“…SSPE presents predominantly in the childhood and early adolescent groups, with rare cases of onset at 25, 49, 52, and 61 years old. 5–7 SSPE with an onset in a sexagenarian is rare, but it has been considered underdiagnosed and underreported as a cause of dementia. The differential diagnosis of subacute dementia and/or myoclonus in adults can be summarized into genetic, neoplastic, paraneoplastic, inflammatory-autoimmune, neurodegenerative, neuroinfection, CNS trauma, CNS vasculopathies, toxicity, organ failure, nutritional endocrine, and acquired metabolic-related causes.…”