Huntington Disease — SCE Neurology MCQ

Instant feedback + full explanation. One question, done properly.

EasyNeurodegenerative DiseaseHuntington DiseaseSCE Neurology

A 45-year-old man presents with progressive chorea, psychiatric disturbance (irritability, depression), and cognitive decline over 2 years. His father died of a similar condition aged 50. Genetic testing reveals 44 CAG repeats in the HTT gene. What is the diagnosis?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: C — Huntington disease

Huntington disease is an autosomal dominant trinucleotide repeat (CAG) disorder in the HTT gene. ≥36 CAG repeats are pathogenic (≥40 is fully penetrant). The classic triad is chorea, psychiatric disturbance, and progressive cognitive decline. Caudate atrophy on MRI is characteristic. A: Wilson disease presents before age 40 with hepatic and neurological features. C: Sydenham chorea follows streptococcal infection in children. D: Benign hereditary chorea is non-progressive. E: Neuroacanthocytosis has acanthocytes on blood film.

Reference: EAN Huntington Disease Guidelines; Genetic Testing Standards