More than memory impairment in voltage-gated potassium channel complex encephalopathy

Area of Science:

• Neuroscience
• Immunology
• Cognitive Science

Background:

• Autoimmune encephalopathies (AEs) are neurological disorders impacting cognition.
• Memory impairment is common in AEs, but comprehensive cognitive domain assessment is lacking.
• Voltage-gated potassium channel complex antibodies (VGKCC-Abs) are associated with specific AE phenotypes.

Purpose of the Study:

• To conduct an unbiased cognitive evaluation in patients with VGKCC-Ab AE.
• To identify specific cognitive strengths and weaknesses in this patient group.
• To delineate the detailed cognitive profile of VGKCC-Ab AE.

Main Methods:

• Comprehensive neuropsychological testing of 12 VGKCC-Ab AE subjects across memory, executive functions, visuospatial skills, and language.
• Clinical magnetic resonance imaging (MRI) in 10 subjects.
• Serial cognitive testing in 5 subjects to analyze changes over time.

Main Results:

• Mild to moderate impairments observed in memory (mean Z = -1.9) and executive functions (mean Z = -1.5).
• Variable language impairments were noted, while visuospatial skills were generally preserved.
• MRI revealed T2 hyperintensities in the medial temporal lobe and basal ganglia.
• Serial testing showed heterogeneous cognitive recovery, with some patients exhibiting residual deficits.

Conclusions:

• VGKCC-Ab AE is characterized by deficits in memory, executive functions, and language, with preserved visuospatial abilities.
• Domain-specific cognitive testing is crucial for understanding the complex cognitive phenotypes in VGKCC-Ab AE.
• Findings expand previous neuropsychological analyses of VGKCC-Ab AE.