Acute Hemorrhagic Leukoencephalitis with Concurrent Retinal Vasculitis in an Elderly Japanese Patient: A Case Report

A 68-year-old Japanese man developed a fever, headache, hiccups, and altered consciousness. Brain magnetic resonance imaging (MRI) revealed a hemorrhagic lesion in the right temporal lobe and multiple high-intensity white matter lesions. A brain biopsy showed pathological findings consistent with acute disseminated encephalomyelitis (ADEM), suggesting a diagnosis of acute hemorrhagic leukoencephalitis (AHLE), an aggressive ADEM variant. The patient also developed myodesopsia and was diagnosed with retinal vasculitis, likely due to a hyperimmune state caused by AHLE. Corticosteroids enabled full recovery. Although AHLE is uncommon in elderly individuals, clinicians should be aware of its occurrence in this patient subgroup and recognize potential retinal manifestations associated with AHLE.