Objective: To describe a case of childhood-onset progressive multiple sclerosis with dementia and evidence of extensive cortical demyelination from brain biopsy specimen.
Design: Case report.
Setting: Mayo Clinic, Rochester, Minnesota.
Patient: A 26-year-old man with a history of behavioral changes starting at the age of 13 years followed by progressive dementia.
Interventions: Neurological examination, magnetic resonance imaging, cerebrospinal fluid studies, neuropsychological testing, and brain biopsy.
Results: Magnetic resonance imaging scans showed numerous T2-weighted hyperintensities throughout the central nervous system not associated with contrast enhancement. Brain biopsy specimens showed cortical and subcortical demyelination. All 3 types of cortical demyelinating lesions were observed: leukocortical, intracortical, and subpial. Lesions were associated with profound microglial activation. The patient continued to progress despite attempts to treat with multiple sclerosis disease-modifying therapies.
Conclusions: Multiple sclerosis should be considered in the diagnosis of progressive dementia in children and young adults. Cortical demyelination may contribute to cognitive decline in patients with dementia due to multiple sclerosis.