Opsoclonus-Myoclonus-Ataxia Syndrome Related to the Novel Coronavirus (COVID-19)

Opsoclonus-Myoclonus-Ataxia Syndrome Due to Covid-19

Opsoclonus-myoclonus syndrome (OMS) as a rare neurological encephalopathic entity associated with non-specific infections or cancer processes has been repeatedly described in the setting of SARS-CoV-2 infection. We report a case of a 53-year-old man with SARS-CoV-2 infection, who developed clinical features of opsoclonus-myoclonus ataxia syndrome including cognitive impairments with a prolonged course of disease. Of particular note, cerebrospinal fluid (CSF) analysis revealed the production of myelin oligodendrocyte glycoprotein (MOG) antibodies, suggesting an underlying neuroimmunological mechanism associated with infection with the novel SARS-CoV-2 virus.

COVID-19 and children's eyes

Letter

Update on coronavirus disease 2019: Ophthalmic Manifestations and Adverse Reactions to Vaccination

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 was one of the most devastating public health issues in recent decades. The ophthalmology community is as concerned about the COVID-19 pandemic as the global public health community is, as COVID-19 was recognized to affect multiple organs in the human body, including the eyes, early in the course of the outbreak. Ophthalmic manifestations of COVID-19 are highly variable and could range from mild ocular surface abnormalities to potentially sight and life-threatening orbital and neuro-ophthalmic diseases. Furthermore, ophthalmic manifestations may also be the presenting or the only findings in COVID-19 infections. Meanwhile, global vaccination campaigns to attain herd immunity in different populations are the major strategy to mitigate the pandemic. As novel vaccinations against COVID-19 emerged, so were reports on adverse ophthalmic reactions potentially related to such. As the world enters a post-pandemic state where COVID-19 continues to exist and evolve as an endemic globally, the ophthalmology community ought to be aware of and keep abreast of the latest knowledge of ophthalmic associations with COVID-19 and its vaccinations. This review is a summary of the latest literature on the ophthalmic manifestations of COVID-19 and the adverse ophthalmic reactions related to its vaccinations.

De Novo Movement Disorders Associated with COVID-19- A Systematic Review of Individual Patients

Background

COVID-19 infection is associated with neurological manifestations, including various types of movement disorders (MD). A thorough review of individual patients with COVID-19-induced MD would help in better understanding the clinical profile and outcome of these patients and in prognostication.

Objective

We conducted an individual patient-systematic review to study the clinical and imaging profile and outcomes of patients with COVID-19-associated MD.

Methods

A systematic literature search of PubMed, EMBASE, and Cochrane databases was conducted by two independent reviewers. Individual patient data COVID from case reports and case series on COVID-19-associated MD, published between December 2019 and December 2022, were extracted and analyzed.

Results

Data of 133 patients with COVID-19-associated MD from 82 studies were analyzed. Mean age was 55 ± 18 years and 77% were males. A mixed movement disorder was most commonly seen (41%); myoclonus-ataxia was the most frequent (44.4%). Myoclonus significantly correlated with age (odds ratio (OR) 1.02 P = 0.03, CI 1-1.04). Tremor had the longest latency to develop after SARS-CoV-2 infection [median (IQR) 21 (10-40) days, P = 0.009, CI 1.01-1.05]. At short-term follow-up, myoclonus improved (OR 14.35, P value = 0.01, CI 1.71-120.65), whereas parkinsonism (OR 0.09, P value = 0.002, CI 0.19-0.41) and tremor (OR 0.16, P value = 0.016, CI 0.04-0.71) persisted.

Conclusion

Myoclonus-ataxia was the most common movement disorder after COVID-19 infection. Myoclonus was seen in older individuals and usually improved. Tremor and parkinsonism developed after a long latency and did not improve in the short-term.

COVID19-associated new-onset movement disorders: a follow-up study

BACKGROUND

Neurological symptoms are common manifestation in acute COVID-19. This includes hyper- and hypokinetic movement disorders. Data on their outcome, however, is limited.

METHODS

Cases with new-onset COVID-19-associated movement disorders were identified by searching the literature. Authors were contacted for outcome data which were reviewed and analyzed.

RESULTS

Movement disorders began 12.6 days on average after the initial onset of COVID-19. 92% of patients required hospital admission (mean duration 23 days). In a fraction of patients (6 of 27; 22%; 4 males/2 females, mean age 66.8 years) the movement disorder (ataxia, myoclonus, tremor, parkinsonism) was still present after a follow-up period of 7.5 ± 3 weeks. Severe COVID-19 in general and development of encephalopathy were risk factors, albeit not strong predictors, for the persistence.

CONCLUSIONS

The prognosis of new-onset COVID-19-associated movement disorder appears to be generally good. The majority recovered without residual symptoms within several weeks or months. Permanent cases may be due to unmasking of a previous subclinical movement disorder or due to vascular/demyelinating damage. Given the relatively low response rate of one third only and the heterogeneity of mechanisms firm conclusions on the (long-term) outome cannot, however, be drawn.

An eye to the future: Acute and long-term neuro-ophthalmological and neurological complications of COVID-19

COVID-19 has had a significant impact on the global population and has produced compelling evidence of non-pulmonary organ dysfunction, including the nervous system. It is vital that specialists in ophthalmology and neurology are informed of the potential complications of COVID-19 and gain a deeper understanding of how COVID-19 can cause diseases of the nervous system. In this review we detail four possible mechanisms by which COVID-19 infection may result in neurological or neuro-ophthalmological complications: (1) Toxic and metabolic effects of severe pulmonary COVID-19 disease on the neural axis including hypoxia and the systemic hyper-inflammatory state, (2) endothelial dysfunction, (3) dysimmune responses directed again the neuroaxis, and (4) direct neuro-invasion and injury by the virus itself. We explore the pathological evidence for each of these and how they may link to neuro-ophthalmological disorders. Finally, we explore the evidence for long-term neurological and neuro-ophthalmological complications of COVID-19, with a focus on neurodegeneration.

Brain stem encephalitis is a rare complication of COVID-19

Here, we describe the clinical phenotype of SARS-CoV-2-related CNS disease and evaluate the SARS-CoV-2 antibody index as a tool to differentiate between a direct (viral) and indirect etiology. Out of >4000 hospitalized patients with COVID-19, we included 13 patients with neurological symptoms with suspicion of neuroinflammation. On clinical grounds, eight were classified as having a possible/probable relationship between neurological symptoms and COVID-19. A clinically distinctive phenotype of brainstem and cerebellar symptoms was seen in 6/8 patients. As we found a positive SARS-CoV-2 antibody index in 3/5 patients, indicating specific intrathecal SARS-CoV-2 IgG production, a direct link with SARS-CoV-2 is likely.

Opsoclonus Myoclonus Ataxia Syndrome Due to SARS-CoV-2

Opsoclonus myoclonus syndrome (OMS)/opsoclonus myoclonus ataxia syndrome (OMAS), also known as Kinsbourne's syndrome or 'dancing eyes-dancing feet' syndrome, is a rare central nervous system manifestation of COVID-19 but an increasing number of articles have reported patients in whom COVID-19 was complicated by OMS/OMAS. This narrative review aims at summarising and discussing current knowledge about the clinical presentation, diagnosis, treatment and outcome of SARS-CoV-2 associated OMS/OMAS. Altogether, 29 articles reporting 45 patients with SARS-CoV-2 associated OMS/OMAS were retrieved. Their ages ranged from 2 to 88 years. Three patients were children and the remainder adults. Gender was male in 32 patients and female in 13 patients. Opsoclonus was described in 29 patients, which was associated with myoclonus in 28 cases. Myoclonus was described in 43 patients, which was associated with opsoclonus and ataxia in 18 patients. Cerebral magnetic resonance imaging and cerebrospinal fluid investigations were not informative in the majority of the cases. OMS/OMAS was treated with steroids in 28 patients and with intravenous immunoglobulin (IVIG) in 15 patients. Clonazepam was given to 18 patients, levetiracetam to 13 patients, and sodium valproate to eight patients. Complete recovery was achieved in 12 cases and incomplete recovery in 22 cases. Diagnosing SARS-CoV-2 associated OMS/OMAS requires extensive neurological work up and exclusion of various differentials. SARS-CoV-2 associated OMS/OMAS may not always present with the full spectrum of manifestations but as an abortive syndrome. OMS/OMAS should not be missed as it usually responds favourably to steroids or IVIG.

Efferent neuro-ophthalmic complications of coronavirus disease 2019

PURPOSE OF REVIEW

We set out to describe efferent neuro-ophthalmological complications that have been reported in association with coronavirus disease 2019 (COVID-19) infection. We describe syndromes affecting ocular motility and elaborate on mechanisms of disease, including para-infectious inflammation, hypercoagulability, endothelial damage, and direct neurotropic viral invasion. Despite global vaccination programs, COVID-19 continues to pose an international threat that may rarely result in diplopia or nystagmus.

RECENT FINDINGS

Efferent complications include cranial nerve palsies leading to diplopia, either isolated or in association with Miller Fisher syndrome. Nystagmus has been observed in the setting of hemorrhagic acute necrotizing encephalopathy and brainstem infarcts, and opsoclonus syndrome has been described.

SUMMARY

Observed neuro-ophthalmic associations need to be confirmed through larger comparative studies. Meanwhile, the range of possible complications should be recognized by neurologists and ophthalmologists alike, to facilitate faster diagnosis and treatment of both COVID-19 and its neuro-ophthalmic manifestations.

Update on overview of ocular manifestations of COVID-19

The coronavirus disease 2019 (COVID-19) has become the most critical health crisis at present, and research is continued about the exact pathophysiology, presentations, and complications of this pandemic. It influences several organs, and many studies have addressed the organs, the involvement of which during the COVID-19 results in patients' death. One of the important organs that can be involved during COVID-19, which is also a transmission route of the disease, is the eye. According to the evidence, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can have ocular manifestations and complications. According to the literature, conjunctivitis is the most common presentation, which can develop at any stage of COVID-19 (during and even after the disease), and the major pathophysiology of the eye involvement during the disease is attributed to the direct effect of the virus on the eyes, tissue damage caused by inflammation, underlying diseases, and the adverse effect of the medications prescribed. There are also reports of life-threatening complications, such as rhino-orbital cerebral mucormycosis, which require urgent treatment and are associated with a great mortality rate. Ocular manifestations may also be the presentation of a life-threatening event, such as stroke; therefore, it is necessary to pay great attention to the ocular manifestations during COVID-19. In this review, after about 2 years of the pandemic started, we present a narrative review on ocular manifestations during COVID-19, categorized into three main categories; ophthalmic, orbital, and neuro-ophthalmological manifestations with a detailed description of the presenting symptoms, risk factor, diagnostic, and therapeutic strategies suggested for each.

Postinfectious SARS-CoV-2 Opsoclonus-Myoclonus-Ataxia Syndrome

BACKGROUND

The opsoclonus-myoclonus-ataxia syndrome (OMAS) represents a pathophysiology and diagnostic challenge. Although the diverse etiologies likely share a common mechanism to generate ocular, trunk, and limb movements, the underlying cause may be a paraneoplastic syndrome, as the first sign of cancer, or may be a postinfectious complication, and thus, the outcome depends on identifying the trigger mechanism. A recent hypothesis suggests increased GABAA receptor sensitivity in the olivary-oculomotor vermis-fastigial nucleus-premotor saccade burst neuron circuit in the brainstem. Therefore, OMAS management will focus on immunosuppression and modulation of GABAA hypersensitivity with benzodiazepines.

METHODS

We serially video recorded the eye movements at the bedside of 1 patient with SARS-CoV-2-specific Immunoglobulin G (IgG) serum antibodies, but twice-negative nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR). We tested cerebrospinal fluid (CSF), serum, and nasopharyngeal samples. After brain MRI and chest, abdomen, and pelvis CT scans, we treated our patient with clonazepam and high-dose Solu-MEDROL, followed by a rituximab infusion after her formal eye movement analysis 10 days later.

RESULTS

The recordings throughout her acute illness demonstrated different eye movement abnormalities. While on high-dose steroids and clonazepam, she initially had macrosaccadic oscillations, followed by brief ocular flutter during convergence the next day; after 10 days, she had bursts of opsoclonus during scotopic conditions with fixation block but otherwise normal eye movements. Concern for a suboptimal response to high-dose Solu-MEDROL motivated an infusion of rituximab, which induced remission. An investigation for a paraneoplastic etiology was negative. CSF testing showed elevated neuron-specific enolase. Serum IgG to Serum SARS-CoV2 IgG was elevated with negative RT-PCR nasopharyngeal testing.

CONCLUSION

A recent simulation model of macrosaccadic oscillations and OMAS proposes a combined pathology of brainstem and cerebellar because of increased GABAA receptor sensitivity. In this case report, we report 1 patient with elevated CSF neuronal specific enolase, macrosaccadic oscillations, ocular flutter, and OMAS as a SARS-CoV-2 postinfectious complication. Opsoclonus emerged predominantly with fixation block and suppressed with fixation, providing support to modern theories on the mechanism responsible for these ocular oscillations involving cerebellar-brainstem pathogenesis.

Post-infectious cerebellar ataxia following COVID-19 in a patient with epilepsy

Background

Various neurological manifestations have been described in relation to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19). However, the development of cerebellar ataxia after recovery from COVID-19 is rare. We present a case of cerebellar ataxia 3 weeks after recovery from COVID-19.

Case Presentation

A 70-year-old male patient from an urban area of India presented with ataxia. He was hypertensive and had been receiving treatment for post-traumatic epilepsy for the previous 3 years. He had previously had laboratory-confirmed COVID-19 infection with mild symptoms that resolved within 2 weeks. However, 3 weeks after symptom improvement, he developed severe pan-cerebellar ataxia. Investigations were suggestive of post-infectious cerebellar ataxia. Other causes of ataxia were excluded. He responded well to pulse methylprednisolone therapy and was discharged with mild tremor and ataxia.

Conclusion

Post-infectious cerebellar ataxia is an unusual presentation after COVID-19. The clinician should be aware of such complications following COVID-19 infection as early diagnosis and proper management leads to better outcomes in many patients.

Temporal Changes in Brain Perfusion in a Patient with Myoclonus and Ataxia Syndrome Associated with COVID-19

Myoclonus and ataxia, with or without opsoclonus, have recently been recognized as a central nervous system syndrome associated with coronavirus disease-2019 (COVID-19). A 52-year-old Japanese man developed myoclonus and ataxia 16 days after the onset of COVID-19. Brain single-photon emission computed tomography (SPECT) revealed hyperperfusion in the cerebellum and hypoperfusion in the cerebral cortices with frontal predominance during the acute stage, which improved over two months. This study indicates that brain perfusion SPECT can be effective in detecting functional alterations in COVID-19-related myoclonus and ataxia.

Neuroradiologic Imaging of Neurologic and Neuro-Ophthalmic Complications of Coronavirus-19 Infection

BACKGROUND

To review the literature and provide a summary of COVID-19-related neurologic and neuro-ophthalmic complications.

METHODS

The currently available literature was reviewed on PubMed and Google Scholar using the following keywords for searches: CNS, Neuro-Ophthalmology, COVID-19, SARS-CoV-2, coronavirus, optic neuritis, pseudotumor cerebri, Acute Disseminated Encephalomyelitis, posterior reversible encephalopathy syndrome (PRES), meningitis, encephalitis, acute necrotizing hemorrhagic encephalopathy, and Guillain-Barré and Miller Fisher syndromes.

RESULTS

Neuroradiologic findings of neurologic and neuro-ophthalmologic complications in relationship to COVID-19 infection were reviewed. Afferent visual pathway-related disorders with relevant imaging manifestations included fundus nodules on MRI, papilledema and pseudotumor cerebri syndrome, optic neuritis, Acute Disseminated Encephalomyelitis, vascular injury with thromboembolism and infarct, leukoencephalopathy, gray matter hypoxic injury, hemorrhage, infectious meningitis/encephalitis, acute necrotizing hemorrhagic encephalopathy, and PRES. Efferent visual pathway-related complications with relevant imaging manifestations were also reviewed, including orbital abnormalities, cranial neuropathy, Guillain-Barré and Miller Fisher syndromes, and nystagmus and other eye movement abnormalities related to rhombencephalitis.

CONCLUSION

COVID-19 can cause central and peripheral nervous system disease, including along both the afferent and efferent components of visual axis. Manifestations of disease and long-term sequela continue to be studied and described. Familiarity with the wide variety of neurologic, ophthalmic, and neuroradiologic presentations can promote prompt and appropriate treatment and continue building a framework to understand the underlying mechanism of disease.

Movement Disorders Associated with COVID-19

As neurological complications associated with COVID-19 keep unfolding, the number of cases with COVID-19-associated de novo movement disorders is rising. Although no clear pathomechanistic explanation is provided yet, the growing number of these cases is somewhat alarming. This review gathers information from 64 reports of de novo movement disorders developing after/during infection with SARS-CoV-2. Three new cases with myoclonus occurring shortly after a COVID-19 infection are also presented. Treatment resulted in partial to complete recovery in all three cases. Although the overall percentage of COVID-19 patients who develop movement disorders is marginal, explanations on a probable causal link have been suggested by numerous reports; most commonly involving immune-mediated and postinfectious and less frequently hypoxic-associated and ischemic-related pathways. The current body of evidence points myoclonus and ataxia out as the most frequent movement disorders occurring in COVID-19 patients. Some cases of tremor, chorea, and hypokinetic-rigid syndrome have also been observed in association with COVID-19. In particular, parkinsonism may be of dual concern in the setting of COVID-19; some have linked viral infections with Parkinson's disease (PD) based on results from cerebrospinal fluid analyses, and PD is speculated to impact the outcome of COVID-19 in patients negatively. In conclusion, the present paper reviewed the demographic, clinical, and treatment-associated information on de novo movement disorders in COVID-19 patients in detail; it also underlined the higher incidence of myoclonus and ataxia associated with COVID-19 than other movement disorders.

Anti-GAD associated post-infectious cerebellitis after COVID-19 infection

The coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), continues to spread rapidly all over the world. Besides severe pneumonia, it causes multisystemic disease, including neurological findings. Here, we present a patient with anti–glutamic acid decarboxylase (anti-GAD) antibody-associated cerebellitis developed after COVID-19 infection. The patient responded well to the immune treatments. Our knowledge about SARS-CoV-2 infection–related neurological disorders is limited. New data are needed to recognize the clinical spectrum of autoimmune neurological disorders that emerges after SARS-CoV-2 infection.

New-Onset Movement Disorders Associated with COVID-19

Introduction

Movement disorders are increasingly described in hospitalized and milder cases of SARS-CoV-2 infection, despite a very low prevalence compared to the total patients.

Methods

We reviewed the scientific literature published in English, spanning from the initial descriptions of COVID-19 until January 25, 2021, in the PubMed/MEDLINE database.

Results

We identified 93 new-onset movement disorders cases (44 articles) from 200 papers screened in the database or reference lists. Myoclonus was present in 63.4% (n = 59), ataxia in 38.7% (n = 36), action/postural tremor in 10.8% (n = 10), rigid-akinetic syndrome in 5.38% (n = 5), oculomotor abnormalities in 20.4% (n = 19), catatonia in 2.1% (n = 2), dystonia in 1.1% (n = 1), chorea in 1.1% (n = 1), functional (psychogenic) movement disorders in 3.2% (n = 3) of the reported COVID-19 cases with any movement disorder. Encephalopathy was a common association (n = 37, 39.78%).

Discussion

Comprehensive neurophysiological, clinical, and neuroimaging descriptions of movement disorders in the setting of SARS-CoV-2 infection are still lacking, and their pathophysiology may be related to inflammatory, postinfectious, or even indirect mechanisms not specific to SARS-CoV-2, such as ischemic-hypoxic brain insults, drug effects, sepsis, kidney failure. Cortical/subcortical myoclonus, which the cited secondary mechanisms can largely cause, seems to be the most common hyperkinetic abnormal movement, and it might occur in association with encephalopathy and ataxia.

Conclusion

This brief review contributes to the clinical description of SARS-CoV-2 potential neurological manifestations, assisting clinical neurologists in identifying features of these uncommon syndromes as a part of COVID-19 symptomatology.

Highlights

- Movement disorders are probably uncommon neurological manifestations in SARS-CoV-2 infection;- Myoclonus is the most reported movement disorder associated with COVID-19, its clinical complications or pharmacological management;- The pathophysiology is yet not well-understood but can include systemic inflammation, autoimmune mechanisms, or hypoxia.

Post-COVID Opsoclonus Myoclonus Syndrome: A Case Report From Pakistan

Background: Coronavirus disease-2019 (COVID-19), caused by the severe acute respiratory distress syndrome–coronavirus-2 (SARS-CoV-2), is primarily a respiratory infection but has been recently associated with a variety of neurological symptoms. We present herewith a COVID-19 case manifesting as opsoclonus-myoclonus syndrome (OMS), a rare neurological disorder.

Case Presentation: A 63-year-old male diagnosed with COVID-19 infection developed behavioral changes, confusion, and insomnia followed by reduced mobility and abnormal eye movements within 48 h of recovery from respiratory symptoms associated with COVID-19. On examination, he had rapid, chaotic, involuntary saccadic, multidirectional eye movements (opsoclonus), and limb myoclonus together with truncal ataxia. CSF analysis, MRI of the brain, and screening for anti-neuronal and encephalitis related antibodies were negative. Extensive testing revealed no underlying malignancy. The patient was successfully treated with intravenous immunoglobulin (IVIG) with complete resolution of symptoms within 4 weeks of treatment.

Conclusion: COVID-19 infection can be associated with the manifestation of opsoclonus myoclonus syndrome, a rare neurological disorder that can be treated with IVIG if not responsive to corticosteroids.

Afferent and Efferent Neuro-Ophthalmic Complications of Coronavirus Disease 19

PURPOSE

To provide a summary of the neuro-ophthalmic manifestations of coronavirus disease 19 (COVID-19) documented in the literature thus far.

METHODS

The PubMed and Google Scholar databases were searched using the keywords: Neuro-Ophthalmology, COVID-19, SARS-CoV-2, and coronavirus. A manual search through reference lists of relevant articles was also performed.

RESULTS/CONCLUSIONS

The literature on COVID-associated neuro-ophthalmic disease continues to grow. Afferent neuro-ophthalmic complications associated with COVID-19 include optic neuritis, papillophlebitis, papilledema, visual disturbance associated with posterior reversible encephalopathy syndrome, and vision loss caused by stroke. Efferent neuro-ophthalmic complications associated with COVID-19 include cranial neuropathies, Miller Fisher syndrome, Adie's pupils, ocular myasthenia gravis, nystagmus and eye movement disorders. Proposed mechanisms of neurologic disease include immunologic upregulation, vasodilation and vascular permeability, endothelial dysfunction, coagulopathy, and direct viral neurotropism. When patients present to medical centers with new onset neuro-ophthalmic conditions during the pandemic, COVID-19 infection should be kept on the differential.

Subacute cerebellar ataxia following respiratory symptoms of COVID-19: a case report

Background

Severe acute respiratory syndrome virus 2 (SARS-CoV-2) is spreading globally and causes most frequently fever and respiratory symptoms, i.e. Coronavirus disease 2019 (COVID-19), however, distinct neurological syndromes associated with SARS-CoV-2 infection have been described. Among SARS-CoV-2-infections-associated neurological symptoms fatigue, headache, dizziness, impaired consciousness and anosmia/ageusia are most frequent, but less frequent neurological deficits such as seizures, Guillain-Barré syndrome or ataxia may also occur.

Case presentation

Herein we present a case of a 62-year-old man who developed a subacute cerebellar syndrome with limb-, truncal- and gait ataxia and scanning speech 1 day after clinical resolution of symptomatic SARS-CoV-2 infection of the upper airways. Apart from ataxia, there were no signs indicative of opsoclonus myoclonus ataxia syndrome or Miller Fisher syndrome. Cerebral magnetic resonance imaging showed mild cerebellar atrophy. SARS-CoV-2 infection of the cerebellum was excluded by normal cerebrospinal fluid cell counts and, most importantly, absence of SARS-CoV-2 RNA or intrathecal SARS-CoV-2-specific antibody production. Other causes of ataxia such as other viral infections, other autoimmune and/or paraneoplastic diseases or intoxication were ruled out. The neurological deficits improved rapidly after high-dose methylprednisolone therapy.

Conclusions

The laboratory and clinical findings as well as the marked improvement after high-dose methylprednisolone therapy suggest a post-infectious, immune-mediated cause of ataxia. This report should make clinicians aware to consider SARS-CoV-2 infection as a potential cause of post-infectious neurological deficits with an atypical clinical presentation and to consider high-dose corticosteroid treatment in case that a post-infectious immune-mediated mechanism is assumed.

Isolated generalized myoclonus immune-mediated by SARS-CoV-2: an illustrative videotaped case

Myoclonus in the context of COVID-19 is an increasingly recognized condition. The occurrence in an ICU context in hypoxic patients, with metabolic disorders, taking several types of medication, makes difficult to establish a precise cause. Also, the implication of SARS-CoV-2 by direct invasion of the CNS or by immune-mediated phenomena is not yet clear. Currently, a dozen of cases of myoclonus as a predominant clinical manifestation, immune-mediated by SARS-Cov-2 are published. In all these cases, myoclonus was preceded by respiratory or other suggestive symptoms (e.g., anosmia) for this infection making straightforward the causal link. We describe a case of an isolated generalized myoclonus without other clinical complaints nor chest CT scan abnormalities nor SARS-CoV-2 RNA detection on nasopharyngeal swabs and on the CSF, as a para-infectious phenomenon of COVID-19 infection with excellent response to steroids perfusion. This challenging diagnosis was made upon confirmation of seroconversion (serology was negative at admission, then positive for IgM at day 6, then for both IgM and IgG at day 10) underlying that repeating serology is a diagnostic key to capture a similar findings.

Myoclonus and cerebellar ataxia associated with COVID-19: a case report and systematic review

Background

Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic in December 2019, neurological manifestations have been recognized as potential complications. Relatively rare movement disorders associated with COVID-19 are increasingly reported in case reports or case series. Here, we present a case and systematic review of myoclonus and cerebellar ataxia associated with COVID-19.

Methods

A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guideline using the PubMed and Ovid MEDLINE databases, from November 1, 2019 to December 6, 2020.

Results

51 cases of myoclonus or ataxia associated with COVID-19, including our case, were identified from 32 publications. The mean age was 59.6 years, ranging from 26 to 88 years, and 21.6% were female. Myoclonus was multifocal or generalized and had an acute onset, usually within 1 month of COVID-19 symptoms. Myoclonus occurred in isolation (46.7%), or with ataxia (40.0%) or cognitive changes (30.0%). Most cases improved within 2 months, and treatment included anti-epileptic medications or immunotherapy. Ataxia had an acute onset, usually within 1 month of COVID-19 symptoms, but could be an initial symptom. Concurrent neurological symptoms included cognitive changes (45.5%), myoclonus (36.4%), or a Miller Fisher syndrome variant (21.2%). Most cases improved within 2 months, either spontaneously or with immunotherapy.

Conclusions

This systematic review highlights myoclonus and ataxia as rare and treatable post-infectious or para-infectious, immune-mediated phenomena associated with COVID-19. The natural history is unknown and future investigation is needed to further characterize these movement disorders and COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-021-10458-0.

Opsoclonus-Myoclonus-Ataxia Syndrome (OMAS) Associated with SARS-CoV-2 Infection: Post-Infectious Neurological Complication with Benign Prognosis

The novel coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) is the cause of the COVID-19 pandemic [5]. SARS-Cov-2 demonstrates partial resemblance to SARS-CoV and MERS-CoV in phylogenetic analysis, clinical manifestations, and pathological findings [6, 7]. Reports emerging from China have described ataxia as a neurological symptom of the SARS-CoV-2 infection [5]. Opsoclonus consists of back-to-back multidirectional conjugate saccades without an inter-saccadic interval [8]. Myoclonus is defined as a sudden, brief, "shock-like", nonepileptic involuntary movement [9], which has been described as a symptom of SARS-CoV-2 infection [10]. Opsoclonus-Myoclonus-Ataxia syndrome (OMAS) associated COVID-19 infection has been reported recently [1112].

Neuro-ophthalmologic complications of coronavirus disease 2019 (COVID-19)

Multiple neuro-ophthalmological manifestations have been described in association with COVID-19. These symptoms and signs may be the result of a range of pathophysiological mechanisms throughout the course from acute illness to recovery phase. Optic nerve dysfunction, eye movement abnormalities and visual field defects have been described.