Acute disseminated encephalomyelitis and transverse myelitis following COVID-19 vaccination - A self-controlled case series analysis.

Acute Disseminated Encephalomyelitis (ADEM) and Transverse Myelitis (TM) are within the group of immune mediated disorders of acquired demyelinating syndromes. Both have been described in temporal association following various vaccinations in case reports and case series and have been evaluated in observational studies. A recent analysis conducted by The Global Vaccine Data Network (GVDN) observed an excess of ADEM and TM cases following the adenoviral vectored ChAdOx1 nCoV-19 (AZD1222) and mRNA-1273 vaccines, compared with historically expected background rates from prior to the pandemic. Further epidemiologic studies were recommended to explore these potential associations. We utilized an Australian vaccine datalink, Vaccine Safety Health-Link (VSHL), to perform a self-controlled case series analysis for this purpose. VSHL was selected for this analysis as while VSHL data are utilised for GVDN association studies, they were not included in the GVDN observed expected analyses. The VSHL dataset contains vaccination records sourced from the Australian Immunisation Register, and hospital admission records from the Victorian Admitted Episodes Dataset for 6.7 million people. These datasets were used to determine the relative incidence (RI) of G040 (ADEM) and G373 (TM) ICD-10-AM coded admissions in the 42-day risk window following COVID-19 vaccinations as compared to control periods either side of the risk window. We observed associations between ChAdOx1 adenovirus vector COVID-19 vaccination and ADEM (all dose RI: 3.74 [95 %CI 1.02,13.70]) and TM (dose 1 RI: 2.49 [95 %CI: 1.07,5.79]) incident admissions. No associations were observed between mRNA COVID-19 vaccines and ADEM or TM. These findings translate to an extremely small absolute risk of ADEM (0.78 per million doses) and TM (1.82 per million doses) following vaccination; any potential risk of ADEM or TM should be weighed against the well-established protective benefits of vaccination against COVID-19 disease and its complications. This study demonstrates the value of the GVDN collaboration leveraging large population sizes to examine important vaccine safety questions regarding rare outcomes, as well as the value of linked population level datasets, such as VSHL, to rapidly explore associations that are identified.

The risk of acute disseminated encephalomyelitis (ADEM) following covid-19 vaccination in England: A self-controlled case-series analysis.

Acute disseminated encephalomyelitis (ADEM) has been identified as an Adverse Event of Special Interest in the COVID-19 vaccine programme due to its long-standing temporal association with a wide range of other vaccines. Case reports of ADEM shortly following COVID-19 vaccination have now been documented. There were 217 ADEM admissions in 215 individuals in the period 8th December 2020 to 31st March 2023. An increased risk of ADEM following the first dose of ChAdOx1 vaccine was observed (relative incidence (RI) = 3.13, 95% Confidence Interval (CI) [1.56-6.25]) with a vaccine attributable risk of 0.39 per million doses. When doses 1 and 2 were combined this increased risk remained just significant (1.96 [95%CI 1.01-3.82]). No significant increased risk was observed with any other vaccine or dose. This small, elevated risk after the first dose of ChAdOx1-S vaccine demonstrates how large national electronic datasets can be used to identify very rare risks and provides reassurance that any risk of ADEM following the ChAdOx1-S COVID-19 vaccination is extremely small. Given the rarity of this risk, further studies in settings with access to data on large populations should be carried out to verify these findings.

Acute encephalomyelitis in a 52-year-old male post messenger ribonucleic acid severe acute respiratory syndrome coronavirus 2 vaccination: a case report.

BACKGROUND: Acute disseminated encephalomyelitis is a well-known, but rare, side effect of some vaccines, or symptom following a febrile illness. CASE: A 69-year-old, otherwise healthy Hispanic male presented with acute fever, confusion, and later progressive weakness after receiving the first dose of the mRNA-1273 (Moderna) severe acute respiratory syndrome coronavirus 2 vaccine. Considering the progressive deterioration of the patient, despite being on multiple immunosuppressive agents, a brain biopsy was obtained, which revealed nonspecific meningoencephalitis. CONCLUSION: In this case, we highlight the need for a regulatory framework to assist clinicians and patients with coverage of treatment for acute disseminated encephalomyelitis. The use of intravenous immunoglobulin in conjunction with glucocorticoids seems to be an effective treatment option.

Neurological sequelae of vaccines.

IMPORTANCE: Vaccines are a safe and efficacious way to prevent a variety of infectious diseases. Over the course of their existence, vaccines have prevented immeasurable morbidity and mortality in humans. Typical symptoms of systemic immune activation are common after vaccines and may include local soreness, myalgias, nausea, and malaise. In the vast majority of cases, the severity of the infectious disease outweighs the risk of mild adverse reactions to vaccines. Rarely, vaccines may be associated with neurological sequela that ranges in severity from headache to transverse myelitis, acute disseminated encephalomyelitis, and Guillain-Barre syndrome (GBS). Often, a causal link cannot be confirmed, and it remains unclear if disease onset is directly related to a recent vaccination. OBSERVATIONS: This review serves to summarize reported neurologic sequelae of commonly used vaccines. It will also serve to discuss potential pathogenesis. It is important to note that many adverse events or reactions to vaccines are self-reported into databases, and causal proof cannot be obtained. CONCLUSIONS AND RELEVANCE: Recognition of reported adverse effects of vaccines plays an important role in public health and education. Early identification of these symptoms can allow for rapid diagnosis and potential treatment. Vaccines are a safe option for prevention of infectious diseases.

Association between seasonal influenza vaccines and the increased risk of acute disseminated encephalomyelitis, estimated using the Vaccine Adverse Event Reporting System.

Acute disseminated encephalomyelitis (ADEM) is a rare and immune-mediated inflammatory disorder of the central nervous system (CNS) that can be triggered by infections and vaccinations. To date, only anecdotal case studies have reported the association between ADEM incidence and seasonal influenza vaccines, and multiple studies have found no association. This study aimed to investigate the association between the incidence of ADEM and seasonal influenza vaccines in a real-world setting using data from the United States Vaccine Adverse Event Reporting System (VAERS). Further, propensity score matching and disproportionality analysis was performed by calculating the adjusted reporting odds ratio (ROR) of reported ADEM cases associated with seasonal influenza vaccines using multiple logistic regression. Additionally, we analysed the time-to-onset using Weibull shape parameters (WSPs). The VAERS database contained 390,352 adverse events reported from January 2011 to December 2020. The ROR of seasonal influenza vaccines for ADEM was 3.02 (95% confidence interval: 1.72-5.33). The median duration (interquartile range) of ADEM was 11.0 (5.0-33.0) days. The median duration of ADEM induced by egg culture-based influenza vaccine (Egg-based vaccine) and cell culture-based influenza vaccine (Cell-based vaccine) was 10.0 (5.0-24.0) and 91.0 (79.0-125.0) days (P < 0.001), respectively. Only Cell-based cases had WSP ß > 1, indicating a wear-out failure type. The incidence of ADEM within 30 days after administration of egg- and Cell-based vaccines was 78.6% and 0.0%, respectively. Our findings indicate that ADEM incidence is associated with seasonal influenza vaccines; thus, careful monitoring of ADEM is required within the first month of Egg-based vaccination and after two months of Cell-based vaccination. Neurologists and general practitioners should exercise caution, as the timing for careful monitoring varies depending on the vaccine type.

Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance.

BACKGROUND: Background incidence rates are critical in pharmacovigilance to facilitate identification of vaccine safety signals. We estimated background incidence rates of 11 adverse events of special interest related to COVID-19 vaccines in Ontario, Canada. METHODS: We conducted a population-based retrospective observational study using linked health administrative databases for hospitalizations and emergency department visits among Ontario residents. We estimated incidence rates of Bell's palsy, idiopathic thrombocytopenia, febrile convulsions, acute disseminated encephalomyelitis, myocarditis, pericarditis, Kawasaki disease, Guillain-Barré syndrome, transverse myelitis, acute myocardial infarction, and anaphylaxis during five pre-pandemic years (2015-2019) and 2020. RESULTS: The average annual population was 14 million across all age groups with 51% female. The pre-pandemic mean annual rates per 100,000 population during 2015-2019 were 191 for acute myocardial infarction, 43.9 for idiopathic thrombocytopenia, 28.8 for anaphylaxis, 27.8 for Bell's palsy, 25.0 for febrile convulsions, 22.8 for acute disseminated encephalomyelitis, 11.3 for myocarditis/pericarditis, 8.7 for pericarditis, 2.9 for myocarditis, 2.0 for Kawasaki disease, 1.9 for Guillain-Barré syndrome, and 1.7 for transverse myelitis. Females had higher rates of acute disseminated encephalomyelitis, transverse myelitis and anaphylaxis while males had higher rates of myocarditis, pericarditis, and Guillain-Barré syndrome. Bell's palsy, acute disseminated encephalomyelitis, and Guillain-Barré syndrome increased with age. The mean rates of myocarditis and/or pericarditis increased with age up to 79 years; males had higher rates than females: from 12 to 59 years for myocarditis and ≥12 years for pericarditis. Febrile convulsions and Kawasaki disease were predominantly childhood diseases and generally decreased with age. CONCLUSIONS: Our estimated background rates will permit estimating numbers of expected events for these conditions and facilitate detection of potential safety signals following COVID-19 vaccination.

Post COVID-19 Vaccination Acute Disseminated Encephalomyelitis: A Case Report.

INTRODUCTION: A 67-year-old female with no significant past medical history presented to the critical care department with symptoms of encephalopathy. CASE PRESENTATION: The patient's Main Concerns and the Important Clinical Findings: The patient had a history of COVID -19 vaccination (recombinant ChAdOX1 nCoV-19) 14 days prior to the symptoms. She underwent an MRI of the brain and cervical spine and a lumbar puncture. The Primary Diagnoses, Interventions, and Outcomes: The patient was examined and sent for an MRI of the brain and cervical spine, followed by extensive blood and CSF investigations to rule out any infective, paraneoplastic, connective tissue disorder, or inflammatory disorder. The patient was given steroids, and a good response was reported. The primary diagnosis was made as vaccine-induced ADEM. CONCLUSION: The clinical exam, location, sparse contrast enhancement, and CSF findings were all consistent with an acute demyelinating event, and the history of vaccination, together with the clinical situation, was found to be favourable for the development of acute disseminated encephalomyelitis.

ADEM after ChAdOx1 nCoV-19 vaccine: A case report.

Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease of the central nervous system (CNS), clinically defined by an acute polyfocal neurological syndrome usually with monophasic course. ADEM often occurs after infections, but 5%-10% of cases are preceded by vaccinations. Several cases of ADEM have been described after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, whereas no case has been reported after adenovirus-vectored or mRNA COVID-19 vaccine administration. Here we describe a case of ADEM presenting 2 weeks after receiving the first dose of ChAdOx1 nCoV-19 vaccine. Patient clinical/magnetic resonance imaging (MRI) status spontaneously improved and rapidly resolved with corticosteroids. A 4-month follow-up showed complete recovery and no relapses.

Acute disseminated encephalomyelitis in a patient vaccinated against SARS-CoV-2.

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease, and there are some data that link this event with various vaccinations. We report a young female admitted to the hospital with headache, fever, back pain, nausea, vomiting, and urinary retention. Two weeks prior, she received the first dose of SARS-CoV-2 mRNA vaccine. Brain and spinal cord magnetic resonance imaging (MRI) showed distinctive for ADEM widespread demyelinating lesions. The patient was successfully treated with methylprednisolone.

Postvaccinal Encephalitis after ChAdOx1 nCov-19.

The global SARS-CoV-2 pandemic has contributed to more than 163 million confirmed infections and 3.3 million deaths worldwide. The severity of the pandemic has led to an unprecedented effort to develop multiple effective vaccines. Due to excellent safety and efficacy data from clinical trials, several vaccines were approved. We report a case series of postvaccinal encephalitis in temporal correlation to vaccination with ChAdOx1 nCov-19. The diagnostic criteria for possible autoimmune encephalitis were fulfilled. Our patients responded well to immunosuppressive therapy with corticosteroids. The incidence has been estimated to be approximately 8 per 10 million vaccine doses. Complication of postvaccinal encephalitis after ChAdOx1 nCoV-19 vaccination still appear to be very rare, but need to be diagnosed and treated adequately. Large pooled data from observational epidemiologic studies are necessary to verify causality. ANN NEUROL 2021;90:506-511.

Vaccination-associated acute disseminated encephalomyelitis.

While the basic definition of vaccination-associated acute disseminated encephalomyelitis (ADEM) is relatively clear and easily understandable, it is often difficult to diagnose ADEM based on clinical findings alone. ADEM is actually a heterogeneous clinical syndrome that can be approximately characterized by encephalomyelitis with multiple inflammatory demyelination, autoimmune causes, and relationship with a preceding infection or vaccination. The differential diagnosis of ADEM should exclude the possibility of infectious or other autoimmune encephalitis. The occurrence of vaccination-associated ADEM is influenced by several factors including the health and ethnic status of the vaccinated individual, vaccine components, and environment. Cases suspected of vaccination-associated ADEM should be analyzed cautiously from multi-disciplinary perspectives.

Unusual case of cerebral demyelination and bilateral optic neuritis in an infant with suppurative BCG lymphadenitis.

Cerebral demyelination and optic neuritis are often seen in children with acute disseminated encephalomyelitis following various infections and immunisations. An eight month old girl presented with a left axillary lymph node swelling and an erythematous lace-like rash over her cheeks and trunk. She then developed acute encephalopathy, bilateral nystagmus, right hemiparesis and left facial nerve palsy. Her electroencephalogram showed an encephalopathic process and visual evoked response study were grossly abnormal. Her MRI brain showed hyperintensities in the midbrain, pons and bilateral cerebellar peduncles. She was treated as postinfectious cerebral demyelination with intravenous antibiotics, methylprednisolone and immunoglobulin. Left axillary lymph node excision biopsy and GeneXpert test detected Mycobacterium tuberculosis complex that prompted initiation of antituberculous therapy. Her chest X-ray and cerebrospinal fluid examinations for tuberculosis were normal. She showed significant recovery after 2 weeks. This case illustrates a rare presentation of cerebral demyelination and bilateral optic neuritis following suppurative BCG lymphadenitis.

Vaccines and the risk of acute disseminated encephalomyelitis.

BACKGROUND: It is important to examine the risk of Acute disseminated encephalomyelitis (ADEM) after vaccination. METHODS: We conducted a nested case-control study between January 2011 and December 2015. Four controls per case were matched for age, gender, address. An independent expert committee validated the diagnoses of cases and controls. Data on vaccinations were obtained from computerized vaccination records. The analyses were conducted with the use of conditional logistic regression. RESULTS: The analyses include 272 cases of ADEM and 1096 controls. No increase in the risk of ADEM was observed for vaccination against hepatitis B, influenza, polio(live), diphtheria, pertuss(acellular), tetanusis, measles, mumps, rubella, Japanese Encephalitis, meningitis, hepatitis A, varicella and rabies vaccines. Vaccine was associated with a statistically significant increase in risk in the 31-60-day exposure interval (OR, 4.04 [95% CI, 1.07-12.69]), but not the 0-30 and 61-180-day interval. There was no association between vaccine received and the recurrence of ADEM. CONCLUSIONS: Findings from the present study do not demonstrate an association of vaccines with an increased risk of ADEM and its recurrence among either paediatric (≤18 years) or adult (>18 years) individuals within the 180 days after vaccinations. The finding in children in the 31-60 day risk interval is likely coincidental and was not confirmed in separate self-control analyses.

Lethal high: acute disseminated encephalomyelitis (ADEM) triggered by toxic effect of synthetic cannabinoid black mamba.

A previously well 25-year-old man presented with agitation, double incontinence and left-sided incoordination. His symptoms started after smoking a synthetic cannabinoid (black mamba) 5 days earlier. Over 48 hours, he developed aphasia, generalised hypertonia, hyper-reflexia and dense left hemiparesis. This progressed to profuse diaphoresis, fever, tachycardia, hypertension and a possible seizure necessitating admission to the intensive care unit. CT head and cerebrospinal fluid analysis were unremarkable. MRI brain demonstrated asymmetric multifocal hyperintense lesions in white and grey matter, which raised suspicions of acute disseminated encephalomyelitis (ADEM). An electroencephalogram showed widespread brain wave slowing, indicating diffuse cerebral dysfunction. Cerebral angiogram was normal. Toxicology analysis of the substance confirmed a potent synthetic cannabinoid NM2201, technically legal at the time. The patient made a slow but significant recovery after a course of intravenous methylprednisolone, intravenous immunoglobulins and oral steroids, and was later transferred to a rehabilitation bed.

Acute Disseminated Encephalomyelitis After Influenza Vaccination: A Case Report.

Acute disseminated encephalomyelitis is an inflammatory demyelinating disease of the central nervous system that has been associated with influenza immunization, but only a few cases related to vaccination for influenza have been reported. Acute disseminated encephalomyelitis developed in a 42-year-old woman within 3 weeks of receiving the seasonal influenza vaccine. She had 80% recovery after 3 months of treatment with methylprednisolone. Although cases of acute disseminated encephalomyelitis after vaccination for influenza are rare, enough of them have occurred that critical care nurses should be aware of the possibility. Early treatment can prevent serious residual signs and symptoms; therefore, correct and quick diagnosis is important. Medical history obtained from patients with central nervous system problems should include history of recent vaccinations.

A Case Report of Post Rabipur (Purified Chick Embryo Rabies Vaccine) Acute Disseminated Encephalomyelitis.

Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease that typically occurs following a viral infection or vaccination. The incidence of ADEM following vaccination has become very low since introduction of non-neural rabies vaccine and only few cases had been reported due to pure chick embryo derived rabies vaccine (PCERV). Here we are reporting a rare case of delayed post vaccinal ADEM.

[Acute disseminated encephalomyelitis after rabies vaccination: a case report]. / Encéphalomyélite aiguë disséminée post-vaccination antirabique: à propos d'un cas.

Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease of the central nervous system. It is a disease whose incidence is not precisely known. The presumed mechanism is demyelination of the immune-mediated central nervous system. There is no pathognomonic clinical presentation in ADEM. The combination of multifocal neurological disorders arising in the aftermath of an infection or vaccination should alert the clinician. We report a case of ADEM in an 8-year-old child occurring after antirabies vaccination. The diagnosis was made by nuclear magnetic resonance imaging (bilateral and multifocal lesions in the subcortical occipitoparietal and frontal left anterior white matter with involvement of U fibers) and a history of antirabies vaccination. The clinical course was marked by the appearance of motor and visual effects.

Influenza vaccine-induced CNS demyelination in a 50-year-old male.

PATIENT: Male, 50. FINAL DIAGNOSIS: Acute post-vaccination CNS demyelinating disorder. SYMPTOMS: Blurred vision • hemiparesis • hemiplegia • hypertonia • itching • paresthesia. MEDICATION: -. CLINICAL PROCEDURE: MRI. SPECIALTY: Neurology. OBJECTIVE: Rare disease. BACKGROUND: There are several categories of primary inflammatory demyelinating disorders, which comprise clinically similar neurologic sequelae. Of interest, clinically isolated syndrome (CIS) and acute disseminated encephalomyelitis (ADEM) are 2 demyelinating conditions of the central nervous system (CNS), whose clinical similarity pose a significant challenge to definitive diagnosis. Yet, both remain important clinical considerations in patients with neurologic signs and symptoms in the context of recent vaccination. CASE REPORT: We report a case of a 50-year-old Caucasian male with a course of progressive, focal, neurologic deficits within 24 h after receiving the influenza vaccine. Subsequent work-up revealed the possibility of an acute central nervous system (CNS) demyelinating episode secondary to the influenza vaccine, best described as either CIS or ADEM. CONCLUSIONS: Case reports of CNS demyelination following vaccinations have been previously noted, most often occurring in the context of recent influenza vaccination. This report serves to document a case of CNS demyelination occurring 24 h after influenza vaccination in a middle-aged patient, and will describe some salient features regarding the differential diagnosis of CIS and ADEM, as well as their potential management.