Parkinson Disease

Question 1

Cardinal Features of PD

Answer 1

Rest tremor
Rigidity
Bradykinesia
Gait impairment

Additional features
Freezing of gait
Postural instability
Speech difficulty
Autonomic disturbances
Sensory alterations
Mood disorders
Sleep dysfunction
Cognitive impairment
Dementia

Question 2

Pathologic hallmark of PD

Answer 2

1. Degeneration of dopaminergic neurons in the substantia nigra pars compacta
2. Reduced striatal dopamine
3. Intracytoplasmic proteinaceous inclusions known as Lewy bodies that primarily contain alpha synuclein

Question 3

Parts of the Basal Ganglia

Answer 3

Striatum (putamen and caudate nucleus)
Subthalamic nucleus
Globus pallidus (interna and externa)
Substantia nigra pars compacta

Question 4

Gene mutation that is most common cause in familial PD

Answer 4

LRRK2 Gene
Commonly seen in Ashkenazi Jew and North African Berber Arabs

Mutations in Parkin Gene should be considered in patients with onset prior to 40 yo

Question 5

Multiple System Atrophy manifests as a combination of :

Answer 5

(1) Parkinsonian
(2) Cerebellar
(3) Autonomic Features

Divided into:

(1) predominant parkinsonian
(2) predominant cerebellar

Question 6

Pathologic characteristics of MSA

Answer 6

Degeneration of SNc, striatum, cerebellum, and inferior olivary nucleus coupled with characteristic glial cytoplasmic inclusions that stain for alpha-synuclein

Question 7

MRI pathology for MSA

Answer 7

Pathologic iron accumulation in the striatum on T2 weighted scans,

high signal change in the region of the external surface of the putamen (putaminal rim) in MSA-p,

or cerebellar and brain stem atrophy (pontine “hot cross buns” sign in MSA-c

Question 8

Form of atypical parkinsonism characterised by

Slow ocular saccades
Eyelid apraxia
Restricted eye movements with particular impairment of downard gaze

Answer 8

Progressive supranuclear palsy

Question 9

MRI pathology in progressive supranuclear palsy

Answer 9

Atrophy of the midbrain with relative preservation of the pons,
“The hummingbird sign” on midsagittal images

Question 10

Characteristic pathology of PSP

Answer 10

Degeneration of the SNc, striatum, subthalamic nucleus, midline thalamic nuclei and pallidum along with neurofibrillary tangles and inclusions that stain for the tau protein

Question 11

Manifests as asymmetric dystonic contractions and clumsiness of one hand coupled with cortical sensory disturbances (apraxia, agnosia, focal limb myoclonus or alien limb phenomenon)

Answer 11

Corticobasal ganglionic degeneration

Question 12

Causes of secondary parkinsonism

Answer 12

Drugs
Stroke
Tumor
Infection
Exposure to toxins e.g. Carbon monoxide and manganese

Question 13

Most common cause of secondary parkinsonism

Answer 13

Dopamine blocking agents such as neuroleptics

Other commonly used drugs include metoclopromide and chlorpromazine

Other drugs:
Tetrabenazine
Calcium channel blockers (flunnarizine, cinnarizine)
Amiodarone
Lithium