A 38-year-old man presents with involuntary facial grimacing, shrugging of the shoulders, and jerking movements of the limb. His father was similarly affected. There is also a history of mood changes for the past 3 months. On examination, he appears restless with intermittent slow movements of his hands and face. He has difficulty performing rapid finger movements, and tone is decreased in the upper and lower limbs. Which of the following is most likely to represent the progression of his illness?
(A) a normal life span
(B) a 50% chance of only male children
being similarly affected
© mental deterioration
(D) eventual development of rigidity
(E) development of hemiparesis
solution:
© This is a case of Huntington’s chorea. It is an autosomal dominant gene (found on the short arm of
hromosome 4), and male and female children are equally affected. Movement disorder, mental deterioration, and personality change are the hallmarks of the disease, but can be very subtle initially. The disease starts
typically between ages 35 and 40 (although the variation is wide) and runs its course in about 15 years. The akinetic rigid variety (Westphalvariant) of Huntington’s typically has a childhood onset