Paroxysmal kinesigenic choreoathetosis and abnormal contingent negative variation. A case report

Area of Science:

• Neuroscience
• Movement Disorders
• Clinical Electrophysiology

Background:

• Paroxysmal kinesigenic choreoathetosis (PKC) is a rare movement disorder with unclear etiology and pathophysiology.
• Anticipated movements exacerbate PKC symptoms, suggesting a role for predictive neural processes.

Observation:

• The study examined the contingent negative variation (CNV), a brain potential linked to anticipation, in a PKC patient.
• A significant enhancement of the slow negative wave (SNW), a CNV component, was observed in the patient compared to controls.

Findings:

• Phenytoin sodium therapy effectively reduced PKC attacks.
• Following treatment, the enhanced SNW amplitude in the patient normalized to control levels, indicating a potential biomarker.

Implications:

• This research suggests a neurophysiological link between abnormal CNV/SNW and paroxysmal kinesigenic choreoathetosis.
• The findings may guide future diagnostic approaches and therapeutic strategies for this rare movement disorder.