To describe a case of a 62-year-old female former alcoholic with epilepsy, worsening aphasia, and progressive left hemispheric atrophy.

Rasmussen’s encephalitis is a rare clinical entity which includes focal seizures, unihemispheric inflammation, and progressive cortical atrophy. Only 10% of diagnoses are late onset, but not extending beyond early adulthood. Rasmussen-like presentations are poorly understood in older adults. Subacute encephalopathy and seizures in alcoholism (SESA) can be unilateral; however, existing literature lacks longitudinal outcomes. A recent case series described a group of older autoimmune encephalitis patients with Rasmussen encephalitis-like progressive unilateral cortical atrophy. One third had a history of alcohol abuse. Importantly, they improved with immunotherapy.

Unilateral cortical inflammation preceding progressive atrophy is rare. While Rasmussen’s encephalitis is seen in childhood, such a presentation in the older adult population remains a diagnostic challenge. In alcoholic patients, SESA is on the differential. A recent case series reported Rasmussen-like changes in older individuals with autoimmune encephalitis, including patients with a history of alcohol use disorder. Our case can help to expand the literature on late onset unilateral cortical encephalitis, with the subsequent development of progressive atrophy, aphasia, and epilepsy.