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Flashcards in Motor neuron disease Deck (82)
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1
Q

What is another name for MND?

A

Amyotrophic Lateral Sclerosis (ALS)

2
Q

What is motor neuron disease?

A

Degeneration of upper and lower motor neurons

3
Q

What is the cause of MND?

A

Unknown

4
Q

How does MND progress?

A

It is progressive and usually fatal within 4 years of onset

5
Q

What is the incidence of MND?

A

1.5/100,000

6
Q

What is the prevalence of NMD?

A

6/100,000

7
Q

How does NMD differ from peripheral neuropathies?

A

It is solely motor and not sensory

It involves upper and lower motor neurons

8
Q

What is the prognosis from onset of MND?

A

50% die within 3-4 years
20% live > 5 years
10% live > 10 years
Occasionally patients live 20 years

9
Q

What are risk factors for ALS?

A

Older age
Family history
Male gender

Unclear:

Occupational/environmental factors: job, military exposure, metals, pesticides, viruses

Lifestyle: smoking, low BMI, diet, physical exercise, trauma

10
Q

Why might exercise be causing MND?

A

May be due to over-excitation of the nerves

11
Q

Why might male gender be a risk factor?

A

May be due to hormones

More common in post-menopausal women

12
Q

What is the average age of onset of MND?

A

~65 (wide range)

13
Q

Which race is more likely to get MND?

A

White

14
Q

What is known about the pathophysiology of MND?

A

ALS kills motor nerve cell, causing muscles to weaken

15
Q

What does the amyotrophic in ALS refer to?

A

The muscles becoming thinner due to decreased lower motor neuron involvement

16
Q

What does lateral sclerosis refer to?

A

The whiteness in the cortical spinal tract

17
Q

What are the main sites affected by ALS?

A

Tongue (bulbar muscles)

Arms

Legs

18
Q

What causes ALS death?

A

Respiratory muscle functions failing

19
Q

What are the types of MND?

A

ALS

Progressive muscular atrophy – lower motor neuron

Progressive bulbar palsy – tongue and speech

Primary lateral sclerosis – upper motor neuron

20
Q

What % of MND patients have a family history?

A

5-10% have family history

21
Q

TRUE or FALSE?

Very few genes have been identified to be associated with MND

A

FALSE

Many have been identified (both in familial and apparently sporadic)

22
Q

What are the symptoms of motor neuron disease?

A

Fasiculations
Wasting and weakness of muscles
Brisk reflexes
May have cognitive involvement

23
Q

What causes fasiculations and muscle wasting?

A

Lower motor neurone degeneration

24
Q

What causes brisk reflexes?

A

Upper motor neurone degeneration

25
Q

What is the cognitive involvement similar to?

A

Frontal dementia

26
Q

What are beginning signs of ALS?

A

Tripping, trouble buttoning, slowed speech and trouble swallowing

27
Q

Which MND has the best survival?

A

Primary lateral sclerosis

28
Q

What are the bulbar upper motor neuron signs?

A

Jaw jerk positive
Palatal spasticity
Tongue spasticity

29
Q

What are the bulbar lower motor neuron signs?

A

Facial fasiculations
Tongue wasting
Palatal weakness and fasiculations

30
Q

What are the cervical upper motor neuron signs?

A

Increased tone
Hyper-reflexia
Preserved reflexes in wasted muscles

31
Q

What are cervical lower motor neuron signs?

A

Fasiculations and weakness
Muscle Wasting
Absent reflexes

32
Q

What are lumbar upper motor neuron signs?

A

Increased tone and or extensor plantars
Hyper-reflexia
Preserved reflexes in wasted muscles

33
Q

What are lumbar lower motor neurone signs?

A

Fasiculations and weakness
Muscle wasting
Absent reflexes

34
Q

How do you diagnose MND?

A

Clinical history
Physical examination
EMG as support

Observe:
Progression of symptoms and signs
Normal Sensation

35
Q

What should you find on physical examination of MND?

A

Lower motor neuron signs: weakness, wasting, fasiculations

Upper motor neuron signs: spasticity, brisk reflexes

36
Q

Why do we do EMG?

A

To support findings of active denervation

37
Q

TRUE or FALSE?

Upper and lower motor neurone features should be present in more than one region for MND

A

TRUE

38
Q

What are the criteria used to diagnose ALS and when is it used?

A

El Escorial criteria

For research purposes

39
Q

What tests do you do to rule out other conditions in MND?

A
Electromyogram
Nerve conduction studies
MRI of head and neck
Muscle Biopsy
Blood Tests
CSF tests
Consider DNA analysis
40
Q

Why might we do an MRI of head and neck on a suspected ALS patients?

A

Might be a tumour (speech problems)

41
Q

Is it common to do muscle biopsies in ALS-suspected patients?

A

No

42
Q

How should CSF tests be in ALS?

A

Normal

43
Q

TRUE or FALSE?

There are blood tests for ALS

A

FALSE

All they have found is increased CK (because of muscle wasting)

44
Q

Which is the most common gene associated with familial ALS and what are some other top ones?

A

C9orf72

SOD1 - 20%
FUS and TARDBP - each 5%
There are many others

45
Q

TRUE or FALSE?

Sporadic ALS is never associated with specific mutations

A

FALSE

A few have gene mutations like C9orf72

46
Q

What kind of penetrance does C9orf72 have?

A

Incomplete

47
Q

Which TARDBP is associated with ALS?

A

TDP43

48
Q

What is the relationship of ALS with other neuropathies and FTD?

A

ALS has involvement with upper and lower motor neurons while CMT only involves lower ones and hereditary spastic parapalesia upper motor neurones

Frontotemporal dementia overlaps with ALS quite a lot

49
Q

Why is there late diagnosis in MND?

A

It is often mistaken for something else

e.g. have to go to ENT clinics for trouble swallowing

50
Q

What are the cognitive features of MND?

A
Behavioural change
Emotional lability (not related to dementia)
Frontotemporal dementia
51
Q

Name the respiratory features of MND?

A
Shortness of breath on exertion
Excessive daytime sleepiness
Fatigue
Early morning headache
Un-refreshing sleep
Orthopnoea
Frequent unexplained chest infections
Weak cough and sniff
Nocturnal restlessness/ sweating
52
Q

What are supporting factors for MND diagnosis?

A

Asymmetrical features
Age - any age can present
Family history for MND or other neurodegenerative disease

53
Q

What are factors not supporting an MND diagnosis?

A

Bladder/bowel involvement
Prominent sensory symptoms
Improving symptoms

54
Q

What % of MND patient present with bulbar symptoms?

A

25%

55
Q

What % of MND patient present with limb features?

A

70%

56
Q

What are bulbar features of MND?

A
Dysarthria
Dysphagia
Excessive saliva
Chocking sensation when lying flat
Weak cough
57
Q

How can dysarthria present?

A

Quiet, hoarse or altered speech

Slurring of speech when tired

58
Q

What are limb features of MND?

A

Focal weakness - painless preserved sensation
Distal weakness
Muscle wasting - hands, shoulders, asymmetrical
Muscle twitching and dasiculations
Cramps

59
Q

How can distal weakness present?

A

Fall/trips - from foot drop

Loss of dexterity (problem with zip/buttons)

60
Q

Why do people with NMD have early morning headache?

A

They don’t breathe well at night

61
Q

Which muscles are least affected in MND?

A

Eye muscles

62
Q

How to care for someone with MND?

A

Care for person and those that matter around them

Improve quality of life and symptom control

Respect patient autonomy and choice

Emphasis on open and sensitive communication

63
Q

Describe the multidisciplinary care of patients with MND

A
Neurologist
MND nurse
Dietician
Occupational therapist
Physiotherapist
MND association
Respiratory physician
Psychologist
Speech and language therapist
Social worker
64
Q

Which symptoms in MND do we manage?

A
Muscle cramps
Spasticity
Respiratory symptoms
Depression
Cognition
Pain
Drooling
Dysphagia
Communication difficulties
65
Q

What is a feature that is dominant and difficult to manage in MND?

A

Fatigue

66
Q

Why might a person with MND have constipation?

A

Altered diet
Inadequate fluid
Lack of mobility

67
Q

How do we treat sialorrhoea?

A

Anticholingergic drugs

Non-pharmacological approaches

68
Q

Name some anticholinergic drugs

A

– Hyoscine (sublingual or transdermal)

– Atropine (orally)

– Tricyclic antidepressants (amitriptyline)

– Beta-blockers

– Glycopyrrolate

69
Q

Name some non-pharmacological approaches to treating sialorrhoea

A

– Salivary gland irradiation
– Salivary duct ligation
– Botulinum toxin

70
Q

How do we treat dysphagia?

A

Speech and language therapists

Dietitians

PEG (percutaneous endoscopic gastrostomy)

RIG (radiologically inserted gastrostomy)

71
Q

How do PEGs work?

A

A tube is put in so that food is delivered directly to the stomach and a light is used to guide this procedure

72
Q

When should patients get a PEG tube put in?

A

Earlier on - better survival

Because muscles must be preserved

73
Q

How should communication difficulties be treated?

A

Speech and language therapists

Communication aids

74
Q

What is used to treat muscle cramps?

A
  • Quinine
  • Diazepam
  • Phenytoin
  • Naftidrofuryl
75
Q

How do you treat spasticity?

A

Physiotherapy

Specific interventions e.g. low tech equipment, environmental control systems

Drug treatment

76
Q

What drugs treat spasiticity and what do they do?

A

– Baclofen
– Dantrolene
– Tizanidine

work by reducing excitability

77
Q

How do we treat respiratory symptoms?

A

NICE guidance

Non-invasive respiratory support - e.g. for nocturnal hypoventilation (rare)

symptomatic treatment - e.g. opioids

Breathing Space Kit (MNDA)

Invasive ventilation

78
Q

How do we treat depression and emotional lability?

A
  • Amitriptyline
  • SSRIs (selective serotonin re-uptake inhibitors) e.g. fluoxetine
  • Psychiatric guidance
79
Q

How do we treat pain?

A

• Anti-spasticity drugs

• Non-steroidal agents
Pain

  • Analgesics - including oral morphine or transdermal fentanyl patches
  • Principles of pain management include the WHO Ladder
  • Physiotherapy
  • Occupational therapy
80
Q

What kinds of care planning can be done in advance?

A
  • Advance directives
  • Palliative care
  • Multidisciplinary management
  • End of life care
  • Bereavement
81
Q

What is the only licensed disease modifying med for ALS?

A

Riluzole (glutamate release inhibitor)

82
Q

What are potential treatments for ALS?

A

Edaravone: Antioxidant treatment - only in Japan

Masitinib: tyrosine kinase inhibitor (targets mast cells and macrophages) - probably doesn’t work