LAUSR

A man in his 60s presented with a worsening headache, confusion and expressive dysphasia which, on admission, progressed to a falling Glasgow Coma Score and seizures. He was subsequently admitted to the intensive care unit. The clinical diagnosis was antibody-negative autoimmune encephalitis. Despite immunotherapy, the patient died 5 months after initial presentation and postmortem examination revealed he had CD8 encephalitis. This case demonstrates that CD8 encephalitis can present similarly to autoimmune encephalitis both clinically and on imaging. A brain biopsy would have revealed the diagnosis in life, although this would not have altered his treatment.