COVID-19 and the Peripheral Nervous System. A 2-year review from the pandemic to the vaccine era

Tackling persistent neurological symptoms in patients following acute COVID-19 infection: an update of the literature

INTRODUCTION

The COVID-19 pandemic has taught myriad lessons and left several questions we are yet to comprehend. Initially, the scientific community was concerned with the management of acute disease and immunization. Once the peak of the pandemic receded, it became clear that a proportion of patients were far from fully recovered. Researchers started to recognize those persisting symptoms as a new entity termed 'Long COVID,' where neurological symptoms are evident and have a major impact on quality of life.

AREAS COVERED

The main purpose of this narrative review is to analyze and synthesize the current literature regarding Long COVID, its relation to the nervous system, and to explore the evidence on treatments for persistent neurological symptoms. The most common reported and observed neurologic manifestations include fatigue, cognitive impairment, pain, polyneuropathy, and neuropsychiatric disorders. A variety of pharmacologic and non-pharmacologic therapies have been evaluated and yielded mixed results. Many of them focused on immunomodulation and none currently have U.S. FDA approval.

EXPERT OPINION

Challenges remain in terms of clinical characterization and prognosis of Long COVID, besides understanding its pathophysiology. Standardization of biomarkers and diagnostic criteria will allow the use of common nomenclature and data elements in the design of future clinical studies.

What Is the Impact of the Novel Coronavirus and the Vaccination on Guillain-Barre Syndrome?

The COVID-19 pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has resulted in devastating medical and economic consequences worldwide over the past 3 years. As the pandemic enters a new stage, it is essential to consider the potential impact on rare diseases such as Guillain-Barre syndrome (GBS), which has been intimately associated with COVID-19 since the first COVID-19-related GBS case was reported in January 2020. There are notable differences between COVID-19-related GBS and GBS without COVID-19 in terms of diagnostic types and clinical manifestations. Furthermore, with the widespread administration of COVID-19 vaccines, there have been reports of GBS occurring shortly after vaccination, which requires close attention despite its rarity. This review also explores the vaccines associated with heightened GBS risks, offering insights that may guide vaccination policies and clinical practice. To provide a visual summary of these findings, we have included a graphical abstract.

Elimination of olfactory sensory neurons by zinc sulfate inoculation prevents SARS-CoV-2 infection of the brain in K18-hACE2 transgenic mice

Coronavirus disease-2019 (COVID-19), attributed to the severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2), has posed global health challenges since it first emerged in 2019, and its impact continues to persist. The neurotropic nature of SARS-CoV-2 remains undisclosed, though researchers are proposing hypotheses on how the virus is transmitted to the central nervous system. One of the prevailing hypotheses is that SARS-CoV-2 travels through the olfactory nerve system via the olfactory epithelium (OE). Using a K18-human angiotensin converting-enzyme 2 (hACE2) transgenic mouse model with impaired olfactory sensory neurons (OSNs) induced by zinc sulfate, we examined the role of the olfactory nerve in the brain invasion by SARS-CoV-2. Mice lacking OSNs exhibited reduced levels of viral transmission to the brain, leading to significantly improved outcomes following SARS-CoV-2 infection. Moreover, a positive correlation was observed between viral persistence in the OE and brain infection. These results indicate that early inhibition of the olfactory nerve pathway effectively prevents viral invasion of the brain in K18-hACE2 mice. Our study underscores the significance of the olfactory nerve pathway in the transmission of SARS-CoV-2 to the brain.

Peripheral Immune-Mediated Neuropathy Before and During the COVID-19 Pandemic: A Retrospective Cross-Sectional Study in a Referral Center

BACKGROUND

There are currently seven coronaviruses that can infect humans and the latest addition to these viruses is the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Infection by SARS-CoV-2 is known commonly as coronavirus disease 2019 (COVID-19). Aside from common manifestations of cough and fever, neurologic symptoms such as headache, disturbed consciousness, paresthesia, and seizures have also been seen. By identifying the incidence of peripheral immune-mediated neuropathies (PIMN), early prevention can be made.

METHODS

This cross-sectional retrospective analytic study reviewed the case records of patients examined at the Center for Neurodiagnostic and Therapeutic Services (CNS) of Metropolitan Medical Center from January 2018 to December 2021.

RESULTS

The period incidence of Guillain-Barré Syndrome (GBS) for the years 2018-2019 and 2020-2021 were 9.21% and 24.44%, respectively. The obtained p-value was 0.0226, which was lower than the set p-value of 0.05. Therefore, the period incidence of GBS for 2020-2021 was significantly higher when compared to that of 2018-2019.

CONCLUSION

There has been an increase in cases of GBS during the COVID-19 pandemic.

Lacrimal Neuralgia: A Case Report and Comprehensive Review of the Literature

PURPOSE OF REVIEW

Lacrimal neuralgia is a rare periorbital neuralgia. To date, only nine cases have been reported in the literature. Herein, we report a case and a comprehensive overview of the entity with a focus on the differential diagnosis of lacrimal neuralgia. Additionally, we propose putative diagnostic criteria for this rare neuralgia based on cases that have been reported.

RECENT FINDINGS

Among the ten cases of lacrimal neuralgia reported (including the one in this review), seven out of ten were idiopathic, and the other three were considered secondary. Most patients reported stabbing and shooting pain that was either paroxysmal or continuous. The most effective therapy was nerve block for seven patients and pregabalin for three patients. The most important clues to differentiate lacrimal neuralgia from other causes of periorbital pain include pain topography and pain with features suggestive of neuralgia. The core feature of lacrimal neuralgia is neuralgic pain located in the area supplied by the lacrimal nerve, and the etiology could be primary or secondary. Responsiveness to anesthetic blockade might better serve as a confirmational, rather than mandatory, criterion for diagnosis.

Post-SARS-CoV-2 infection and post-vaccine-related neurological complications share clinical features and the same positivity to anti-ACE2 antibodies

Introduction

A potential overlap in symptoms between post-acute COVID-19 syndrome and post-COVID-19 vaccination syndrome has been noted. We report a paired description of patients presenting with similar manifestations involving the central (CNS) or peripheral nervous system (PNS) following SARS-CoV-2 infection or vaccination, suggesting that both may have triggered similar immune-mediated neurological disorders in the presence of anti-idiotype antibodies directed against the ACE2 protein.

Patients and methods

Four patients exhibited overlapping neurological manifestations following SARS-CoV-2 infection or vaccination: radiculitis, Guillain-Barré syndrome, and MRI-negative myelitis, respectively, sharing positivity for anti-ACE2 antibodies. Autoantibodies against AQP-4, MOG, GlyR, GAD, and amphiphysin, onconeural antibodies for CNS syndromes, and anti-ganglioside antibodies for PNS syndromes tested negative in all patients.

Discussion

Anti-idiotype antibodies against ACE2 have been detected in patients who recovered from COVID-19 infection, and it has been hypothesized that such antibodies may mediate adverse events following SARS-CoV-2 infection or vaccination, resulting in the activation of the immune system against cells expressing ACE2, such as neurons. Our data reveal clinically overlapping syndromes triggered by SARS-CoV-2 infection or vaccination, sharing positivity for anti-ACE2 antibodies. Their presence, in the absence of other classic autoimmune markers of CNS or PNS involvement, suggests that they might play an active role in the context of an aberrant immune response.

Conclusion

Anti-idiotype antibodies directed against ACE2 may be triggered by both SARS-CoV-2 infection and vaccination, possibly contributing to neurological autoimmune manifestations. Their pathogenic role, however, remains to be demonstrated in large-scale, more structured studies.

COVID-19 and menstrual-related disturbances: a Spanish retrospective observational study in formerly menstruating women

Introduction

Four years after the start of the pandemic, there is limited evidence on the impact of COVID-19 on the women's health regardless of their reproductive status.

Objective

The aim was to analyze the prevalence and associated factors of menstrual-related disturbances in formerly menstruating women following SARS-CoV-2 infection.

Study design

A retrospective observational study of adult women in Spain was conducted during the month of December 2021 using an online survey (N = 17,512). The present analysis includes a subpopulation of SARS-CoV-2-infected and formerly menstruating women (n = 72). The collected data included general characteristics, medical history, and specific information on COVID-19. Chi-square and Mann-Whitney U-tests were performed. Bivariate logistic regression analysis was then performed to investigate possible associations between the occurrence of menstrual-related disturbances after SARS-CoV-2 infection.

Results

38.8% of participants experienced menstrual-related disturbances following COVID-19. Among these, unexpected vaginal bleeding (20.8%) was the most common event, followed by spotting (11.1%) ( Table 1). Other reported changes were in the length (shorter = 12.5%) and flow (heavier = 30.3%) of menstrual bleeding in comparison to their previous experience. Regression analysis revealed that being a perimenopausal woman [adjusted odds ratio (AOR) 4.721, CI 95%, 1.022-21.796, p = 0.047] and having a previous diagnosis of menorrhagia (AOR 5.824 CI 95%, 1.521-22.310, p = 0.010) were factors associated with the event.

Conclusion

These findings could help health professionals provide their patients with up-to-date scientific information to empower them to actively manage their reproductive health, especially in societies where menstrual health is still taboo.

Journey of Guillain Barre syndrome from the pre-pandemic era to the pandemic era: A 4-year retrospective study

Aims

To study demographic and clinical profiles of Guillain Barre syndrome (GBS) in the pre-pandemic and coronavirus disease 2019 (COVID-19) pandemic era and to compare the GBS incidence, severity, and its outcome in the pre-pandemic and pandemic eras.

Methodology

This is a 4-year retrospective study done in a tertiary care hospital in Delhi, India, between March 2018 and March 2022. Patients were divided into the pre-pandemic era and pandemic era (2 years before and 2 years after March 2020).

Results

The number of patients (N) was 25 in the pandemic/vaccine era, while N = 49 in the pre-pandemic era. The mean duration of hospitalization was significantly higher (P = 0.03) during the pandemic era (10.68 ± 6.67 days) compared to the pre-pandemic era (7.59 ± 3.55 days). There was no statistical difference in age (P = 0.56), gender (P = 0.70), GBS variants (P = 0.40), clinical spectrum, antecedent infection (P = 0.91), Hughes Disability Score on admission and discharge (P = 0.93 and P = 0.52, respectively), respiratory involvement requiring a ventilator (P = 0.19), and mortality (P = 0.26) in both the eras.

Conclusion

Our study showed no association of the incidence of GBS with the ongoing COVID-19 pandemic. The mean hospitalization days were significantly increased during COVID-19 in view of associated respiratory involvement. The commonly held hypothesis of the increase in GBS cases during the pandemic/vaccine era has not been observed in our study.

Incidence and management of the main serious adverse events reported after COVID-19 vaccination

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2n first appeared in Wuhan, China in 2019. Soon after, it was declared a pandemic by the World Health Organization. The health crisis imposed by a new virus and its rapid spread worldwide prompted the fast development of vaccines. For the first time in human history, two vaccines based on recombinant genetic material technology were approved for human use. These mRNA vaccines were applied in massive immunization programs around the world, followed by other vaccines based on more traditional approaches. Even though all vaccines were tested in clinical trials prior to their general administration, serious adverse events, usually of very low incidence, were mostly identified after application of millions of doses. Establishing a direct correlation (the cause-effect paradigm) between vaccination and the appearance of adverse effects has proven challenging. This review focuses on the main adverse effects observed after vaccination, including anaphylaxis, myocarditis, vaccine-induced thrombotic thrombocytopenia, Guillain-Barré syndrome, and transverse myelitis reported in the context of COVID-19 vaccination. We highlight the symptoms, laboratory tests required for an adequate diagnosis, and briefly outline the recommended treatments for these adverse effects. The aim of this work is to increase awareness among healthcare personnel about the serious adverse events that may arise post-vaccination. Regardless of the ongoing discussion about the safety of COVID-19 vaccination, these adverse effects must be identified promptly and treated effectively to reduce the risk of complications.

Optic Neuritis and Cranial Neuropathies Diagnosis Rates before Coronavirus Disease 2019, in the Initial Pandemic Phase, and Post-Vaccine Introduction

PURPOSE

To compare rates of diagnosis of neuro-ophthalmic conditions across the Coronavirus Disease 2019 (COVID-19) pandemic with pre-pandemic levels.

DESIGN

Multicenter, retrospective, observational study.

PARTICIPANTS

Patients seen for eye care between March 11, 2019, and December 31, 2021.

METHODS

A multicenter electronic health record database, Sight Outcomes Research Collaborative (SOURCE), was queried for new diagnoses of neuro-ophthalmic conditions (cranial nerve [CN] III, IV, VI, and VII palsy; diplopia; and optic neuritis) and new diagnoses of other ophthalmic conditions from January 1, 2016, to December 31, 2021. Data were divided into 3 periods (pre-COVID, pre-COVID vaccine, and after introduction of COVID vaccine), with a 3-year look-back period. Logistic regressions were used to compare diagnosis rates across periods. Two-sample z-test was used to compare the log odds ratio (OR) of the diagnosis in each period with emergent ocular conditions: retinal detachment (RD) and acute angle-closure glaucoma (AACG).

MAIN OUTCOME MEASURES

Diagnosis rate of neuro-ophthalmic conditions in each study period.

RESULTS

A total of 323 261 unique patients (median age 59 years [interquartile range, 43-70], 58% female, 68% White) across 5 academic centers were included, with 180 009 patients seen in the pre-COVID period, 149 835 patients seen in the pre-COVID vaccine period, and 164 778 patients seen in the COVID vaccine period. Diagnosis rates of CN VII palsy, diplopia, glaucoma, and cataract decreased from the pre-COVID period to the pre-vaccine period. However, the optic neuritis diagnoses increased, in contrast to a decrease in RD diagnoses (P = 0.021). By comparing the diagnosis rates before and after widespread vaccination, all eye conditions evaluated were diagnosed at higher rates in the COVID vaccination period compared with pre-COVID and pre-vaccine periods. The log OR of neuro-ophthalmic diagnosis rates across every period comparison were largely similar to emergency conditions (RD and AACG, P > 0.05). However, the log OR of cataract and glaucoma diagnoses were different to RD or AACG (P < 0.05) in each period comparison.

CONCLUSIONS

Neuro-ophthalmic diagnoses had a similar reduction in diagnosis rates as emergent eye conditions in the first part of the pandemic, except optic neuritis. After widespread COVID-19 vaccination, all ophthalmic diagnosis rates increased compared with pre-pandemic rates, and the increase in neuro-ophthalmic diagnosis rates did not exceed the increase in RD and AACG diagnosis rates.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Parsonage-Turner Syndrome and Hereditary Brachial Plexus Neuropathy

Parsonage-Turner syndrome and hereditary brachial plexus neuropathy (HBPN) present with indistinguishable attacks of rapid-onset severe shoulder and arm pain, disabling weakness, and early muscle atrophy. Their combined incidence ranges from 3 to 100 in 100,000 persons per year. Dominant mutations of SEPT9 are the only known mutations responsible for HBPN. Parsonage and Turner termed the disorder "brachial neuralgic amyotrophy," highlighting neuropathic pain and muscle atrophy. Modern electrodiagnostic and imaging testing assists the diagnosis in distinction from mimicking disorders. Shoulder and upper limb nerves outside the brachial plexus are commonly affected including the phrenic nerve where diaphragm ultrasound improves diagnosis. Magnetic resonance imaging can show multifocal T2 nerve and muscle hyperintensities with nerve hourglass swellings and constrictions identifiable also by ultrasound. An inflammatory immune component is suggested by nerve biopsies and associated infectious, immunization, trauma, surgery, and childbirth triggers. High-dose pulsed steroids assist initial pain control; however, weakness and subsequent pain are not clearly responsive to steroids and instead benefit from time, physical therapy, and non-narcotic pain medications. Recurrent attacks in HBPN are common and prophylactic steroids or intravenous immunoglobulin may reduce surgical- or childbirth-induced attacks. Rehabilitation focusing on restoring functional scapular mechanics, energy conservation, contracture prevention, and pain management are critical. Lifetime residual pain and weakness are rare with most making dramatic functional recovery. Tendon transfers can be used when recovery does not occur after 18 months. Early neurolysis and nerve grafts are controversial. This review provides an update including new diagnostic tools, new associations, and new interventions crossing multiple medical disciplines.

Persisting Shadows: Unraveling the Impact of Long COVID-19 on Respiratory, Cardiovascular, and Nervous Systems

The coronavirus disease 2019 (COVID-19), instigated by the zoonotic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), rapidly transformed from an outbreak in Wuhan, China, into a widespread global pandemic. A significant post-infection condition, known as 'long- COVID-19' (or simply 'long- COVID'), emerges in a substantial subset of patients, manifesting with a constellation of over 200 reported symptoms that span multiple organ systems. This condition, also known as 'post-acute sequelae of SARS-CoV-2 infection' (PASC), presents a perplexing clinical picture with far-reaching implications, often persisting long after the acute phase. While initial research focused on the immediate pulmonary impact of the virus, the recognition of COVID-19 as a multiorgan disruptor has unveiled a gamut of protracted and severe health issues. This review summarizes the primary effects of long COVID on the respiratory, cardiovascular, and nervous systems. It also delves into the mechanisms underlying these impacts and underscores the critical need for a comprehensive understanding of long COVID's pathogenesis.

Neuromuscular diseases associated with COVID-19 vaccines: a systematic review and pooled analysis of 258 patients

BACKGROUND

Neuromuscular diseases (NMD) emerged as one of the main side effects of the COVID-19 vaccination. We pooled and summarized the evidence on the clinical features and outcomes of NMD associated with COVID-19 vaccination.

METHODS

We comprehensively searched three databases, Medline, Embase, and Scopus, using the key terms covering "Neuromuscular disease" AND "COVID-19 vaccine", and pooled the individual patient data extracted from the included studies.

RESULTS

A total of 258 NMD cases following COVID-19 have been reported globally, of which 171 cases were Guillain-Barré syndrome (GBS), 40 Parsonage-Turner syndrome (PTS), 22 Myasthenia Gravis (MG), 19 facial nerve palsy (FNP), 5 single fiber neuropathy, and 1 Tolosa-Hunt syndrome. All (100%) SFN patients and 58% of FNP patients were female; in the remaining NMDs, patients were predominantly male, including MG (82%), GBS (63%), and PTS (62.5%). The median time from vaccine to symptom was less than 2 weeks in all groups. Symptoms mainly appeared following the first dose of vector vaccine, but there was no specific pattern for mRNA-based.

CONCLUSION

COVID-19 vaccines might induce some NMDs, mainly in adults. The age distribution and gender characteristics of affected patients may differ based on the NMD type. About two-thirds of the cases probably occur less than 2 weeks after vaccination.

Chronic inflammatory demyelinating polyneuropathy after SARS-CoV2 vaccination: update of the literature and patient characterization

Since the beginning of worldwide vaccination against COVID-19 disease, some reports have revealed a possible relationship between SARS CoV2 vaccination and chronic inflammatory demyelinating polyneuropathy (CIDP). We reviewed the available evidences regarding this topic, adding three new cases to those reported so far, with the purpose to outline the characteristics of these post-vaccinal CIDP. Seventeen subjects were studied. A total of 70.6% of CIDP cases were related to viral vector vaccines, most occurring after the administration of the first dose. CIDPs that occurred after the second dose (17%) were temporally associated with mRNA vaccines. The clinical course and electrophysiology of all patients met the criteria for acute-subacute CIDP (A-CIDP). Administration of the viral vector vaccine was significantly correlated with a higher probability of having cranial nerve impairment (p = 0.004). The electrophysiological phenotype, laboratory and imaging data, and first-line therapies were substantially similar to those of the classical CIDP. The take-home message of the present paper is that the SARS CoV2 vaccine, especially the AstraZeneca vaccine, may be associated with inflammatory neuropathies with acute onset, often indistinguishable from Guillain-Barré syndrome (GBS). Hence, the importance of tracked prospectively patients with GBS occurred post-SARS-CoV2 vaccine. Distinguishing GBS from A-CIDP is crucial because treatment strategies and long-term prognosis are different.

Subclinical finding in the perception of tactile sensation involvement after SARS-CoV2 infection: comparison with healthy controls using Semmes-Weinstein monofilament testing

Background

Post-acute COVID-19 syndrome patients complain of sensory alterations, mainly positive symptoms such as paresthesia or neuropathic pain but also decreased tactile sensation. Using the Semmes-Weinstein monofilament test (SWMT), our study aims to confront recently infected SARS-CoV2 subjects with a control group.

Methods

This is a cross-sectional, single-centric study. We performed the SWMT (North Coast Medical Inc.) on 30 patients with previous SARS-CoV2 infection (COVID group) and 46 controls (control group). These patients did not present comorbidities or sensory impairment and did not take any medications. The control group tested negative for SARS-CoV2 infection since the COVID-19 pandemic; the COVID group was examined for this study after the resolution of the infection. We tested the threshold of tactile sensation of the tips of the thumb, index, and little finger of each hand, one hand at a time; the dorsum and the hypothenar regions were also tested.

Results

Both groups presented the perception of tactile sensation within the reference value. Despite this result, subclinical changes suggestive of the involvement in peripheral sensory nerve function have been identified in the tested sites in the COVID group compared to the control group. The overall mean target force (grams) was higher in the COVID group than in the control group: 27 (7) vs. 19 (10) mg, p < 0.001.

Conclusion

Controls and the COVID group infection had normal tactile sensation thresholds. However, the COVID group presented a higher threshold than the control group, suggesting a possible subclinical perception of tactile sensation involvement of A-beta nerve fibers.

Tendon Transfer to Treat Radial Nerve Palsy Following COVID-19 Infection

Multiple manifestations have been associated with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Among them are mononeuritis multiplex (MNM) and other neurological complications, whose connection to coronavirus disease 2019 (COVID-19) is still unclear. One of the most common sites of nerve injury is the radial nerve, which can be treated with both nerve or tendon transfer. In this case report, a patient who was afflicted with severe COVID-19 infection and developed mono neuritis multiplex after prolonged mechanical ventilation with radial nerve palsy was treated with multiple tendon transfers. This is a way to use an established mechanism of resolving the manifestations of radial nerve palsy to aid in the recovery of COVID-19-related mononeuritis multiplex.

Infectious Neuropathies

OBJECTIVE

This article discusses the clinical manifestations and management of infectious peripheral neuropathies.

LATEST DEVELOPMENTS

Several infectious etiologies of peripheral neuropathy are well-recognized and their treatments are firmly established. The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is associated with several central and peripheral nervous system manifestations, including peripheral neuropathies. Additionally, some COVID-19 vaccines have been associated with Guillain-Barré syndrome. These disorders are an active area of surveillance and research. Recent evidence-based guidelines have provided updated recommendations for the diagnosis and treatment of Lyme disease.

ESSENTIAL POINTS

Infectious agents of many types (primarily bacteria and viruses) can affect the peripheral nerves, resulting in various clinical syndromes such as mononeuropathy or mononeuropathy multiplex, distal symmetric polyneuropathy, radiculopathy, inflammatory demyelinating polyradiculoneuropathy, and motor neuronopathy. Knowledge of these infections and the spectrum of peripheral nervous system disorders associated with them is essential because many have curative treatments. Furthermore, understanding the neuropathic presentations of these disorders may assist in diagnosing the underlying infection.

Guillain-Barré Syndrome

OBJECTIVE

This article summarizes the clinical features, diagnostic criteria, differential diagnosis, pathogenesis, and prognosis of Guillain-Barré syndrome (GBS), with insights into the current and future diagnostic and therapeutic interventions for this neuromuscular syndrome.

LATEST DEVELOPMENTS

GBS is an acute, inflammatory, immune-mediated polyradiculoneuropathy that encompasses many clinical variants and divergent pathogenic mechanisms that lead to axonal, demyelinating, or mixed findings on electrodiagnostic studies. The type of antecedent infection, the development of pathogenic cross-reactive antibodies via molecular mimicry, and the location of the target gangliosides affect the subtype and severity of the illness. The data from the International GBS Outcome Study have highlighted regional variances, provided new and internationally validated prognosis tools that are beneficial for counseling, and introduced a platform for discussion of GBS-related open questions. New research has been undertaken, including research on novel diagnostic and therapeutic biomarkers, which may lead to new therapies.

ESSENTIAL POINTS

GBS is among the most frequent life-threatening neuromuscular emergencies in the world. At least 20% of patients with GBS have a poor prognosis and significant residual deficits despite receiving available treatments. Research is ongoing to further understand the pathogenesis of the disorder, find new biomarkers, and develop more effective and specific treatments.

Persistent post-COVID-19 neuromuscular symptoms

Neuromuscular symptoms may develop or persist after resolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Besides residual sensorimotor symptoms associated with acute neuromuscular complications of coronavirus disease-2019 (COVID-19), such as Guillain-Barré syndrome, critical illness neuromyopathy, and rhabdomyolysis, patients may report persistent autonomic symptoms, sensory symptoms, and muscle symptoms in the absence of these acute complications, including palpitations, orthostatic dizziness and intolerance, paresthesia, myalgia, and fatigue. These symptoms may be associated with long COVID, also known as post-COVID-19 conditions or postacute sequelae of SARS-CoV-2 infection, which may significantly impact quality of life. Managing these symptoms represents a challenge for health-care providers. Recent advances have identified small-fiber neuropathy as a potential etiology that may underlie autonomic dysfunction and paresthesia in some long COVID patients. The pathogenic mechanisms underlying myalgia and fatigue remain elusive and need to be investigated. Herein we review the current state of knowledge regarding the evaluation and management of patients with persistent post-COVID-19 neuromuscular symptoms.

Neurological manifestations of SARS-CoV-2: complexity, mechanism and associated disorders

BACKGROUND

Coronaviruses such as Severe Acute Respiratory Syndrome coronavirus (SARS), Middle Eastern Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) are associated with critical illnesses, including severe respiratory disorders. SARS-CoV-2 is the causative agent of the deadly COVID-19 illness, which has spread globally as a pandemic. SARS-CoV-2 may enter the human body through olfactory lobes and interact with the angiotensin-converting enzyme2 (ACE2) receptor, further facilitating cell binding and entry into the cells. Reports have shown that the virus can pass through the blood-brain barrier (BBB) and enter the central nervous system (CNS), resulting in various disorders. Cell entry by SARS-CoV-2 largely relies on TMPRSS2 and cathepsin L, which activate S protein. TMPRSS2 is found on the cell surface of respiratory, gastrointestinal and urogenital epithelium, while cathepsin-L is a part of endosomes.

AIM

The current review aims to provide information on how SARS-CoV-2 infection affects brain function.. Furthermore, CNS disorders associated with SARS-CoV-2 infection, including ischemic stroke, cerebral venous thrombosis, Guillain-Barré syndrome, multiple sclerosis, meningitis, and encephalitis, are discussed. The many probable mechanisms and paths involved in developing cerebrovascular problems in COVID patients are thoroughly detailed.

MAIN BODY

There have been reports that the SARS-CoV-2 virus can cross the blood-brain barrier (BBB) and enter the central nervous system (CNS), where it could cause a various illnesses. Patients suffering from COVID-19 experience a range of neurological complications, including sleep disorders, viral encephalitis, headaches, dysgeusia, and cognitive impairment. The presence of SARS-CoV-2 in the cerebrospinal fluid (CSF) of COVID-19 patients has been reported. Health experts also reported its presence in cortical neurons and human brain organoids. The possible mechanism of virus infiltration into the brain can be neurotropic, direct infiltration and cytokine storm-based pathways. The olfactory lobes could also be the primary pathway for the entrance of SARS-CoV-2 into the brain.

CONCLUSIONS

SARS-CoV-2 can lead to neurological complications, such as cerebrovascular manifestations, motor movement complications, and cognitive decline. COVID-19 infection can result in cerebrovascular symptoms and diseases, such as strokes and thrombosis. The virus can affect the neural system, disrupt cognitive function and cause neurological disorders. To combat the epidemic, it is crucial to repurpose drugs currently in use quickly and develop novel therapeutics.

COVID-19: a modern trigger for Guillain-Barre syndrome, myasthenia gravis, and small fiber neuropathy

COVID-19 infection has had a profound impact on society. During the initial phase of the pandemic, there were several suggestions that COVID-19 may lead to acute and protracted neurologic sequelae. For example, peripheral neuropathies exhibited distinctive features as compared to those observed in critical care illness. The peripheral nervous system, lacking the protection afforded by the blood-brain barrier, has been a particular site of sequelae and complications subsequent to COVID-19 infection, including Guillain-Barre syndrome, myasthenia gravis, and small fiber neuropathy. We will discuss these disorders in terms of their clinical manifestations, diagnosis, and treatment as well as the pathophysiology in relation to COVID-19.

Pathophysiology, diagnosis, and management of neuroinflammation in covid-19

Although neurological complications of SARS-CoV-2 infection are relatively rare, their potential long term morbidity and mortality have a significant impact, given the large numbers of infected patients. Covid-19 is now in the differential diagnosis of a number of common neurological syndromes including encephalopathy, encephalitis, acute demyelinating encephalomyelitis, stroke, and Guillain-Barré syndrome. Physicians should be aware of the pathophysiology underlying these presentations to diagnose and treat patients rapidly and appropriately. Although good evidence has been found for neurovirulence, the neuroinvasive and neurotropic potential of SARS-CoV-2 is limited. The pathophysiology of most complications is immune mediated and vascular, or both. A significant proportion of patients have developed long covid, which can include neuropsychiatric presentations. The mechanisms of long covid remain unclear. The longer term consequences of infection with covid-19 on the brain, particularly in terms of neurodegeneration, will only become apparent with time and long term follow-up.

COVID-19 in the nervous system: physiopathology and neurological manifestations

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a viral infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although respiratory manifestations have received greater visibility during the pandemic caused by this virus, numerous neurological complaints related to coronavirus 2 infection have been documented in several countries. These records suggest that this pathogen presents neurotropism, and it can cause different neurological conditions of varying intensity.

OBJECTIVE

To investigate the ability of coronavirus 2 to invade the central nervous system (CNS) and its neurological clinical outcomes.

METHODS

The present study consists in a comprehensive literature review of the records available in the PubMed, SciELO, and Google Scholar databases. The descriptors COVID-19, brain and physiopathology, associated with the Boolean operator AND, were used in the search. Regarding the inclusion and exclusion criteria, we selected the papers published since 2020 with the highest number of citations.

RESULTS

We selected 41 articles, most of them in English. The main clinical manifestation associated with COVID-19 patients was headache, but cases of anosmia, hyposmia, Guillain-Barré syndrome, and encephalopathies were also described with considerable frequency.

CONCLUSION

Coronavirus-2 presents neurotropism, and it can reach the CNS by hematogenous dissemination and by direct infection of the nerve endings. It causes brain injuries through several mechanisms, such as cytokine storm, microglial activation, and an increase in thrombotic factors.

Long COVID, the Brain, Nerves, and Cognitive Function

SARS-CoV-2, a single-stranded RNA coronavirus, causes an illness known as coronavirus disease 2019 (COVID-19). Long-term complications are an increasing issue in patients who have been infected with COVID-19 and may be a result of viral-associated systemic and central nervous system inflammation or may arise from a virus-induced hypercoagulable state. COVID-19 may incite changes in brain function with a wide range of lingering symptoms. Patients often experience fatigue and may note brain fog, sensorimotor symptoms, and sleep disturbances. Prolonged neurological and neuropsychiatric symptoms are prevalent and can interfere substantially in everyday life, leading to a massive public health concern. The mechanistic pathways by which SARS-CoV-2 infection causes neurological sequelae are an important subject of ongoing research. Inflammation- induced blood-brain barrier permeability or viral neuro-invasion and direct nerve damage may be involved. Though the mechanisms are uncertain, the resulting symptoms have been documented from numerous patient reports and studies. This review examines the constellation and spectrum of nervous system symptoms seen in long COVID and incorporates information on the prevalence of these symptoms, contributing factors, and typical course. Although treatment options are generally lacking, potential therapeutic approaches for alleviating symptoms and improving quality of life are explored.

The added value of lung perfusion scintigraphy semiquantitative measures in post-COVID patients with persistent dyspnea without pulmonary embolism

BACKGROUND

Persistent dyspnea is frequent in post-COVID patients, even in the absence of pulmonary embolism (PE). In this scenario, the role of lung perfusion scintigraphy is unclear. The present study correlated scintigraphy-based semiquantitative perfusion parameters with chest high-resolution computed tomography (hrCT) volumetric indexes and clinical data in post-COVID patients with persistent dyspnea.

RESEARCH DESIGN AND METHODS

Sixty patients (30 post-COVID and 30 not previously affected by COVID-19) with persistent dyspnea submitted to lung perfusion scintigraphy and hrCT were retrospectively recruited. Perfusion rates of the pulmonary fields and hrCT-based normalized inflated, emphysematous, infiltrated, collapsed, and vascular lung volumes were calculated. Inflammatory and coagulation biomarkers were collected. PE at imaging was an exclusion criterion.

RESULTS

Compared to controls, reduced perfusion rates of the lower pulmonary fields and higher perfusion rates of the middle ones were observed in post-COVID patients, while hrCT findings were superimposable between the two groups. Perfusion rates of lower pulmonary fields were significantly associated only with abnormal lung volumes at hrCT.

CONCLUSIONS

In post-COVID dyspnea without PE, lung perfusion scintigraphy may reveal a pulmonary involvement not detectable by hrCT. Post-COVID patients may show decreased perfusion rates of lower pulmonary fields in the presence of normal vascular density and markers of inflammation/coagulation.

Post-COVID-19 Vaccination CNS Magnetic Resonance Imaging Findings: A Systematic Review

Objective

This systematic review aims to synthesize and analyze the available literature on central nervous system (CNS) magnetic resonance imaging (MRI) findings in individuals who have received COVID-19 vaccinations. Our objective is to enhance understanding of potential neurological side effects, inform clinical practice, and guide future research on the neurological implications of COVID-19 vaccination.

Methods

In this systematic review, we conducted a comprehensive search in PubMed, Scopus, and Web of Science from January 2020 to April 2023, using terms related to COVID-19 vaccination and CNS MRI findings. We evaluated the quality of the study, extracted relevant data, and included 89 eligible studies that covered various vaccines, demographics of patients, symptoms, and MRI findings to provide a thorough understanding of SARS-CoV-2 vaccination-related CNS problems.

Results

We investigated CNS MRI findings following COVID-19 vaccination across various vaccine types. Common diseases associated with post-vaccination CNS MRI findings included cerebral venous sinus thrombosis (CVST), vaccine-induced immune thrombotic thrombocytopenia (VITT), acute disseminated encephalomyelitis (ADEM), acute myelitis, autoimmune encephalitis (AE), and others. Patients presented with diverse onset symptoms and neurological manifestations. Abnormalities identified in CNS MRI findings included white matter (WM) hyperintensity. Our analysis offers a comprehensive overview of the current literature on post-vaccination CNS MRI findings. Discussion. We highlight a range of post-COVID-19 vaccination CNS MRI findings, including CVST, with a higher incidence in individuals receiving the ChAdOx1 (AstraZeneca) vaccine. Other notable observations include cases of ADEM, myelitis or transverse myelitis (TM), Guillain-Barré syndrome (GBS), and acute encephalopathy following COVID-19 vaccination. The incidence of these neurological complications is extremely rare, and the benefits of vaccination outweigh the risks. The reviewed studies were primarily case reports or case series, and thus large-scale epidemiological studies and controlled clinical trials are needed to better understand the underlying mechanisms and risk factors associated with these neurological complications following COVID-19 vaccination.

SARS-CoV-2 and the nervous system: current perspectives

SARS-CoV-2 infection frequently causes neurological impairment in both adults and children. Recent publications have described significant aspects of the viral pathophysiology associated with neurological dysfunction. In theory, neurological manifestations following SARS-CoV-2 infection may be caused directly by the effects of the virus infecting the brain or indirectly by the local and systemic immune responses against the virus. Neurological manifestations can occur during the acute phase as well as in the post-acute phase of the infection. In this review, we discuss recent literature describing the association of nervous system disorders with COVID-19.

Incidence and clinical characteristics of adverse neurological events and stroke-like syndrome associated with immune stress-related response after COVID-19 vaccination in 2021 from Thailand

OBJECTIVES

AEFIs (adverse events following immunizations), especially ISRR ( immune stress related response) which can cause stroke-like symptoms may affect the vaccine roll-out campaign to prevent the coronavirus 2019 outbreak.

METHODS

This study aimed to describe the incidence and clinical characteristics of neurological AEFIs and stroke-like symptoms associated with ISRR after COVID-19 vaccination. Characteristics of ISRR were compared to minor ischemic stroke patients during the same period of the study. During March to September 2021, we retrospectively collected data of participants aged ≥ 18 years who received COVID-19 vaccine and developed AEFIs from Thammasat university vaccination center (TUVC). Data of neurological AEFIs patients and minor ischemic stroke patients were collected from hospital electronic medical record system.

RESULTS

COVID-19 vaccine were administered at TUVC for 245,799 doses. AEFIs were reported in 129,652 instances (52.6%). ChADOx-1 nCoV-19 viral vector vaccine has the most frequent occurrence of AEFIs (58.0%), and neurological AEFIs (12.6%). 83% of neurological AEFI was headache. Most were mild and did not need medical attention. Of 119 patients who received COVID-19 vaccine from anywhere with neurological AEFIs and presented to TUH, ISRR was diagnosed in 107 patients (89.9%) and all patients who has follow-up data (30.8%) showed clinical improvement. In comparison with minor ischemic stroke (116 patients), ISRR patients had significantly less ataxia, facial weakness, weakness of arm/leg and speech disturbances (P < 0.001).

CONCLUSION

The incidence of neurological AEFIs after COVID-19 vaccination was higher among recipients of ChAdOx-1 nCoV-19 vaccine (12.6%) than inactivated vaccine (6.2%) and mRNA vaccine (7.5%). However, most neurological AEFIs were ISRR, had mild severity and resolved within 30 days. Stroke-like symptoms occurred less frequently than patients with minor ischemic stroke.

Neuromuscular Disorders Associated With COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has had an enormous impact on practically every aspect of daily life, and those with neuromuscular disorders have certainly not been spared. The effects of COVID-19 infection are far-reaching, going well beyond respiratory symptoms alone. From simple myalgias to debilitating critical illness neuromyopathies, we continue to learn and catalog the diverse pathologies presented by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as it relates to the neuromuscular system. Complications have been documented both as a direct result of primary infection but also in those with pre-existing neuromuscular disorders from myasthenia gravis to devastating critical illness neuromyopathies. In this review, we will discuss the relationship between COVID-19 infection and critical illness neuromyopathy, peripheral nerve palsies, myalgias, positional compressive neuropathy, myasthenia gravis, and Guillain-Barré syndrome.

Is there a causal nexus between COVID-19 infection, COVID-19 vaccination, and Guillain-Barré syndrome?

Guillain-Barré syndrome (GBS) is an immune-mediated inflammatory polyradiculoneuropathy, which commonly leads to a very high level of neurological disability. Especially, after the global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the causation between GBS and SARS-CoV-2 infection and the coronavirus disease 2019 (COVID-19) vaccination have aroused widespread concern. In the review, we analyzed the impacts of SARS-CoV-2 infection and COVID-19 vaccination on GBS globally, aiming to further understand the characteristics of GBS associated with COVID-19. Based on the electrophysiological data, patients suffering from GBS related to COVID-19 manifested as an acute inflammatory demyelinating polyneuropathy (AIDP). Moreover, we summarized the current findings, which may evidence GBS linking to SARS-CoV-2 infection and COVID-19 vaccination, and discussed the underlying mechanisms whether and how the SARS-CoV-2 virus and COVID-19 vaccination can induce GBS and its variants.

Knowledge mapping of global trends for myasthenia gravis development: A bibliometrics analysis

Background

Myasthenia gravis (MG) is an autoimmune disease with acquired neuromuscular junction transmission disorders. In the last two decades, various pathogenesis, application of immunosuppressive agents, and targeted immunotherapy have been significant events. However, extracting the most critical information from complex events is very difficult to guide clinical work. Therefore, we used bibliometrics to summarize and look forward.

Methods

Science Citation Index Expanded (SCI-E) from the Web of Science Core Collection (WoSCC) database was identified as a source of material for obtaining MG-related articles. Scimago Graphica, CiteSpace, VOSviewer, and bibliometrix were utilized for bibliometric analysis. Knowledge network graphs were constructed and visualized; countries, institutions, authors, journals, references, and keywords were evaluated. In addition, GraphPad Prism and Microsoft Excel 365 were applied for statistical analysis.

Results

As of October 25, 2022, 9,970 original MG-related articles were used for the bibliometric analysis; the cumulative number of citations to these articles was 236,987, with an H-index of 201. The United States ranked first in terms of the number of publications (2,877) and H-index (134). Oxford has the highest H-index (67), and Udice French Research University has the highest number of publications (319). The author with the highest average number of citations (66.19), publications (151), and H-index (53) was Vincent A. 28 articles have remained in an explosive period of citations. The final screening yielded predictive keywords related to clinical trials and COVID-19.

Conclusion

We conducted a bibliometric analysis of 9,970 original MG-related articles published between 1966 and 2022. Ultimately, we found that future MG research hotspots include two major parts: (1) studies directly related to MG disease itself: clinical trials of various targeted biological agents; the relationship between biomarkers and therapeutic decisions, pathogenesis and outcome events, ultimately serving individualized management or precision therapy; (2) studies related to MG and COVID-19: different variants of COVID-19 (e.g., Omicron) on MG adverse outcome events; assessment of the safety of different COVID-19 vaccines for different subtypes of MG.

[Neurointensive care medicine and COVID-19]

This review article summarizes important findings on the interfaces between the coronavirus disease 2019 (COVID-19) pandemic and neurology with an emphasis of the implications for neurointensive care medicine. More specifically, the prevalence, pathomechanisms and impact of neurological manifestations are reported. The most common neurological manifestations of critically ill COVID-19 patients are cerebrovascular complications, encephalopathies and intensive care unit-acquired weakness (ICUAW). A relevant direct pathophysiological effect by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) itself has not yet been established with certainty. In fact, indirect systemic inflammatory processes triggered by the viral infection and side effects of intensive care treatment are much more likely to cause the reported sequelae. The impact of the pandemic on patients with neurological disorders and neurointensive care medicine is far-reaching but not yet sufficiently studied.

Guillain-Barre syndrome following COVID-19 vaccines: A review of literature

Objective

This study aimed to retrospectively analyze reported Guillain-Barré syndrome (GBS) cases that occurred after COVID-19 vaccination.

Methods

Case reports of GBS following COVID-19 vaccination that were published before May 14, 2022, were retrieved from PubMed. The cases were retrospectively analyzed for their basic characteristics, vaccine types, the number of vaccination doses before onset, clinical manifestations, laboratory test results, neurophysiological examination results, treatment, and prognosis.

Results

Retrospective analysis of 60 case reports revealed that post-COVID-19 vaccination GBS occurred mostly after the first dose of the vaccination (54 cases, 90%) and was common for DNA vaccination (38 cases, 63%), common in middle-aged and elderly people (mean age: 54.5 years), and also common in men (36 cases, 60%). The mean time from vaccination to onset was 12.3 days. The classical GBS (31 cases, 52%) was the major clinical classification and the AIDP subtype (37 cases, 71%) was the major neurophysiological subtype, but the positive rate of anti-ganglioside antibodies was low (7 cases, 20%). Bilateral facial nerve palsy (76% vs 18%) and facial palsy with distal paresthesia (38% vs 5%) were more common for DNA vaccination than for RNA vaccination.

Conclusion

After reviewing the literature, we proposed a possible association between the risk of GBS and the first dose of the COVID-19 vaccines, especially DNA vaccines. The higher rate of facial involvement and a lower positive rate of anti-ganglioside antibodies may be a characteristic feature of GBS following COVID-19 vaccination. The causal relationship between GBS and COVID-19 vaccination remains speculative, more research is needed to establish an association between GBS and COVID-19 vaccination. We recommend surveillance for GBS following vaccination, because it is important in determining the true incidence of GBS following COVID-19 vaccination, as well as in the development of a more safer vaccine.

Decreased Incidence of Guillain-Barré Syndrome during the COVID-19 Pandemic: A Retrospective Population-Based Study

BACKGROUND

Guillain-Barré syndrome is an immune-mediated acute inflammatory polyneuropathy that is associated with various triggers, including certain infections and vaccines. It has been suggested that both SARS-CoV-2 infection and vaccination may be triggering factors for Guillain-Barré syndrome, but evidence remains equivocal. Here, we conducted a population-based incidence study of Guillain-Barré syndrome spanning the 3 years immediately prior to and the 2 years during the pandemic.

METHODS

Cases were identified by searching a regional diagnostic database for the ICD-10 code for Guillain-Barré syndrome. Individuals who fulfilled the Brighton criteria for Guillain-Barré syndrome were included. Information on clinical presentation, laboratory values, and vaccination status were retrieved from medical records. We calculated the incidence immediately prior to and during the pandemic.

RESULTS

The Guillain-Barré syndrome incidence rate was 1.35/100,000 person-years for the pre-pandemic period and 0.66/100,000 person-years for the pandemic period (incidence rate ratio: 0.49; p = 0.003). Three cases were temporally associated with SARS-CoV-2 infection and 1 case each to the AstraZeneca and Pfizer-BioNTech COVID-19 vaccines.

CONCLUSIONS

Our results show that the incidence of Guillain-Barré syndrome decreased during the pandemic. This is most likely due to decreased prevalence of triggering infections due to social restrictions. Our findings do not support a causal relationship between Guillain-Barré syndrome and COVID-19.

Neurological Manifestations of SARS-CoV2 Infection: A Narrative Review

The COVID-19 virus frequently causes neurological complications. These have been described in various forms in adults and children. Headache, seizures, coma, and encephalitis are some of the manifestations of SARS-CoV-2-induced neurological impairment. Recent publications have revealed important aspects of viral pathophysiology and its involvement in nervous-system impairment in humans. We evaluated the latest literature describing the relationship between COVID-19 infection and the central nervous system. We searched three databases for observational and interventional studies in adults published between December 2019 and September 2022. We discussed in narrative form the neurological impairment associated with COVID-19, including clinical signs and symptoms, imaging abnormalities, and the pathophysiology of SARS-CoV2-induced neurological damage.

Guillain-Barré syndrome in an era of global infections and 21st century vaccination

PURPOSE OF REVIEW

Guillain-Barre syndrome is sometimes a severe and disabling postinfectious neuromuscular paralysis that is causally associated with a number of well defined infections, and occasionally with immunization. The severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) pandemic and the worldwide immunization programme provoked fears of an epidemic of coronavirus disease 2019 (COVID-19) related disease. As we emerge from the pandemic this review summarises some of the huge volume of publications about Guillain-Barre syndrome (GBS), COVID-19 and immunisation against it.

RECENT FINDINGS

In the early months of COVID-19, there were concerns of significant numbers of cases of GBS resulting from SARS-CoV-2 infection. Large epidemiological studies have provided reassurance that the association of GBS with COVID-19 is small or absent. Despite considerable efforts, plausible pathogenic mechanisms aligned with our understanding of GBS causation have not been identified. Reliable data from national surveillance of COVID-19 vaccinations have shown GBS to occur at about 5.8 cases per million first doses of adenovirus vectored COVID-19 vaccines, otherwise not distinguishable from incident naturally occurring cases. However, this risk is far outweighed by the protective benefits of vaccination in the at-risk older deciles of age.

SUMMARY

With no obvious link of GBS to COVID-19 epitopes, in particular the spike (S-)protein, but a clearly demonstrable causation in some susceptible individuals from the global rollout of novel adenovirus vectored vaccine technologies, adenoviruses are of significant interest in the pathogenesis of GBS as well as vectors in their many expanding pharmaceutical applications.

Case Report: Post-COVID-19 Vaccine Recurrence of Guillain-Barré Syndrome Following an Antecedent Parainfectious COVID-19-Related GBS

Guillain-Barré syndrome (GBS) is an autoimmune neurological disorder often preceded by viral illnesses or, more rarely, vaccinations. We report on a unique combination of postcoronavirus disease 2019 (COVID-19) vaccine GBS that occurred months after a parainfectious COVID-19-related GBS. Shortly after manifesting COVID-19 symptoms, a 57-year-old man developed diplopia, right-side facial weakness, and gait instability that, together with electrophysiology and cerebrospinal fluid examinations, led to a diagnosis of post-COVID-19 GBS. The involvement of cranial nerves and IgM seropositivity for ganglioside GD1b were noteworthy. COVID-19 pneumonia, flaccid tetraparesis, and autonomic dysfunction prompted his admission to ICU. He recovered after therapy with intravenous immunoglobulins (IVIg). Six months later, GBS recurred shortly after the first dose of the Pfizer/BioNTech vaccine. Again, the GBS diagnosis was confirmed by cerebrospinal fluid and electrophysiology studies. IgM seropositivity extended to multiple gangliosides, namely for GM3/4, GD1a/b, and GT1b IgM. An IVIg course prompted complete recovery. This case adds to other previously reported observations suggesting a possible causal link between SARS-CoV-2 and GBS. Molecular mimicry and anti-idiotype antibodies might be the underlying mechanisms. Future COVID-19 vaccinations/revaccinations in patients with previous para-/post-COVID-19 GBS deserve a reappraisal, especially if they are seropositive for ganglioside antibodies.

Pathological Features and Neuroinflammatory Mechanisms of SARS-CoV-2 in the Brain and Potential Therapeutic Approaches

The number of deaths has been increased due to COVID-19 infections and uncertain neurological complications associated with the central nervous system. Post-infections and neurological manifestations in neuronal tissues caused by COVID-19 are still unknown and there is a need to explore how brainstorming promoted congenital impairment, dementia, and Alzheimer's disease. SARS-CoV-2 neuro-invasion studies in vivo are still rare, despite the fact that other beta-coronaviruses have shown similar properties. Neural (olfactory or vagal) and hematogenous (crossing the blood-brain barrier) pathways have been hypothesized in light of new evidence showing the existence of SARS-CoV-2 host cell entry receptors into the specific components of human nerve and vascular tissue. Spike proteins are the primary key and structural component of the COVID-19 that promotes the infection into brain cells. Neurological manifestations and serious neurodegeneration occur through the binding of spike proteins to ACE2 receptor. The emerging evidence reported that, due to the high rate in the immediate wake of viral infection, the olfactory bulb, thalamus, and brain stem are intensely infected through a trans-synaptic transfer of the virus. It also instructs the release of chemokines, cytokines, and inflammatory signals immensely to the blood-brain barrier and infects the astrocytes, which causes neuroinflammation and neuron death; and this induction of excessive inflammation and immune response developed in more neurodegeneration complications. The present review revealed the pathophysiological effects, molecular, and cellular mechanisms of possible entry routes into the brain, pathogenicity of autoantibodies and emerging immunotherapies against COVID-19.

What SARS-CoV-2 does to our brains

Neurological symptoms in SARS-CoV-2-infected patients have been reported, but their cause remains unclear. In theory, the neurological symptoms observed after SARS-CoV-2 infection could be (1) directly caused by the virus infecting brain cells, (2) indirectly by our body’s local or systemic immune response toward the virus, (3) by coincidental phenomena, or (4) a combination of these factors. As indisputable evidence of intact and replicating SARS-CoV-2 particles in the central nervous system (CNS) is currently lacking, we suggest focusing on the host’s immune reaction when trying to understand the neurocognitive symptoms associated with SARS-CoV-2 infection. In this perspective, we discuss the possible immune-mediated mechanisms causing functional or structural CNS alterations during acute infection as well as in the post-infectious context. We also review the available literature on CNS affection in the context of COVID-19 infection, as well as observations from animal studies on the molecular pathways involved in sickness behavior.

Chronic Inflammatory Demyelinating Polyneuropathy Post-mRNA-1273 Vaccination

Massive efforts are being made to develop coronavirus disease 2019 (COVID-19) vaccines at an unprecedented rate. The vaccinations' adverse impact profile, on the other hand, has not been well established. Neurological complications are increasingly reported as a result of these vaccines. One such complication identified is immune-mediated inflammatory polyneuropathy, which affects peripheral nerves and neurons. We report a case of chronic inflammatory demyelinating polyneuropathy (CIDP) post-mRNA-1273 (Moderna) COVID-19 vaccine. Recognizing this complication and distinguishing it from Guillain-Barré syndrome enables timely initiation of treatment. Additionally, our report highlights a possible link between vaccination and subsequent development of CIDP, but conclusive evidence of a causal relationship requires more extensive studies.