Global uncertainty in the diagnosis of neurological complications of SARS-CoV-2 infection by both neurologists and non-neurologists: An international inter-observer variability study.

INTRODUCTION: Uniform case definitions are required to ensure harmonised reporting of neurological syndromes associated with SARS-CoV-2. Moreover, it is unclear how clinicians perceive the relative importance of SARS-CoV-2 in neurological syndromes, which risks under- or over-reporting. METHODS: We invited clinicians through global networks, including the World Federation of Neurology, to assess ten anonymised vignettes of SARS-CoV-2 neurological syndromes. Using standardised case definitions, clinicians assigned a diagnosis and ranked association with SARS-CoV-2. We compared diagnostic accuracy and assigned association ranks between different settings and specialties and calculated inter-rater agreement for case definitions as "poor" (κ ≤ 0.4), "moderate" or "good" (κ > 0.6). RESULTS: 1265 diagnoses were assigned by 146 participants from 45 countries on six continents. The highest correct proportion were cerebral venous sinus thrombosis (CVST, 95.8%), Guillain-Barré syndrome (GBS, 92.4%) and headache (91.6%) and the lowest encephalitis (72.8%), psychosis (53.8%) and encephalopathy (43.2%). Diagnostic accuracy was similar between neurologists and non-neurologists (median score 8 vs. 7/10, p = 0.1). Good inter-rater agreement was observed for five diagnoses: cranial neuropathy, headache, myelitis, CVST, and GBS and poor agreement for encephalopathy. In 13% of vignettes, clinicians incorrectly assigned lowest association ranks, regardless of setting and specialty. CONCLUSION: The case definitions can help with reporting of neurological complications of SARS-CoV-2, also in settings with few neurologists. However, encephalopathy, encephalitis, and psychosis were often misdiagnosed, and clinicians underestimated the association with SARS-CoV-2. Future work should refine the case definitions and provide training if global reporting of neurological syndromes associated with SARS-CoV-2 is to be robust.

New-onset refractory status epilepticus and febrile infection-related epilepsy syndrome.

PURPOSE OF REVIEW: The concept and understanding of new-onset refractory status epilepticus (NORSE), and its subtype with prior fever known as febrile infection-related epilepsy syndrome (FIRES) have evolved in the recent past. This review aims to summarize the recent developments in the pathophysiology, diagnosis and management of these challenging conditions. RECENT FINDINGS: NORSE and FIRES can have many different causes. Although the list of possible causes is still growing, they mostly fall in the categories of autoimmune encephalitis and genetic disorders. However, despite extensive investigations, most cases of NORSE and FIRES remain cryptogenic. Recent studies have pointed towards the key role of autoinflammation as a unifying pathophysiological mechanism in these cases. These findings also support the use of immunomodulatory treatment in this setting. Consensus recommendations on the management of NORSE and FIRES have recently been published. SUMMARY: NORSE and FIRES remain challenging conditions to diagnose and treat. Recent findings from clinical and basic research and new recommendations, reviewed in this article, contribute to an emerging framework for management and future research.

SARS-CoV-2-Related Acute Necrotizing Encephalopathy of Childhood With Good Response to Tocilizumab in an Adolescent.

BACKGROUND: Acute necrotizing encephalopathy of childhood (ANEC) is a rare parainfectious neurological disorder. ANEC is associated with a high mortality rate and poor neurological outcomes. ANEC is postulated to arise from immune-mediated or metabolic processes driven by viral infections. Although there have been some case reports of acute necrotizing encephalopathy with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) coinfection in adults, paediatric cases are rare. METHODS: A single case report of SARS-CoV-2-related ANEC in an 11-year-old boy is presented through retrospective chart review. Literature search was performed using PubMed, Embase, Cochrane database, and Google Scholar to compare and analyze similar cases of parainfectious immune-mediated encephalopathies related to SARS-CoV-2 in children. RESULTS: An 11-year-old boy with acute SARS-CoV-2 infection presented with ophthalmoplegia, ataxia, and aphasia. Neuroimaging findings demonstrated significant swelling and signal changes in bilateral thalami, brainstem, and cerebellar hemispheres, consistent with ANEC. His high ANEC Severity Score indicated poor neurological prognosis. Treatment with a combination of early steroid therapy, intravenous immunoglobulin therapy, and targeted interleukin 6 (IL-6) blockade yielded good neurological improvements. Literature search identified 19 parainfectious immune-mediated neurological disorders related to SARS-CoV-2 in children. The only other pediatric ANEC case identified was postinfectious and thus not included. CONCLUSIONS: This is the first report of a pediatric case of SARS-CoV-2-related ANEC, which responded well to early immunotherapy, including IL-6 blockade. Early immunotherapy with IL-6 blockade can be considered as an adjunct in managing severe ANEC.

SARS-CoV-2 Invasion and Pathological Links to Prion Disease.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 disease, is a highly infectious and transmissible viral pathogen that continues to impact human health globally. Nearly ~600 million people have been infected with SARS-CoV-2, and about half exhibit some degree of continuing health complication, generically referred to as long COVID. Lingering and often serious neurological problems for patients in the post-COVID-19 recovery period include brain fog, behavioral changes, confusion, delirium, deficits in intellect, cognition and memory issues, loss of balance and coordination, problems with vision, visual processing and hallucinations, encephalopathy, encephalitis, neurovascular or cerebrovascular insufficiency, and/or impaired consciousness. Depending upon the patient's age at the onset of COVID-19 and other factors, up to ~35% of all elderly COVID-19 patients develop a mild-to-severe encephalopathy due to complications arising from a SARS-CoV-2-induced cytokine storm and a surge in cytokine-mediated pro-inflammatory and immune signaling. In fact, this cytokine storm syndrome: (i) appears to predispose aged COVID-19 patients to the development of other neurological complications, especially those who have experienced a more serious grade of COVID-19 infection; (ii) lies along highly interactive and pathological pathways involving SARS-CoV-2 infection that promotes the parallel development and/or intensification of progressive and often lethal neurological conditions, and (iii) is strongly associated with the symptomology, onset, and development of human prion disease (PrD) and other insidious and incurable neurological syndromes. This commentary paper will evaluate some recent peer-reviewed studies in this intriguing area of human SARS-CoV-2-associated neuropathology and will assess how chronic, viral-mediated changes to the brain and CNS contribute to cognitive decline in PrD and other progressive, age-related neurodegenerative disorders.

Encephalitis in Patients with COVID-19: A Systematic Evidence-Based Analysis.

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) predominantly infects the respiratory system, several investigations have shown the involvement of the central nervous system (CNS) along the course of the illness, with encephalitis being one of the symptoms. The objective of this systematic review was to evaluate the characteristics (clinical, neuro-radiological aspects, and laboratory features) and outcomes of encephalitis in COVID-19 patients. PubMed, Scopus, and Google Scholar databases were searched from 1 December 2019 until 21 July 2022 to identify case reports and case series published on COVID-19 associated with encephalitis. The quality of the included studies was assessed by the Joanna Briggs Institute critical appraisal checklists. This systematic review included 79 studies, including 91 COVID-19 patients (52.7% male) experiencing encephalitis, where 85.6% were adults (49.3 ± 20.2 years), and 14.4% were children (11.2 ± 7.6 years). RT-PCR was used to confirm 92.2% of the COVID-19 patients. Encephalitis-related symptoms were present in 78.0% of COVID-19 patients at the time of diagnosis. In these encephalitis patients, seizure (29.5%), confusion (23.2%), headache (20.5%), disorientation (15.2%), and altered mental status (11.6%) were the most frequently reported neurologic manifestations. Looking at the MRI, EEG, and CSF findings, 77.6%, 75.5%, and 64.1% of the patients represented abnormal results. SARS-CoV-2-associated or -mediated encephalitis were the most common type observed (59.3%), followed by autoimmune encephalitis (18.7%). Among the included patients, 66.7% were discharged (37.8% improved and 28.9% fully recovered), whereas 20.0% of the reported COVID-19-positive encephalitis patients died. Based on the quality assessment, 87.4% of the studies were of high quality. Although in COVID-19, encephalitis is not a typical phenomenon, SARS-CoV-2 seems like a neuropathogen affecting the brain even when there are no signs of respiratory illness, causing a high rate of disability and fatality.

COVID-19 mRNA vaccine-associated encephalopathy, myocarditis, and thrombocytopenia with excellent response to methylprednisolone: A case report.

INTRODUCTION: Large-scale vaccination is considered one of the most effective strategies to control the pandemic of COVID-19. Since its start, different complications have been described thought to be related to vaccination. Here, we present a rare case where encephalopathy, myocarditis, and thrombocytopenia developed simultaneously following the second dose of Pfizer-BioNTech mRNA vaccine (BNT162b2). CASE PRESENTATION: A 15-years-old female presented with fever, altered consciousness, and convulsions after taking the second shot of the vaccine. Clinical and laboratory workup was notable for the presence of thrombocytopenia and myocarditis. No alternative causes of encephalitis were found. The patient responded significantly to methylprednisolone suggesting underlying immune pathogenesis responsible for the clinical features. The diagnostic criteria for possible autoimmune encephalitis were also fulfilled. CONCLUSION: Although rare, the clinician should be aware of the possible adverse events following COVID-19 vaccination. Further research with large pooled data is needed to get more insight into its pathogenesis and causal relationship.

Lethal encephalitis in a pediatric patient with SARS-CoV-2.

BACKGROUND: SARS-CoV-2 mostly affects the respiratory system. Some studies have reported neurological disorders associated with SARS-CoV-2. Despite an increase in reported instances, encephalitis caused by COVID-19 infection is still poorly understood. CASE: We reported a rare presentation of SARS-CoV-2 in a 15-year-old patient. He had a fulminant course with encephalitis. He had mild symptoms of a COVID-19 infection five months ago and recovered without any sequel. Despite appropriate treatment, the patient had a devastating course. CONCLUSIONS: This was a severe presentation of SARS-CoV-2 with central nervous system manifestations.

Case report of acute encephalitis following the AstraZeneca COVID-19 vaccine.

Coronavirus disease 2019 (COVID-19) vaccines have proven to be safe, effective and life-saving. However, little information is available on the neurological complications of COVID-19 vaccine. Here, we report a case who developed acute encephalomyelitis 1 week after being vaccinated with AstraZeneca COVID-19 vaccine (AZ vaccine). Autoimmune/inflammatory syndrome induced by adjuvants (ASIA) was also suspected. After intravenous dexamethasone and subcutaneous fondaparinux therapy, he returned to normal life without neurological sequelae. Four months later, he received Moderna COVID-19 vaccine without any sequelae.

Deciphering the contributions of neuroinflammation to neurodegeneration: lessons from antibody-mediated encephalitis and coronavirus disease 2019.

PURPOSE OF REVIEW: Does neuroinflammation promote neurodegeneration? Does neurodegeneration promote neuroinflammation? Or, is the answer to both questions, yes? These questions have proven challenging to answer in patients with typical age-related neurodegenerative diseases in whom the onset of neuroinflammation and neurodegeneration are largely unknown. Patients recovering from diseases associated with abrupt-onset neuroinflammation, including rare forms of antibody-mediated encephalitis (AME) and common complications of novel coronavirus disease 2019 (COVID-19), provide a unique opportunity to untangle the relationship between neuroinflammation and neurodegeneration. This review explores the lessons learned from patients with AME and COVID-19. RECENT FINDINGS: Persistent cognitive impairment is increasingly recognized in patients recovering from AME or COVID-19, yet the drivers of impairment remain largely unknown. Clinical observations, neuroimaging and biofluid biomarkers, and pathological studies imply a link between the severity of acute neuroinflammation, subsequent neurodegeneration, and disease-associated morbidity. SUMMARY: Data from patients with AME and COVID-19 inform key hypotheses that may be evaluated through future studies incorporating longitudinal biomarkers of neuroinflammation and neurodegeneration in larger numbers of recovering patients. The results of these studies may inform the contributors to cognitive impairment in patients with AME and COVID-19, with potential diagnostic and therapeutic applications in patients with age-related neurodegenerative diseases.

Olfactory impairment in autoimmune encephalitis: another piece of the puzzle.

BACKGROUND: Despite being long neglected, olfaction has recently become a focus of intense research in neuroscience, as smell impairment has been consistently documented in both neurodegenerative and neuroinflammatory diseases. Considering the close anatomo-functional correlations between the limbic system and the central olfactory structures, we investigated olfaction in a population of patients with autoimmune encephalitis (AE). METHODS: Nineteen adult subjects (14 males, median age 64 years) diagnosed with definite (14/19) or possible (5/19) AE and followed for ≥ 6 months were enrolled. The Brief Smell Identification Test (B-SIT), a 12-item, forced-choice, scratch-and-sniff measure, was used to assess the patients' olfactory function in comparison with a group of sex- and age-matched healthy controls (HC). According to the B-SIT score, subjects were classified as anosmic (< 6), hyposmic (6-8) and normal (≥ 9). Electro-clinical, laboratory and neuroimaging findings were reviewed. RESULTS: Smell impairment was revealed in 15/19 patients (9 hyposmic, 6 anosmic), compared with 5/19 HC (p = 0.0029). Age, gender and smoking habits did not affect the participants' performance at B-SIT. Olfactory dysfunction appeared more common among patients with definite AE (p = 0.0374), regardless of autoantibody status. Subjects with higher modified Rankin Scale (mRS) scores at AE onset more likely presented hyposmia/anosmia (p = 0.033), and so did those with bilateral ictal/interictal EEG abnormalities (p = 0.006). CONCLUSIONS: We found olfaction to be impaired in a significantly large proportion of AE cases. Smell deficits appeared more common in subjects with severe AE (as indicated by both definite diagnosis and higher mRS score), and might represent an additional feature of immune-mediated encephalitis.

Autoimmune Encephalitis After SARS-CoV-2 Infection: Case Frequency, Findings, and Outcomes.

BACKGROUND AND OBJECTIVES: Autoimmune encephalitis (AE) cases after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, but the frequency is unknown. We aimed to determine the frequency and diagnostic features of coronavirus disease 2019 (COVID-19)-related AE. METHODS: Residual sera from 556 consecutive Mayo Clinic Rochester patients (laboratory cohort) who underwent autoimmune encephalopathy neural immunoglobulin G (IgG) evaluation were tested for total antibodies against the SARS-CoV-2 spike glycoprotein using a Food and Drug Administration-authorized chemiluminescence assay (October 2019-December 2020). Clinical records from patients with a positive SARS-CoV-2 antibody result and available research consent were reviewed. This laboratory cohort was cross-referenced with the Department of Neurology's COVID-19-related consultative experience (encephalopathy cohort, n = 31). RESULTS: Eighteen of the laboratory cohort (3%) were SARS-CoV-2 antibody positive (April-December 2020). Diagnoses were as follows: AE, 2; postacute sequelae of SARS CoV-2 infection (PASC), 3; toxic-metabolic encephalopathy during COVID-19 pneumonia, 2; diverse non-COVID-19 relatable neurologic diagnoses, 9; unavailable, 2. Five of the encephalopathy cohort had AE (16%, including the 2 laboratory cohort cases that overlapped), representing 0.05% of 10,384 patients diagnosed and cared for with any COVID-19 illness at Mayo Clinic Rochester in 2020. The 5 patients met definite (n = 1), probable (n = 1), or possible (n = 3) AE diagnostic criteria; median symptom onset age was 61 years (range, 46-63); 3 were women. All 5 were neural IgG negative and 4 tested were SARS-CoV-2 PCR/IgG index negative in CSF. Phenotypes (and accompanying MRI and EEG findings) were diverse (delirium [n = 5], seizures [n = 2], rhombencephalitis [n = 1], aphasia [n = 1], and ataxia [n = 1]). No acute disseminated encephalomyelitis cases were encountered. The 3 patients with possible AE had spontaneously resolving syndromes. One with definite limbic encephalitis was immune therapy responsive but had residual mood and memory problems. One patient with probable autoimmune rhombencephalitis died despite immune therapy. The remaining 26 encephalopathy cohort patients had toxic-metabolic diagnoses. DISCUSSION: We encountered occasional cases of AE in our 2020 COVID-19 experience. Consistent with sporadic reports and small case series during the COVID-19 pandemic, and prior experience of postinfectious AE, our cases had diverse clinical presentations and were neural IgG and CSF viral particle negative. Application of diagnostic criteria assists in differentiation of AE from toxic-metabolic causes arising in the setting of systemic infection.

COVID-19-associated encephalitis or Creutzfeldt-Jakob disease: a case report.

Background: Accurate diagnosis and management of patients with rapidly progressive dementia may be challenging during the COVID-19 pandemic, which has negatively influenced the diagnostic performances, medical resource allocation and routine care for all non-COVID-19 diseases. Case presentation: We herein present a case of a 57-year-old male with rapidly progressive cognitive decline, headache, diplopia, myalgia, unsteady gait, aggression, depression, insomnia, hallucinations and delusions of persecution. COVID-19-associated encephalitis was briefly considered as a differential diagnosis. However, this hypothesis was rejected upon further investigation. A final diagnosis of sporadic Creutzfeldt-Jakob disease was made. Conclusion: A timely and accurate diagnosis of Creutzfeldt-Jakob disease gives patients and their families the chance to receive a good standard of healthcare and avoid extensive evaluations for other conditions.

Immune-mediated neurological syndrome in SARS-CoV-2 infection: a review of literature on autoimmune encephalitis in COVID-19.

INTRODUCTION: The novel Coronavirus Disease 2019 (COVID-19) is an infection caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) which has been spreading rapidly amongst humans and causing a global pandemic. The notorious infection has shown to cause a wide spectrum of neurological syndrome, including autoimmune encephalitis. OBJECTIVE: Here, we systematically review the literature on autoimmune encephalitis that developed in the background of SARS-CoV-2 infections and also the possible pathophysiological mechanisms of auto-immune mediated damage to the nervous system. METHODOLOGY: An exhaustive search was made in Medline/PubMed, Embase, Scopus and other medical databases, and 28 relevant published articles were selected according to the strict inclusion criteria. RESULTS: Autoimmune encephalitis can occur via three possible proposed pathophysiological mechanism and can manifest during or after the acute infection period. It is more common in adult but can also occur in the paediatric patients. There were various spectra of autoantibody panels reported including antineuronal antibody, anti-gangliosides antibody and onconeural antibody. Majority of the patients responded well to the immunomodulating therapy and achieved good recovery. CONCLUSION: In conclusion, SARSCoV-2 infection can induce various spectrum of autoimmune encephalitis. It is a major concern since there is very limited long-term study on the topic. Hence, this review aims to elucidate on the potential long-term complication of SARS-CoV-2 infection and hopefully to improve the management and prognosis of COVID-19.

Unraveling the enigma of new-onset refractory status epilepticus: a systematic review of aetiologies.

BACKGROUND AND PURPOSE: New-onset refractory status epilepticus (NORSE) is a clinical presentation, neither a specific diagnosis nor a clinical entity. It refers to a patient without active epilepsy or other pre-existing relevant neurological disorder, with a NORSE without a clear acute or active structural, toxic or metabolic cause. This study reviews the currently available evidence about the aetiology of patients presenting with NORSE and NORSE-related conditions. METHODS: A systematic search was carried out for clinical trials, observational studies, case series and case reports including patients who presented with NORSE, febrile-infection-related epilepsy syndrome or the infantile hemiconvulsion-hemiplegia and epilepsy syndrome. RESULTS: Four hundred and fifty records were initially identified, of which 197 were included in the review. The selected studies were retrospective case-control (n = 11), case series (n = 83) and case reports (n = 103) and overall described 1334 patients both of paediatric and adult age. Aetiology remains unexplained in about half of the cases, representing the so-called 'cryptogenic NORSE'. Amongst adult patients without cryptogenic NORSE, the most often identified cause is autoimmune encephalitis, either non-paraneoplastic or paraneoplastic. Infections are the prevalent aetiology of paediatric non-cryptogenic NORSE. Genetic and congenital disorders can have a causative role in NORSE, and toxic, vascular and degenerative conditions have also been described. CONCLUSIONS: Far from being a unitary condition, NORSE is a heterogeneous and clinically challenging presentation. The development and dissemination of protocols and guidelines to standardize diagnostic work-up and guide therapeutic approaches should be implemented. Global cooperation and multicentre research represent priorities to improve the understanding of NORSE.

COVID-19 Associated With Encephalitis: Case Report and Review of Literature.

INTRODUCTION: Neurological problems may be part of severe and early course of coronavirus disease 2019 (COVID-19). COVID-19 associated encephalitis as an evident etiology of altered consciousness has been rarely reported in the literature. CASE REPORT: A case of 66-year-old female presented with classic COVID-19 symptoms and associated diabetic ketoacidosis. Although diabetic ketoacidosis was managed, the patient had persistent impaired level of consciousness with recurrent attacks of left focal fits because of COVID-19-associated encephalitis. However, the patient has markedly improved after recovering from COVID-19. CONCLUSION: Neurologists should be involved in the evaluation and management of COVID-19 patients who present with associated neurological problems.

MOG antibody-associated encephalitis secondary to Covid-19: case report.

BACKGROUND: While Covid-19 predominantly affects the respiratory system, neurological manifestations including encephalitis occur in some patients, possibly affecting the course and outcome of the disease. Here, we describe a unique case of a young man with Covid-19 and transient MOG-positive encephalitis, with a benign course. CASE PRESENTATION: A 22-year-old male, with PCR confirmed Covid-19 infection was admitted because of persistent headache. The clinical examination was normal. Neuropsychological testing revealed distinct executive deficits. Brain MRI and cerebrospinal fluid (CSF) analysis were suggestive for encephalitis. Further laboratory examination revealed a serum MOG antibody titre. The headache improved with analgetic treatment and i.v. methylprednisolone. Consequently, the MOG antibody titer decreased and MRI lesions were resolving. The patient made a full recovery, with no signs of deterioration over the following months. CONCLUSIONS: Covid-19 manifestations in the CNS include encephalitis with variable course and prognosis. This case highlights a possible association between inflammation due to COVID-19 and transient secondary autoimmunity with transient MOG antibodies and atypical clinical presentation.

Delayed presentation of postinfectious encephalitis associated with SARS-CoV-2 infection: a case report.

Neurological manifestations of SARS-CoV-2 are increasingly being recognised and can arise as a result of direct viral invasion, para-infectious or postinfectious immune mechanisms. We report a delayed presentation of COVID-19 postinfectious immune-mediated encephalitis and status epilepticus occurring in a 47-year-old woman 4 weeks after SARS-CoV-2 pulmonary disease. SARS-CoV-2-specific IgG and IgM antibodies were detected in her cerebrospinal fluid with features of encephalitis evident in both magnetic resonance imaging of the brain and electroencephalogram. She made a complete recovery following treatment with high-dose intravenous corticosteroids and intravenous immunoglobulins. Diagnosis of COVID-19 postinfectious encephalitis may prove challenging in patients presenting many weeks following the initial infection. A high index of clinical suspicion and testing intrathecal SARS-CoV-2-specific antibodies are key to its diagnosis. Early immunotherapy is likely to result in a good outcome.

Autoimmune Encephalitis Concomitant with SARS-CoV-2 Infection: Insight from 18F-FDG PET Imaging and Neuronal Autoantibodies.

We report the case of a 72-y-old man with concomitant autoimmune encephalitis and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The patient presented with subacute cerebellar syndrome and myoclonus several days after general infectious symptoms began. Methods: Clinical examination, CT, PET, MRI, and autoantibody testing were performed. Results: The oropharyngeal swab test was positive for SARS-CoV-2. The brain MRI results were normal. Cerebrospinal fluid testing showed normal cell counts, a negative result on reverse-transcription polymerase chain reaction testing, and no oligoclonal banding. Brain 18F-FDG PET showed diffuse cortical hypometabolism associated with putaminal and cerebellum hypermetabolism, compatible with encephalitis and especially cerebellitis. The immunologic study revealed high titers of IgG autoantibodies in serum and cerebrospinal fluid directed against the nuclei of Purkinje cells, striatal neurons, and hippocampal neurons. Whole-body 18F-FDG PET and CT scans did not show neoplasia. Treatment with steroids allowed a rapid improvement in symptoms. Conclusion: This clinical case argues for a possible relationship between SARS-CoV-2 infection and autoimmune encephalitis and for the use of 18F-FDG PET in such a context.

Bickerstaff's brainstem encephalitis associated with anti-GM1 and anti-GD1a antibodies.

Bickerstaff's brainstem encephalitis (BBE) is a Guillain-Barré syndrome (GBS) spectrum disorder associated with predominantly central nervous system predilection. Patients exhibit a variable constellation of depressed consciousness, bilateral external ophthalmoplegia, ataxia and long tract signs. Although the pathophysiology is not fully understood, it has been associated with anti-GQ1b antibodies in two-thirds of patients. We present a patient with clinical features consistent with BBE and positive anti-GM1 and anti-GD1a antibodies. A diagnostic approach to the acutely unwell patient with brainstem encephalitis is explored in this clinical context with a literature review of the aforementioned ganglioside antibody significance. Intravenous immunoglobulin therapy is highlighted in BBE using up-to-date evidence-based extrapolation from GBS.