Acute Demyelinating Disorders of the Central Nervous System

Acute demyelinating disorders of the central nervous system constitute a heterogeneous group of immune-mediated conditions characterised by rapid loss of the myelin sheath enveloping neuronal axons. They encompass syndromes such as acute disseminated encephalomyelitis (ADEM), clinically isolated syndrome (CIS), neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease. Clinically, these disorders present with sudden onset of multifocal neurological deficits—often in combination with encephalopathy—and frequently follow an antecedent infection or immunisation. Magnetic resonance imaging typically reveals patchy or confluent white matter lesions, with variable involvement of deep grey matter, brainstem and spinal cord. Early immunomodulatory interventions, including high-dose corticosteroids, plasmapheresis or intravenous immunoglobulins, are effective in limiting acute injury, yet a substantial proportion of patients experience persistent motor, sensory or cognitive impairments. Prognosis is influenced by clinical phenotype, serological biomarkers and radiological patterns, guiding the use of long-term disease-modifying therapies in relapsing cases. Ongoing research seeks to elucidate underlying pathophysiology, refine diagnostic criteria and develop therapies that promote remyelination and neuroprotection.

Research from Nature Portfolio

Recent studies have mapped the diagnostic pathway in paediatric acute disseminated encephalomyelitis, revealing a median delay of nine days from symptom onset to formal diagnosis, predominantly due to initial misclassification as common infection or aseptic meningitis. Analyses identified later emergence of specific neurological features as a principal factor prolonging physician delay. These insights delineate a unique diagnostic odyssey in ADEM and highlight clinical risk factors amenable to targeted educational interventions aimed at expediting early recognition and treatment.

Acute Demyelinating Disorders of the Central Nervous System publication trend

The graph below shows the total number of articles in acute demyelinating disorders of the central nervous system across all publications each year (not limited to Nature Index journals).

Technical terms

Demyelination: Loss or damage of the myelin sheath surrounding nerve fibres, impairing electrical conduction.

Acute disseminated encephalomyelitis (ADEM): A monophasic, immune-mediated demyelinating disorder of the central nervous system, often following infection or vaccination.

Clinically isolated syndrome (CIS): A first episode of neurological symptoms caused by inflammation or demyelination, suggestive of multiple sclerosis but not fulfilling diagnostic criteria for relapse.

Neuromyelitis optica spectrum disorder (NMOSD): An autoimmune demyelinating condition targeting the optic nerves and spinal cord, frequently associated with aquaporin-4 autoantibodies.

Myelin oligodendrocyte glycoprotein antibody (MOG-Ab): Autoantibodies directed against a myelin constituent, defining a subset of demyelinating syndromes with distinct clinical features.

Evoked potentials (EPs): Neurophysiological tests measuring the electrical response of the nervous system to sensory stimuli, used to detect subclinical demyelination.

References

1. Diagnostic odyssey of acute disseminated encephalomyelitis in children. Scientific Reports (2021).
2. Clinical Presentation and Outcomes of Acute Disseminated Encephalomyelitis in Adults Worldwide: Systematic Review and Meta-Analysis. Frontiers in Immunology (2022).
3. Multimodal evoked potentials are useful for the diagnosis of pediatric acute disseminated encephalomyelitis. BMC Pediatrics (2024).
4. Management of pediatric post-infectious neurological syndromes. Italian Journal of Pediatrics (2021).