Neuromuscular Disorders Flashcards Preview

Neurology Year 3 > Neuromuscular Disorders > Flashcards

Flashcards in Neuromuscular Disorders Deck (39)
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1

What is the neurotransmitter in the NMJ?

Acetylcholine

2

What causes botulism?

Clostridium Botulinum

3

How does a bacterial infection produce the neuromuscular disorder?

The toxins cleave presynaptic protein preventing vesicles fusing with the membrane.
Acetylcholine isn't released in NMJ.

4

How doe botulism present?

Rapid onset weakness with no sensory loss.

5

Lamberton Eaton Syndrome

Anutoantibodies to the Ca2+ so reduced vesicles released as Ca2+ doesn't enter presynaptic bulb.

6

What is the common cause of Lamberton Eaton Syndrome?

Small Cell Carcinoma

7

What is the most common Neuromuscular disorder?

Myasthenia Gravis

8

When does myasthenia present in the population

Women 3rd decade
Men 6-7th decade

9

What causes myasthenia gravis?

Autoimmune antibodies to the acetylcholine receptors on post synaptic plate.
Reduced receptors mean stamina and increased fatigue.

10

At what percentage loss of receptors do symptoms present?

30%

11

What is Myasthenia Gravis associated with?

Thymic Hyperplasia

12

If left untreated how do the muscles in myasthenia gravis react?

Begin to atrophy

13

In what percentage of patients with myasthenia gravis do ACh antibodies occur?

80-90%

14

What are the clinical signs of Myasthenia Gravis?

Fluctuating weakness
Extraoccular weakness - drooping eyes double vision
Struggle to speak and chew
Proximal limb weakness

15

What is the acute treatment for Myasthenia Gravis?

Acetylcholinesterase inhibitors - Pyridostigmine
IV Immunoglobulin
Plasma Exchange
Thymectomy

16

What is the acute treatment for chronic Myasthenia Gravis?

Steroid
Steroid sparing agents

17

What is the course of steroid used in chronic Myasthenia Gravis?

High does 40-60mg prednisolone for a month

18

What steroid sparing agents are used in chronic Myasthenia Gravis?

Azathioprine
Mycophenolate

19

What drugs should be avoided in a Myasthenia Gravis?

Gentamicin

20

What is the mortality in Myasthenia Gravis?

3/4%

21

What are the commonest causes of death in Myasthenia Gravis?

Respiratory failure
Aspiration pneumonia
Side effects of immunosuppression

22

What are the signs of muscular disease?

Myalgia
Muscle weakness
Wasting
Hypoflexia

23

What are fasciculations?

Visible fast fine spontaneous twitches

24

What are some non pathological causes of fasciculations?

Stress fatigue caffeine

25

What is a pathological cause of fasciculations?

Denervated muscles that are hyper excitable

26

What grading system is used to determine the power in someone's limbs?

MRC - Muscle Power Grading
0 - 5
0 = no movement
5 = normal strength ( subjective to the patient)

27

What investigations are undertaken in a suspected NMJ disease?

Blood test - Creatine Kinase
Muscle Biopsy
MRI - Muscle tissue

28

Describe the appearance of polymyositis?

Symmetrical rapidly progressing proximal muscle weakness

29

What investigations are undertaken in polymyositis?

Raised Creatine Kinase
Very reactive to steroid <24 hours

30

What's dermatomyositis?

Clinically similar to polymyositis but + Heliotrope rash