CVA, Parkinson’s and MG

Question 1

bulbar

Answer 1

involvement of speech

Question 2

opthalmoplegia

Answer 2

eyes not moving together
muscle problem

Question 3

bilateral asymmetrical fatiguable ptosis

Answer 3

ptosis- drooping of upper eyelid

Question 4

myasthenia gravis

Answer 4

autoimmune, antibody mediated disorder of the neuromuscular junction

classically starts w ocular symptoms then progresses over the years to proximal weakness

worsens with exertion

can lead to life threatening respiratory decompensation

Question 5

symptoms of MG and presentation

Answer 5

fluctuating fatigability and weakness affecting ocular, bulbar, and proximal limb skeletal muscle groups

Cogan’s lid twitch and ice pack test positive
ptosis
opthalmoplegia

Question 6

pathophysiology of MG

Answer 6

acetylcholine receptor gets blocked/destroyed by antibody
acetylcholine cannot bind

acetylcholinesterase breaks down Ach for inhibition of signal (so can inhibit these to reduce symptoms)

fewer receptors=fewer nerve signals
muscle weakness

Question 7

investigations for MG

Answer 7

antibodies in blood eg. Anti-AchR (acetylcholinesterase), anti-MUSK,

electrophysiology - repetitive nerve stimulation

edrophonium test- a reversible acetylcholinesterase inhibitor

check for other autoimmune conditions

CT chest- AchR Ab +ve

Question 8

thymoma and MG

Answer 8

presence of thymoma causes MG

thymus produces AntiAchR antibodies

thymoma
when thymus gland is overgrown/
tumour grown

can remove surgically

Question 9

triggers for MG

Answer 9

physical exertion
infections
surgery
pregnancy
hypokalaemia

drugs: Abx (antibiotics)
CCBs
beta blockers
diazepam

Question 10

treatment for MG

Answer 10

AchR inhibitor first (acetylcholinesterase inhibs)

then
presnisolone
steroid sparing agents
acute deterioration (IVIG or plasma exchange)
monoclonal antibody treatments

thymectomy for thymoma

Question 11

Parkinson’s

Answer 11

Parkinson’s disease (PD) is a degenerative, progressive disorder that affects nerve cells in deep parts of the brain called the basal ganglia and the substantia nigra

sporadic
onset in late middle age

Question 12

Parkinson’s presenting symptoms

Answer 12

Facial hypomimia.
Right sided rest tremor, bradykinesia and rigidity.
Flexed posture, shuffling gait and decreased arm swing on the right.
Common in elderly, but can present in young

• Presenting symptoms
  – Tremor
  – difficulty with fine movements
  – stiffness of a limb (e.g. Frozen shoulder)
  – falls

Question 13

Parkinsons pathology main features

Answer 13

Loss of pigmented (dopamine-containing) neurons in substantia nigra

Alpha Synuclein (microtubule protein) misfolding is the main intracellular trigger of cell death - becomes sticky and clumps together to form lewy bodies

Presence of Lewy bodies - [pink] intracytoplasmic inclusions in the neurons that contain brown neuromelanin - toxic to cells and kills dopaminergic neurons

Question 14

PD pathophysiology
dopamine role

Answer 14

Neurotransmitters carry messages between neurons by crossing the synapse between them
* To fine-tune coordination of movement, the amount of dopamine in the synapse is regulated. Too much or too little dopamine makes smooth continuous movement difficult

Question 15

PD cardinal features
Akinesia/Bradykinesia

Answer 15

• Slowness of movement
  + decrement in amplitude of repetitive movement
• Difficulty initiating movement
• Mask-like facies (facial hypomimia)
• Reduced spontaneous blinking
• Lack of arm swing
• Finger taps, playing piano, heel taps

repetitive test
movement gets smaller and slower

Question 16

PD cardinal features
Tremor

Answer 16

• 4-7 Hz
• Rest
• Pill-rolling
• Reduces on action
• Unilateral initially
• Arms, legs, head
• Hands in lap, outstretched, in front of face, finger-to-nose

Question 17

PD cardinal features
Rigidity

Answer 17

• Stiffness through a range of movement
• Like a lead pipe combined with tremor ‘cogwheel’ rigidity
• Examine at wrist, elbow and other joints, co-activation

Question 18

PD cardinal features
Postural instability

Answer 18

Gait – stooped, festinant (shuffling steps)
* Falls
* Ability to stand with arms crossed, gait, pull test
Positive pull test (>2 corrective steps back or patient is about to fall)

Question 19

PD non motor features

Answer 19

Neuropsychiatric
– Depression, apathy
– Anxiety

Cognitive
– Dementia (fluctuating alertness and cognition,visual hallucinations)

Sleep-related problems
– Excessive daytime sleepiness
– Vivid dreams
– REM sleep behaviour disorder

Autonomic dysfunction
– Postural hypotension
– Urinary incontinence
– Constipation
– Erectile dysfunction

Question 20

PD diagnosis

Answer 20

• History & examination usually confirm diagnosis
  Queen square Brain bank diagnostic criteria
• DAT scan (helps differentiate between essential tremor or Parkinson’s Disease) measures dopaminergic activity

Question 21

secondary parkinsonism

Answer 21

when symptoms similar to Parkinson disease are caused by certain medicines, a different nervous system disorder, or another illness

can be caused by
Brain injury.
Diffuse Lewy body disease (a type of dementia)
Encephalitis.
HIV/AIDS.
Meningitis.
Multiple system atrophy.
Progressive supranuclear palsy.
Stroke.

Question 22

treatment of pd

Answer 22

Levodopa/L-Dopa
* Increases circulating dopamine in the brain, therefore improving the symptoms of PD
* Effects eventually wear off with time
* Side effects - nausea & vomiting, confusion & hallucinations, end-of -dose dyskinesias, on-off syndrome

Dopamine agonists
* Less effective than L-dopa, but fewer late unwanted dyskinesia
* Side effects – impulse control disorders (e.g. compulsive gambling, shopping, hypersexuality, punding)

MAOB inhibitors
* Inhibits breakdown of dopamine

COMT inhibitors
* Inhibits breakdown of dopamine

Apomorphine
– Directly acting dopamine agonist
– Given sub-cutaneously as daily
infusion or bolus injections
– Best method of smoothing out
fluctuations/managing
troublesome
dyskinesias in advanced PD
– Side effects - nausea, confusion, low BP

Duodopa
– L-dopa administered continuously
and directly into small intestine via
PEJ tube for rapid uptake into
bloodstream