Huntington's disease

George Huntington (1850-1916)

American physician who contributed a classic clinical description of the disease that bears his name—Huntington's Disease (HD), a hereditary neurodegenerative disease. Huntington described this condition in the first of only two scientific papers he ever wrote

HD, aka Huntington Chorea affects men and women (differently OR equally). 4 to 10 cases in 100,000 people (frequency between 0.004% and 0.01%)

equally

Chorea is defined as (brief OR prolonged), irregular, unpredictable, purposeless movements that flow from one body part to another without a rhythmic pattern

brief

HD is a (hyper- OR hypo-kinetic) disorder

hyperkinetic

HD symptoms are characterized:

• excessive motor activity

• involuntary movements (dyskinesias)

• (decreased OR increased) muscle tone

decreased

Behavioral/emotional alteration and cognitive (decline OR incline) may precede motor abnormalities. This emphasizes the Importance of cognitive and neuropsychological tests to identify the pre-symptomatic carriers of the disease.

decline

HD is a dominant autosomal inherited disease characterized by the (reduction OR expansion) of a triplet repeat CAG, that encodes for Glutamine, in the (N-terminal OR C-terminal) domain of the protein

expansion; N-terminal

HD is caused by selective degeneration of the GABAergic neurons in the striatum, particularly in the (caudate OR putamen)

caudate

Average age of motor symptom onset is between 30 and 50 (years OR months) old, which correlates with one’s CAG repeat length

years

What are the 3 stages of HD?

1. pre-symptomatic

   1. confirmed expanded HD gene through genetic testing, but NO HD SYMPTOMS at this point

2. prodromal

   1. characterized by subtle motor, cognitive and behavioral changes like depression, inability to identify emotion, and impulsiveness. This can be YEARS before a clinical diagnosis when motor symptoms are obvious

3. manifest

   1. today, a clinical diagnosis requires obvious motor symptoms, like chorea. Manifest HD advances through stages with increasing motor and cognitive symptoms leading to functional decline

List the specific localization of Basal Ganglia in a coronal section

• striatum

  • caudate nucleus

  • putamen

• globus pallidus

• substantia nigra

• subthalamic nucleus