Clinical Case: Huntington's and Parkinson's

Question 1

describe where a lesion would be in Huntington’s

Answer 1

Question 2

describe the genetics of Huntington’s

Answer 2

• autosomal dominant inheritance (chromosome 4q)
• >40 CAG trinucleotide repeats
• paternal anticipation

Question 3

describe symptoms seen in Hungtington’s

Answer 3

• mental disorder occurs prior to cognitive dysfunction
  
  • depression occurs >50%
• diminished work performance
• abnormality of movement occurs first in hands and face
• increased blinking and tongue protrusion
• NO motor weakness

Question 4

describe treatment for Huntington’s

Answer 4

• neuroleptics (block dopamine)
• tetrabenazine (depletes dopamine)

Question 5

Huntington’s chorea is caused by a reduced number of ____ neurons in the ____

Answer 5

Huntington’s chorea is caused by a reduced number of D2 neurons in the striatum (caudate nucleus + putamen)

Question 6

describe where the lesion in Parkinson’s disease is

Answer 6

Question 7

describe symptoms seen in Parkinson’s

Answer 7

• mask-like facies, hypophonic voice, micrographia
• cog-wheel rigidity, 4-5 Hz resting tremor
• unable to rise from chair without assistance
• slow, shuffling gait with reduced arm swing
• akinesia - difficulty initiating movement
• postural instability

Question 8

cell in which structure are dying in Parkinson’s?

Answer 8

substantia nigra pars compacta

Question 9

describe treatment for Parkinson’s

Answer 9

• drugs:
  
  • dopamine agonists
  • L-dopa
  • COMT inhibitors
  • MAO-B inhibitors
• surgery
  
  • deep brain stimulation (STN, GPi)
  • pallidotomy of GPi