An Autopsy-proven Case-based Review of Autoimmune Encephalitis.

Area of Science:

• Neurology
• Immunology
• Pathology

Background:

• Autoimmune encephalitis (AIE) is the most common noninfectious encephalitis.
• Definitive diagnosis of AIE is challenging due to the rarity of biopsy or autopsy.
• CD8+ T-lymphocyte predominant encephalitis is a rare presentation of AIE.

Purpose of the Study:

• To present pathological findings of AIE in a unique case.
• To review literature on CD8+ T-lymphocyte predominant encephalitis.
• To emphasize the role of pathological examination in AIE diagnosis.

Main Methods:

• Case report of an 80-year-old male patient with AIE.
• Detailed description of clinical progression, imaging, laboratory data, and autopsy findings.
• Literature review on AIE and CD8+ T-lymphocyte encephalitis.

Main Results:

• Autopsy revealed CD8+ T-lymphocyte predominant lymphocytic infiltration in brain tissue.
• No evidence of viral infection or neoplasm was found.
• The patient also had Alzheimer's disease and other age-related pathologies.

Conclusions:

• Pathological examination is crucial for diagnosing AIE, particularly when autoantibody testing is unavailable or multiple diseases are suspected.
• CD8+ T-lymphocyte infiltration suggests an autoimmune process in encephalitis.
• This case underscores the complexity of diagnosing AIE in elderly patients with comorbidities.