Paroxysmal kinesigenic choreoathetosis associated with prenatal brain damage

Area of Science:

• Neurology
• Neuroscience
• Pediatric Neurology

Background:

• Paroxysmal kinesigenic choreoathetosis (PKC) is a rare movement disorder characterized by sudden, brief episodes of involuntary movements.
• Understanding the neurobiological underpinnings of PKC, particularly in pediatric cases with significant brain abnormalities, remains an area of active research.

Observation:

• A 15-year-old patient presented with paroxysmal kinesigenic choreoathetosis, accompanied by right-sided hemiparesis, homonymous hemianopsia, and impaired smooth pursuit.
• Attacks were triggered by activity, typically lasting under five minutes, and were not associated with epileptic activity on EEG.
• Neuroimaging revealed extensive structural abnormalities, including a porencephalic cyst and atrophy in the left hemisphere, alongside T2-weighted signal changes near the left putamen.

Findings:

• Cerebral blood flow studies indicated hypoperfusion in the basal ganglia and affected brain regions, correlating with structural lesions.
• A significant discrepancy was noted between the extent of brain lesions and the relatively mild neurological deficits observed.
• Neuronal plasticity in an immature brain is proposed as the primary mechanism explaining the limited symptomatology despite severe brain damage.

Implications:

• The findings suggest that early-onset brain lesions may result in delayed manifestation of movement disorders like PKC due to compensatory mechanisms.
• This case highlights the critical role of neurodevelopmental plasticity in modulating the clinical expression of neurological conditions.
• Further research into brain plasticity could offer novel therapeutic targets for movement disorders originating from early brain injury.