Brain atrophy patterns in anti-IgLON5 disease.

Area of Science:

• Neuroimmunology
• Neurodegeneration
• Clinical Neurology

Background:

• Anti-immunoglobulin-like domain containing 1 (IgLON5) disease is a rare autoimmune encephalitis with varied symptoms like sleep disturbances and movement disorders.
• It's associated with specific antibodies, HLA types, and brainstem tauopathy, but in vivo progression data is limited.
• Understanding disease progression and atrophy patterns is crucial for patient management.

Purpose of the Study:

• To investigate the relationship between clinical manifestations and brain atrophy patterns in Anti-IgLON5 disease.
• To analyze in vivo patient data for disease progression and identify specific atrophy sites.
• To establish normative data for atrophy measurements in clinical assessments.

Main Methods:

• Multi-center study involving 127 patients with Anti-IgLON5 disease across twelve countries.
• Collection and analysis of clinical data and brain Magnetic Resonance Imaging (MRI) scans.
• Age-independent analysis to assess atrophy patterns and ventricular enlargement, correlating with clinical symptoms.

Main Results:

• Patients often develop complex, multi-system phenotypes, with neuromuscular issues rarely appearing late in the disease.
• Severe, structure-specific atrophy observed in the hypothalamus, brainstem, accumbens, and basal ganglia compared to controls.
• Brainstem atrophy progression was noted, and atrophy patterns correlated with symptoms (e.g., basal ganglia and movement disorders).

Conclusions:

• Distinct brain atrophy patterns in Anti-IgLON5 disease reflect underlying pathophysiology, including autoantibody binding and tau deposition.
• The brainstem is identified as the central hub for the disease's pathology.
• Findings support incorporating atrophy measurements into routine assessments for monitoring disease trajectory and evaluating treatments.