Clinical Presentation and Outcomes of Acute Disseminated Encephalomyelitis in Adults Worldwide: Systematic Review and Meta-Analysis

Adult Onset Acute Disseminated Encephalomyelitis: A Case Report

Acute disseminated encephalomyelitis (ADEM) is a rare autoimmune demyelinating disorder of the central nervous system that can mimic other neurological diseases, such as multiple sclerosis. ADEM is thought to manifest in the presence of environmental triggers, namely viral or bacterial infections, with multiple simultaneous neurological deficits, frequently accompanied by encephalopathy. Here, we report the case of a 49-year-old female patient who presented in the emergency department with encephalopathy, right-side muscle weakness, dizziness, vertigo, ataxia, and postural imbalance, preceded by symptoms suggesting recent pharyngitis/sialadenitis three weeks prior. Cerebrospinal fluid analysis revealed lymphocytic pleocytosis, elevated protein levels, normal glucose levels, no oligoclonal bands, and culture and viral studies were negative. After a normal cerebral computed tomography, brain and cervical spine magnetic resonance imaging (MRI) revealed multiple, T2-weighted hyperintense supratentorial and infratentorial white matter lesions, including the right cerebellar peduncle and posterior limb of the left internal capsule. The diagnosis of ADEM was made, and the patient was treated with high-dose intravenous glucocorticoids followed by oral tapering with clinical improvement. During follow-up, the control MRI was compatible with the diagnosis. This case illustrates the diagnostic approach of a patient presenting with subacute neurological deficits and the importance of contemplating possible differential diagnoses and swiftly initiating treatment.

Acute necrotizing encephalopathy in adult patients with influenza: a case report and review of the literature

The neurological complications of influenza affect mainly the pediatric Asian population. In the category of influenza-associated encephalopathy, acute necrotizing encephalopathy (ANE) is a rapidly progressive and fulminant brain disorder associated with significant neurological sequelae and mortality. To date, only a few adult cases of influenza-associated ANE have been reported. We describe a 44-year-old woman who presented with rapid progression of consciousness impairment and recurrent generalized convulsions. Influenza was diagnosed three days prior to presentation, and infection with influenza A (H3N2) pdm09 was subsequently confirmed. A diagnosis of ANE was made based on the presence of characteristic brain MRI findings, the exclusion of central nervous system infection, and an elevated serum interleukin-6 level. Pulse steroid therapy followed by tocilizumab was initiated, which led to clinical stabilization and improvement. Genetic testing revealed that the patient carried heterozygous human leukocyte antigen DQB1 03:03 and DRB1 09:01 genotypes. An analysis of the adult cases of influenza-associated ANE in the literature and the present case revealed a wide range of ages (22-71 years), a short interval (median 3 days) between the clinical onset of influenza and ANE, and a high overall mortality rate (32%). The thalamus was the most frequent (91%) location of the lesions. Our report highlights the importance of identifying this devastating but treatable neurological complication of influenza in adults, especially those of Asian descent. As a cytokine storm is the most accepted pathogenic mechanism for ANE, cytokine-directed therapies may be promising treatments for which further investigation is warranted.

Cognitive and psychopathological outcomes in acute disseminated encephalomyelitis

Individuals with acute disseminated encephalomyelitis (ADEM) can experience persistent cognitive deficits and psychopathology, which significantly interferes with daily functioning and quality of life. Here, we review the current literature to characterise the cognitive and psychological sequelae, suggest avenues for further research and discuss the implications for clinical practice. Research on this topic is largely limited to the paediatric population with a few case studies in the adult population. The current evidence demonstrates persistent cognitive deficits in attention and information processing speed, as well as elevated symptoms of depression and anxiety. Results are mixed for executive functions and memory, while language and visuospatial functions are relatively undisturbed. There is emerging evidence to suggest that individuals-particularly children-with ADEM experience persistent cognitive deficits and suffer from elevated symptoms of depression and anxiety. Comprehensive neuropsychological assessments are recommended to guide intervention and monitor progress. Further research is required to clarify our understanding of the cognitive and psychological outcomes following ADEM and the factors that influence them.

Challenges in Diagnosis and Therapeutic Strategies in Late-Onset Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory and degenerative demyelinating disease of the central nervous system of unknown etiology, which affects individuals in their early adulthood. However, nearly 5-10% of people with MS can be diagnosed at ages above 50 years old, referred to as late-onset multiple sclerosis (LOMS). Some studies have reported a distinctive presentation, clinical course, and prognosis for LOMS, implicating a different diagnostic and therapeutic approach for this population. Furthermore, similar manifestations between LOMS and other age-related conditions may lead to potential misdiagnosis and diagnostic delays, and a higher burden of multimorbidity associated with aging can further complicate the clinical picture. This review aims to explore the clinical characteristics, the disease course, and the differential diagnosis of LOMS and addresses therapeutic considerations for this population.

Myelin oligodendrocyte glycoprotein antibody-associated disease with clinical presentation as multiple episodes of isolated meningeal involvement: a case report

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) constitutes a group of autoimmune neuroinflammatory conditions that are characterized by positive serum MOG-immunoglobulin G antibodies. The relationship between MOGAD and immune factors remains unclear. Herein, we report a man in his early 30s who initially presented symptoms of headache and low-grade fever persisting for 20 days. The patient experienced isolated meningitis onset and had recurrent meningitis as the primary clinical feature, which manifested as low-grade fever, headache, and neck rigidity. Although cranial magnetic resonance imaging showed no abnormalities, immunotherapy was promptly administered upon diagnosing MOGAD through positive MOG-specific antibody testing of cerebrospinal and serum fluids. Notably, the patient's symptoms exhibited rapid improvement following treatment. Although meningitis is traditionally associated with infectious diseases, it can also occur in antibody-related autoimmune diseases that affect the central nervous system. Consequently, MOGAD should be considered in cases of aseptic meningitis with an unknown etiology, to facilitate definitive diagnosis and enhance patient prognosis.

Acute Disseminated Encephalomyelitis and Acute Encephalitis Following Vaccination Against SARS-CoV-2: Two Case Reports and Review of Literature

The spectrum of severe neurological complications following COVID-19 vaccination includes cerebrovascular events, inflammatory diseases of the CNS, cranial and peripheral nerve involvement and muscle affections. Post-vaccinal acute disseminated encephalomyelitis (ADEM) and acute encephalitis are rare. We report on a patient suffering from acute encephalitis and another with post-vaccinal monophasic ADEM. Beside imaging features typical for acute autoimmune associated inflammation, cranial MRI disclosed also transient haemorrhagic signal alterations in some cerebral lesions. To our best knowledge, this has not been mentioned before in literature. Competing causes were excluded by extensive laboratory investigations including serial CSF analysis. In line with the literature, repeated iv high-dosage corticosteroid therapy resulted in impressive improvement of neurological symptoms in both patients.