Childhood-onset Huntignton´s disease. A rare presentation

Area of Science:

• Neurology
• Genetics
• Pediatrics

Background:

• Huntington's disease (HD) is a rare autosomal dominant neurodegenerative disorder.
• It results from CAG triplet expansions in the huntingtin gene, leading to anticipation (earlier onset in successive generations).
• Childhood-onset HD (before age 10) exhibits distinct clinical features compared to the adult form.

Observation:

• A 5-year-old girl with a family history of HD presented with progressive language impairment and motor deficits.
• Clinical manifestations included walking instability, rigidity, dystonia, and choreic movements.
• Brain MRI revealed basal ganglia atrophy; genetic testing confirmed 51 CAG repeat copies.

Findings:

• Childhood-onset HD is characterized by motor impairment, behavioral issues, and developmental delays, with chorea being less common.
• Progressive motor and cognitive decline are key indicators for considering childhood-onset HD.
• Anticipation necessitates careful family history evaluation, even in the absence of known affected relatives.

Implications:

• This case highlights the distinct clinical presentation of childhood-onset Huntington's disease.
• Early diagnosis is vital for appropriate management and genetic counseling.
• Understanding the anticipation phenomenon is crucial for families with a history of HD.