RARE DISEASE
Acute disseminated encephalomyelitis
Acute disseminated encephalomyelitis
Acute disseminated encephalomyelitis
Synonyms: ADEM, Acute disseminated encephalitis
Synonyms: ADEM, Acute disseminated encephalitis
Synonyms: ADEM, Acute disseminated encephalitis
Drug discovery
1
drug
With orphan designation
Overview
Acute Disseminated Encephalomyelitis (ADEM) is an immune-mediated demyelinating disorder of the CNS, typically triggered by infections (50-75% of cases) or vaccinations. It presents with acute encephalopathy, multifocal neurologic deficits, and MRI findings of large, bilateral white matter lesions. Diagnosis requires excluding mimics like multiple sclerosis and infectious encephalitis. First-line treatment involves high-dose corticosteroids, with plasma exchange or IVIG for refractory cases. Most patients recover fully, though 5-25% experience relapses [1][4][7][16].
Therapies
Categories: rare neurological diseases, rare ophthalmic disorders
Research Papers
461 drug discovery papers about Acute disseminated encephalomyelitis, with 3 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
461 drug discovery papers about Acute disseminated encephalomyelitis, with 3 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
2026-07-07 | Myelin oligodendrocyte glycoprotein antibody-related autoimmune encephalitis misdiagnosed as acute cerebral infarction: A case report.
Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory demyelinating autoimmune disorder of the central nervous system that exhibits a broad spectrum of known clinical phenotypes, including optic neuritis, myelitis, acute disseminated encephalomyelitis, encephalitis, meningoencephalitis, and brainstem encephalitis. However, new evidence indicates that a small subset of patients may present with cortical cerebral encephalitis (CCE). When CCE manifests as acute unilateral limb weakness, it may closely mimic acute cerebral infarction (ACI), resulting in misdiagnosis and delayed initiation of immunotherapy. Here, we report a case initially diagnosed as ACI and highlight key diagnostic clues and therapeutic considerations that may help to facilitate earlier recognition and appropriate management. A young woman was admitted with left-sided limb weakness and was initially diagnosed with ACI. The final diagnosis was myelin oligodendrocyte glycoprotein (MOG) antibody-related autoimmune encephalitis, which was established by integrating the clinical presentation, contrast-enhanced brain magnetic resonance imaging (MRI) findings, cerebrospinal fluid (CSF) antibody testing, and systematic exclusion of alternative etiologies. After an initial misdiagnosis, the patient received neuroprotective agents without meaningful improvement. Subsequent lumbar puncture and CSF testing supported the diagnosis of MOG antibody-related autoimmune encephalitis. Treatment was then adjusted to include both high-dose intravenous corticosteroid pulse therapy and immunotherapy, which resulted in marked clinical improvement. The patient's condition remained stable at 2-month follow-up, with no disease progression. Contrast-enhanced MRI showed no abnormalities in the unilateral cerebral cortex. CCE associated with MOGAD may be misdiagnosed as ACI, particularly when focal motor deficits are the predominant presenting feature. Early recognition, prompt diagnostic evaluation, and timely initiation of immunotherapy are crucial for improving clinical outcomes. Greater clinician awareness and improved neuroimaging-based differentiation between ACI and CCE are therefore needed. In patients with stroke-mimicking presentations but atypical imaging findings, contrast-enhanced MRI and cerebrospinal fluid testing for MOG immunoglobulin G should be prioritized. High-dose steroid pulse therapy combined with immunotherapy remains the recommended first-line treatment for suspected MOG antibody-related autoimmune encephalitis.
2026-07-01 | Delayed Myelin Oligodendrocyte Glycoprotein Antibody-Associated Demyelination Five Years After an Acute Disseminated Encephalomyelitis-Like Episode in an Adolescent: A Case Report
Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an immune-mediated inflammatory demyelinating disorder of the central nervous system with a broad pediatric clinical spectrum. Acute disseminated encephalomyelitis (ADEM)-like presentations are more frequent in younger children, whereas older children and adolescents may present with optic neuritis, transverse myelitis, or multifocal central nervous system involvement. We report the case of a 14-year-old male adolescent who developed a severe MOG-IgG-positive demyelinating event five years after an initial ADEM-like episode. At nine years of age, he presented with back pain, gait disturbance, urinary incontinence, mild drowsiness, fever, cerebrospinal fluid pleocytosis, subcortical and medullary brain lesions, and longitudinally extensive myelitis. MOG-IgG testing was not available at that time, and the episode was diagnosed as ADEM based on the overall clinico-radiological presentation, with complete recovery after corticosteroid therapy. Five years later, he presented with fever, acute quadriparesis predominating in the lower limbs, pyramidal signs, and sphincter dysfunction. Brain MRI showed multiple ill-defined subcortical T2-weighted/fluid-attenuated inversion recovery (T2/FLAIR) hyperintense lesions, and spinal MRI demonstrated longitudinally extensive cervical myelitis from the cervicomedullary junction to C6. Cerebrospinal fluid analysis showed marked pleocytosis, elevated protein, absence of oligoclonal bands, and negative infectious studies. Serum MOG-IgG was positive at a titer of 1:100 using a fixed cell-based assay, while AQP4-IgG was negative. He received intravenous methylprednisolone followed by intravenous immunoglobulin because of insufficient initial improvement, with complete clinical recovery at one month and marked radiological regression at six months. This case emphasizes that a confirmed MOG-IgG-positive demyelinating event may occur after a prolonged relapse-free interval following an earlier ADEM-like demyelinating episode, while also underscoring that the first episode should be interpreted cautiously because MOG-IgG testing was unavailable. Long-term follow-up remains essential because short-term clinical and radiological improvement does not establish durable disease control.
2026-06-20 | Suspected Acute Disseminated Encephalomyelitis Presenting With Persistent Vegetative State and Full Neurological Recovery in an Adult: A Case Study
Acute disseminated encephalomyelitis (ADEM) is an autoimmune inflammatory disease of the central nervous system that typically presents with headache, fever, altered consciousness, and seizures. Diagnosis is made clinically and radiologically, supported by the exclusion of mimics. Delayed treatment can lead to severe neurological impairment, including a persistent vegetative state. A 69-year-old Asian female with rheumatic heart disease and prior transverse myelitis presented with hypoxic respiratory failure. On hospital day (HD) 4, she developed a rapid decline in mental status, progressing to a vegetative state with electroclinical seizures. Brain MRI showed diffuse, symmetric T2/fluid-attenuated inversion recovery (FLAIR) hyperintensities involving subcortical white matter, which is an atypical finding for classic ADEM. Extensive infectious and autoimmune testing was unrevealing. Lumbar puncture on HD 11 (prior to steroids) showed no pleocytosis. She remained vegetative for 39 days without response to high-dose corticosteroids. Following a five-day course of intravenous immunoglobulin (IVIG), she showed marked neurological recovery. At discharge, she returned to her baseline functional status. This case illustrates the diagnostic challenges of suspected ADEM in an older adult with atypical symmetric imaging, prolonged vegetative state, and delayed response to immunotherapy. The case adds to the limited literature on extended encephalopathy in suspected ADEM and underscores the role of IVIG when steroid response is unclear.
2026-07-07 | Myelin oligodendrocyte glycoprotein antibody-related autoimmune encephalitis misdiagnosed as acute cerebral infarction: A case report.
Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory demyelinating autoimmune disorder of the central nervous system that exhibits a broad spectrum of known clinical phenotypes, including optic neuritis, myelitis, acute disseminated encephalomyelitis, encephalitis, meningoencephalitis, and brainstem encephalitis. However, new evidence indicates that a small subset of patients may present with cortical cerebral encephalitis (CCE). When CCE manifests as acute unilateral limb weakness, it may closely mimic acute cerebral infarction (ACI), resulting in misdiagnosis and delayed initiation of immunotherapy. Here, we report a case initially diagnosed as ACI and highlight key diagnostic clues and therapeutic considerations that may help to facilitate earlier recognition and appropriate management. A young woman was admitted with left-sided limb weakness and was initially diagnosed with ACI. The final diagnosis was myelin oligodendrocyte glycoprotein (MOG) antibody-related autoimmune encephalitis, which was established by integrating the clinical presentation, contrast-enhanced brain magnetic resonance imaging (MRI) findings, cerebrospinal fluid (CSF) antibody testing, and systematic exclusion of alternative etiologies. After an initial misdiagnosis, the patient received neuroprotective agents without meaningful improvement. Subsequent lumbar puncture and CSF testing supported the diagnosis of MOG antibody-related autoimmune encephalitis. Treatment was then adjusted to include both high-dose intravenous corticosteroid pulse therapy and immunotherapy, which resulted in marked clinical improvement. The patient's condition remained stable at 2-month follow-up, with no disease progression. Contrast-enhanced MRI showed no abnormalities in the unilateral cerebral cortex. CCE associated with MOGAD may be misdiagnosed as ACI, particularly when focal motor deficits are the predominant presenting feature. Early recognition, prompt diagnostic evaluation, and timely initiation of immunotherapy are crucial for improving clinical outcomes. Greater clinician awareness and improved neuroimaging-based differentiation between ACI and CCE are therefore needed. In patients with stroke-mimicking presentations but atypical imaging findings, contrast-enhanced MRI and cerebrospinal fluid testing for MOG immunoglobulin G should be prioritized. High-dose steroid pulse therapy combined with immunotherapy remains the recommended first-line treatment for suspected MOG antibody-related autoimmune encephalitis.
2026-07-01 | Delayed Myelin Oligodendrocyte Glycoprotein Antibody-Associated Demyelination Five Years After an Acute Disseminated Encephalomyelitis-Like Episode in an Adolescent: A Case Report
Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an immune-mediated inflammatory demyelinating disorder of the central nervous system with a broad pediatric clinical spectrum. Acute disseminated encephalomyelitis (ADEM)-like presentations are more frequent in younger children, whereas older children and adolescents may present with optic neuritis, transverse myelitis, or multifocal central nervous system involvement. We report the case of a 14-year-old male adolescent who developed a severe MOG-IgG-positive demyelinating event five years after an initial ADEM-like episode. At nine years of age, he presented with back pain, gait disturbance, urinary incontinence, mild drowsiness, fever, cerebrospinal fluid pleocytosis, subcortical and medullary brain lesions, and longitudinally extensive myelitis. MOG-IgG testing was not available at that time, and the episode was diagnosed as ADEM based on the overall clinico-radiological presentation, with complete recovery after corticosteroid therapy. Five years later, he presented with fever, acute quadriparesis predominating in the lower limbs, pyramidal signs, and sphincter dysfunction. Brain MRI showed multiple ill-defined subcortical T2-weighted/fluid-attenuated inversion recovery (T2/FLAIR) hyperintense lesions, and spinal MRI demonstrated longitudinally extensive cervical myelitis from the cervicomedullary junction to C6. Cerebrospinal fluid analysis showed marked pleocytosis, elevated protein, absence of oligoclonal bands, and negative infectious studies. Serum MOG-IgG was positive at a titer of 1:100 using a fixed cell-based assay, while AQP4-IgG was negative. He received intravenous methylprednisolone followed by intravenous immunoglobulin because of insufficient initial improvement, with complete clinical recovery at one month and marked radiological regression at six months. This case emphasizes that a confirmed MOG-IgG-positive demyelinating event may occur after a prolonged relapse-free interval following an earlier ADEM-like demyelinating episode, while also underscoring that the first episode should be interpreted cautiously because MOG-IgG testing was unavailable. Long-term follow-up remains essential because short-term clinical and radiological improvement does not establish durable disease control.
2026-06-20 | Suspected Acute Disseminated Encephalomyelitis Presenting With Persistent Vegetative State and Full Neurological Recovery in an Adult: A Case Study
Acute disseminated encephalomyelitis (ADEM) is an autoimmune inflammatory disease of the central nervous system that typically presents with headache, fever, altered consciousness, and seizures. Diagnosis is made clinically and radiologically, supported by the exclusion of mimics. Delayed treatment can lead to severe neurological impairment, including a persistent vegetative state. A 69-year-old Asian female with rheumatic heart disease and prior transverse myelitis presented with hypoxic respiratory failure. On hospital day (HD) 4, she developed a rapid decline in mental status, progressing to a vegetative state with electroclinical seizures. Brain MRI showed diffuse, symmetric T2/fluid-attenuated inversion recovery (FLAIR) hyperintensities involving subcortical white matter, which is an atypical finding for classic ADEM. Extensive infectious and autoimmune testing was unrevealing. Lumbar puncture on HD 11 (prior to steroids) showed no pleocytosis. She remained vegetative for 39 days without response to high-dose corticosteroids. Following a five-day course of intravenous immunoglobulin (IVIG), she showed marked neurological recovery. At discharge, she returned to her baseline functional status. This case illustrates the diagnostic challenges of suspected ADEM in an older adult with atypical symmetric imaging, prolonged vegetative state, and delayed response to immunotherapy. The case adds to the limited literature on extended encephalopathy in suspected ADEM and underscores the role of IVIG when steroid response is unclear.
Access all drug discovery articles and probability of success in trials forecasts:
Access all drug discovery articles and probability of success in trials forecasts:
Drug Discovery Landscape
1 orphan drug designation for Acute disseminated encephalomyelitis.
1 orphan drug designation for Acute disseminated encephalomyelitis.
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
(R)-2-((1-(2-(4-methoxy-3-(2-morpholinoethoxy) phenyl)-5-methylthiazol-4-yl)ethyl)thio)pyrimidine-4,6-diamine | small molecules | FDA | 2021-01-07 | — | Trethera Corporation |
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