Clinical Manifestations.

Area of Science:

• Neurology
• Immunology
• Neuroimaging

Background:

• Central nervous system autoantibodies are increasingly recognized in mild cognitive impairment (MCI) and dementia.
• Previous research has not comprehensively detailed the clinical and neuroimaging profiles of MCI associated with autoantibodies.

Purpose of the Study:

• To characterize the clinical and neuroimaging features of MCI patients with central nervous system autoantibodies.
• To investigate potential biomarkers for identifying MCI with autoantibodies.

Main Methods:

• Retrospective analysis of 97 MCI patients tested for autoantibodies using cell-based assays (CBA).
• Comparison of clinical characteristics, magnetic resonance imaging (MRI) for atrophy, 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET) for glucose metabolism, and Pittsburgh Compound B positron emission tomography (PIB-PET) for amyloid deposition between antibody-positive and negative groups.

Main Results:

• 10.3% of MCI patients were autoantibody-positive, primarily with intracellular antibodies.
• Antibody-positive MCI patients showed higher whole-brain glucose metabolism on FDG-PET, particularly in the frontal lobe, and a positive correlation between glucose metabolism and autoantibody presence.
• No significant differences in cortical atrophy (MRI) or amyloid deposition (PIB-PET) were observed between groups. Abnormal tumor markers were more frequent in the antibody-positive group.

Conclusions:

• Abnormal tumor markers and increased frontal lobe glucose metabolism on FDG-PET may indicate MCI with autoantibodies.
• The findings suggest a pathogenic pathway for MCI with autoantibodies that is independent of amyloid deposition.
• Further research is warranted to explore the specific mechanisms and clinical implications of autoantibody-associated MCI.