Motor Neurone Disease Flashcards
What symptoms is bulbar onset associated with?
- Loss of voice
* Swallowing problems
What symptoms do people with cognitive onset present with?
Fronto-temporal Dementia – aggressive, disinhibited
Name 4 high penetrance mutations in MND.
- C9orf72
- SOD1
- TARDBP
- FUS
What is MND?
An untreatable and rapidly progressive neurodegenerative condition
What type of diagnosis is MND?
Mostly clinical
What does MND present with?
Muscle weakness and wasting (secondary to motor neuron degeneration)
Potentially problems with speech, swallowing and breathing problems
To be MND, there must be what?
Upper +/- lower motor neurone signs, WITHOUT sensory problems
What is the onset and progression of MND like?
Focal onset, and continuous spread, then finally generalized paresis
MND exhibits various clinical __________?
PHENOTYPES
What is the most common type of MND?
Amyotrophic Lateral Sclerosis (ALS)
COGNITIVE IMPAIRMENT is a feature of MND.
TRUE
What is the average survival time with MND?
3 years
What is the lifetime risk of developing MND?
1 in 400
Is MND more common in males or females?
Males
What % of MND is sporadic?
90%
What % of MND is familial?
10%
What is the relationship between sporadic MND and age?
Sporadic MND peaks at the ages of 50-75 years, and declines after the age of 80
In what population is ALS less common in?
Non- Caucasian
Outline the UMN signs of MND.
- Increased tone
- Hyper-reflexia
- Extensor plantar responses
- Spastic gait
- Exaggerate jaw-jerk
- Slow movements
Outline the LMN signs of MND.
- Muscle wasting
- Fasciculations
- Weakness
- Absent or reduced reflexes
What % of cases of MND onset in the i) extremities ii) bulbar region iii) thoracic region?
i) 70%.
ii) 25%.
iii) 2%.
Of MND that begins in the extremities, is this more likely to be in the upper or lower extremities?
UPPER
At onset, what % of cases are associated with i) UMN ii) LMN iii) frontal/cognitive deficits?
i) 10%.
ii) 90%.
iii) 5%.
What is the most common MND phenotype?
ALS
Does ALS have UMN or LMN symptoms?
BOTH
Does primary lateral sclerosis have UMN or LWM symptoms?
UMN
Does progressive muscular atrophy have UMN or LMN symptoms?
LMN + subclinical UMN in 30%
Does ALS- frontotemporal dementia have LMN or UMN signs?
BOTH
Primary lateral sclerosis has a _____ prognosis
GOOD
There is a link between ALS and what type of dementia? What is this underpinned by?
Frontotemporal Dementia (FTD)
Underpinned by discovery of C9ORF hexanucleotide repeat expansions
What is ‘split hand syndrome’ in MND?
Preferential wasting of the thenar group a typical pattern of atrophy seen in ALS
What features must be present for a diagnosis of clinically definite ALS to be made?
- UMN and LMN signs in bulbar AND at least two spinal (lumbosacral, thoracic or cervical) regions
or
- UMN and LMN signs in three spinal regions
What features should be present for a diagnosis of clinically probable ALS to be made?
- UMN and LMN signs in at least 2 regions (bulbar or spinal), with some UMN signs rostral to the LMN signs
What are the features of clinically probably ALS (lab supported)?
- Clinical evidence of upper and lower motor neurone signs in one body region.
or - Of UMN signs in one region
AND
*EMG findings of LMN involvement in at least two body regions
What are the features of clinically possible ALS?
* UMN and LMN signs in only the bulbar or only one spinal region. or * UMN signs in two or more regions. or * LMN signs rostral to UMN signs
In what % of patients is there primary bulbar onset?
25%
Who tends to be affected by primary bulbar MND?
Women > men
60-80 years old
What always results from primary bulbar MND?
Generalisation into ALS
Suggest therapeutic interventions for primary bulbar MND.
Early communicator.
Nutritional support.
Care for URT.
A diagnosis of MND is a diagnosis of _________
EXCLUSION
What is the broad phenotype of MND due to?
- Site of onset
* Regions involved
What is the consensus clinical criteria for MND?
UMN signs +/- LMN signs WITHOUT any sensory symptoms
What are the potential types of MND?
- Classic MND (or Amyotrophic lateral sclerosis ALS)
- Progressive Muscular Atrophy (PMA)
- Primary Lateral Sclerosis (PML)
- Syndromes of MND and frontotemporal dementia (FTD-MND)
- Progressive Bulbar Palsy
- Flail Limb
State 3 frequent misdiagnosis of MND?
Carpal tunnel syndrome.
Stroke.
Neuropathy.
What UMN signs are associated with MND? (make sure to mention bulbar, cervical and lumbar region and abdominal region signs)
- Spasticity
- Babinski sign
- Bulbar UMN Signs:
Exaggerated snout reflex. Clonic Jaw Jerk. Emotional Lability. Forced Jaw Opening - Cervical and Lumbar Region:
Clonic Deep Tendon Reflexes. Preserved Reflex in a Weak, Wasted Limb. Hoffmann Reflex. Hyper-reflexia - Abdominal Region:
Loss of superficial abdominal reflexes
What medication is used in MND?
Riluzole
How are communication needs met in MND?
Speech therapy
* Technology from tablets to ‘voice banking’)
How are nutritional needs met in MND?
- Gastrostomy
* Dietetics
How are resp needs met in MND?
- Assessment
* Home ventilation
What have been identified as the pathological signature in 95% of cases?
TDP43 inclusions
Of the newly discovered causative monogenetic mutations, what is the most common?
The intronic hexanucleotide repeat expansion C9ORF72
What does C9ORF72 account for?
10% of the sporadic cases, and is very common in familial forms
What % of MND cases are now classified as monogenetic?
10-15%
