huntington's

Question 1

definition

Answer 1

Huntington’s disease is a slowly progressive, neurodegenerative disorder characterised by chorea, incoordination, cognitive decline, personality changes, and psychiatric symptoms, culminating in immobility, mutism, and inanition. It is an autosomal dominant, trinucleotide repeat disorder that affects men and women equally. It characteristically appears in mid-adult life but can occur at any age. Treatment for depression, and to some degree behavioural problems and chorea, is possible. There are no disease-modifying therapies.

patients have chorea as a significant initial presenting feature

mostly affects the striatum

Question 2

symptoms

Answer 2

• personality changes
• irritability and impulsivity
• twitching or restlessness
• chorea
• loss of coordination, fine motor coordination
• slow raid (saccadic) eye movements
• motor impersistence (cannot sustain movements e.g. squeezing eyes shut or sticking out tongue)
• imparted tandem walking (could be because of coordination, chorea etc.)
• loss of cognitive ability or executive function
• obsessive, compulsive behaviour

Question 3

risk factors

Answer 3

• expansion of CAG repeat length at N-terminal end of the huntington gene
• family history

Question 4

investigations

Answer 4

1st:
clinical diagnosis

others:

• CAG repeat testing
• MRI/CT