Characteristics and predictors of disease course in children initially presenting with ADEM

Area of Science:

• Pediatric Neurology
• Neuroimmunology
• Demyelinating Diseases

Background:

• Acute disseminated encephalomyelitis (ADEM) presents with acute polyfocal neurological symptoms, encephalopathy, and multifocal demyelination, often in childhood.
• Initial diagnosis of ADEM is challenging, with up to 20% of children with multiple sclerosis (MS) or neuromyelitis optica spectrum disorder (NMOSD) initially misdiagnosed with ADEM.

Purpose of the Study:

• To describe characteristics of children with monophasic ADEM versus recurrent demyelinating syndromes.
• To identify clinical and imaging features predictive of a monophasic course in pediatric ADEM.

Main Methods:

• Multicenter observational study involving 837 children diagnosed with ADEM, MS, or NMOSD across 12 pediatric MS centers.
• Descriptive statistics and logistic regression analysis were used to analyze patient characteristics, clinical/imaging features, and outcomes.
• Follow-up data, averaging 5.7 years, were used to assess diagnostic stability and reclassification rates.

Main Results:

• ADEM patients were younger (mean age 5.2 years) and predominantly male (66%) compared to MS/NMOSD groups.
• After 2 years, 83% of initially diagnosed ADEM cases retained their diagnosis.
• Older age at onset, optic neuritis, and gadolinium-enhancing lesions were associated with reclassification from ADEM to MS, NMOSD, or other demyelinating disorders (DDNOS).

Conclusions:

• Children with monophasic ADEM are typically younger at onset and less likely to present with optic neuritis or gadolinium-enhancing lesions.
• These features can help differentiate monophasic ADEM from other demyelinating disorders in children, improving diagnostic accuracy.
• Accurate initial diagnosis is crucial for appropriate management and prognosis in pediatric demyelinating diseases.