and the B92 cell line. Both the rAAV-IL4 construct and the rIL-4 protein were found to inhibit production of the most important Aβ (1-42)-induced proinflammatory cytokine mRNAs in the two types of cells with different patterns.

CONCLUSIONS

It seems that the new construct can serve as an appropriate option in the modulation of Aβ-induced proinflammatory cytokine gene expression and microglia activation in patients affected by AD.

Human coronaviruses: viral and cellular factors involved in neuroinvasiveness and neuropathogenesis

•

Human coronavirus (HCoV) are naturally neuroinvasive in both mice and humans.

•

Both transneuronal and hematogenous route may allow virus invasion of the CNS.

•

Infection of neurons leads to excitotoxicity, neurodegeneration and cell-death.

•

HCoV are potentially associated with human neurological disorders.

Among the various respiratory viruses infecting human beings, coronaviruses are important pathogens, which usually infect the upper respiratory tract, where they are mainly associated with common colds. However, in more vulnerable populations, such as newborns, infants, the elderly and immune-compromised individuals, these opportunistic pathogens can also affect the lower respiratory tract, leading to pneumonia, exacerbations of asthma, and various types of respiratory distress syndrome. The respiratory involvement of human coronaviruses has been clearly established since the 1960s. Nevertheless, for almost three decades now, data reported in the scientific literature has also demonstrated that, like it was described for other human viruses, coronaviruses have neuroinvasive capacities since they can spread from the respiratory tract to the central nervous system (CNS). Once there, infection of CNS cells (neurotropism) could lead to human health problems, such as encephalitis and long-term neurological diseases. Neuroinvasive coronaviruses could damage the CNS as a result of misdirected host immune responses that could be associated with autoimmunity in susceptible individuals (virus-induced neuroimmunopathology) and/or viral replication, which directly induces damage to CNS cells (virus-induced neuropathology). Given all these properties, it has been suggested that these opportunistic human respiratory pathogens could be associated with the triggering or the exacerbation of neurologic diseases for which the etiology remains poorly understood. Herein, we present host and viral factors that participate in the regulation of the possible pathogenic processes associated with CNS infection by human coronaviruses and we try to decipher the intricate interplay between virus and host target cells in order to characterize their role in the virus life cycle as well as in the capacity of the cell to respond to viral invasion.

Neuroinvasive and neurotropic human respiratory coronaviruses: potential neurovirulent agents in humans

In humans, viral infections of the respiratory tract are a leading cause of morbidity and mortality worldwide. Several recognized respiratory viral agents have a neuroinvasive capacity since they can spread from the respiratory tract to the central nervous system (CNS). Once there, infection of CNS cells (neurotropism) could lead to human health problems, such as encephalitis and long-term neurological diseases. Among the various respiratory viruses, coronaviruses are important pathogens of humans and animals. Human Coronaviruses (HCoV) usually infect the upper respiratory tract, where they are mainly associated with common colds. However, in more vulnerable populations, such as newborns, infants, the elderly, and immune-compromised individuals, they can also affect the lower respiratory tract, leading to pneumonia, exacerbations of asthma, respiratory distress syndrome, or even severe acute respiratory syndrome (SARS). The respiratory involvement of HCoV has been clearly established since the 1960s. In addition, for almost three decades now, the scientific literature has also demonstrated that HCoV are neuroinvasive and neurotropic and could induce an overactivation of the immune system, in part by participating in the activation of autoreactive immune cells that could be associated with autoimmunity in susceptible individuals. Furthermore, it was shown that in the murine CNS, neurons are the main target of infection, which causes these essential cells to undergo degeneration and eventually die by some form of programmed cell death after virus infection. Moreover, it appears that the viral surface glycoprotein (S) represents an important factor in the neurodegenerative process. Given all these properties, it has been suggested that these recognized human respiratory pathogens could be associated with the triggering or the exacerbation of neurological diseases for which the etiology remains unknown or poorly understood.

Insight into the role of CRMP2 (collapsin response mediator protein 2) in T lymphocyte migration: the particular context of virus infection

Lymphocyte migration into the central nervous system is a critical step in the physiopathology of a variety of neurological diseases, including multiple sclerosis and virus-induced neuroinflammation. To better understand the molecular mechanisms involved in cells migration, we focused our studies on collapsin response mediator proteins (CRMPs), a group of phosphoproteins that mediate neural cell motility. There is now evidence that collapsin response mediator protein 2 (CRMP2) plays critical roles in the polarization (uropod formation) of T lymphocytes and their subsequent migration. CRMP2 was known to respond to semaphorin, ephrin and neurotrophin signaling in neurons. The link between the chemokine CXCL12, CRMP2 activity and cell migration has been demonstrated in T lymphocytes. These observations and comparisons of the activity of CRMPs in immune and non-immmune cells are summarized here. The ability of a human retrovirus to enhance lymphocyte migration through the modulation of CRMP2 activity is also discussed. In conclusion, viruses have the ability to manipulate the lymphocyte motility machinery, intensifying neural tissue invasion in infected patients.