Flashcards in OHCM - Parkinsonism Deck (23):
Parkinson's clinical triad:
2. Rigidity/incr. tone.
4. Shuffling gait.
1. Worse at rest; often "pill-rolling" of thumb over fingers.
2. 4-6 cycles/sec (SLOWER than cerebellar tremor).
3. Distinguish from "essential tremor", which is symptomatic postural and action tremor of the upper limbs and head.
Rigidity + tremor = "cogwheel rigidity" felt by the examiner during rapid pronation/supination.
Slow to initiate movement and slow, low-amplitude excursions in repetitive actions, eg decr. blink rate, monotonous hypophonic speech, micrographia.
1. Decr. arm swing.
2. Festinance (shuffling steps with flexed trunk, as if chasing one's centre of gravity).
3. Freezing at obstacles or doors.
4. Expressionless face (hypomimesis).
Parkinsonism - Etiology:
1. Idiopathic PD.
2. Drugs (neuroleptics, metoclopramide, prochlorperazine).
3. Rarely: trauma/boxing, encephalopathy post-flu, manganese or copper toxicity (Wilson), HIV, Parkinson's-plus syndromes.
1. Mutations in FbXo7 may be important in disrupting mitophagy, the process CNS cells use to eliminate faulty mitochondria.
2. PINK1 and Parkin also play a role.
Idiopathic PD - Presentation:
Bradykinesia/hypokinesia + one or more of:
1. Tremor at rest (one side worse).
2. Postural instability +/- rigidity.
Idiopathic PD - Other signs may be subtle:
1. Poor decoding of the emotional content of speech (prosody).
2. Poor executive functioning.
3. REM sleep disorders.
Idiopathic PD - Non-motor features:
1. Sense of smell reduced.
3. Visual hallucinations.
5. Dribbling of saliva.
6. Depression and dementia.
Idiopathic PD - A devastating symptom:
Poor simultaneous motor and cognitive functions can lead to freezing while walking.
Idiopathic PD - Typical age at onset:
Idiopathic PD - Prevalence:
0.6% - 60-64.
3.5% - 85-89.
Mitochondrial DNA dysfunction causes degeneration of dopaminergic neurons in the substantia nigra pars compacta (associated with Lewy bodies), hence decr. striatal dopamine levels.
Rx - Neuropsychiatric complications:
1. Depression, dementia, psychosis --> May reflect progression or SE.
2. Try SSRIs for depression.
3. Distinguish drug-induced psychosis (consider reducing DA-agonist doses) from disease progression (try atypical antipsychotics, eg quetiapine, olanzapine).
Levodopa is used combined with ...?
A dopa-decarboxylase inhibitor, such as Madopar (co-beneldopa) or Sinemet (co-careldopa).
5 Parkinson's-plus syndromes:
1. Progressive supranuclear palsy (PSP - Steele-Richardson-Olszewski syndrome).
2. Multiple system atrophy (MSA - Shy-Drager).
3. Lewy body dementia.
4. Cortico-basal degeneration.
5. Vascular Parkinsonism.
Progressive supranuclear palsy (PSP - Steele-Richardson-Olszewski syndrome):
1. Early postural instability + VERTICAL gaze palsy +/- Falls.
2. Rigidity of trunk > in limbs.
3. Symmetrical onset.
4. Speech + Shallowing problems.
5. Little tremor.
Multiple system atrophy (MSA - Shy-Drager):
1. Early autonomic features --> Impotence/incontinence, postural hypotension.
2. Cerebellar + pyramidal signs.
3. Rigidity > tremor.
Lewy body dementia:
Fluctuating cognition with VISUAL hallucinations + EARLY dementia.
Cortico-basal degeneration (CBD):
1. Akinetic rigidity involving one limb.
2. Cortical sensory loss (eg astereognosis).
3. Apraxia (even autonomous interfering activity by affected limb - the ALIEN LIMB phenomenon).
2-5% of PD:
1. Pyramidal signs (legs).
2. Diabetic/hypertensive patient who falls or has gait problems, (eg ataxia (no festination).