Muscle And Nerve Disease

Question 1

What are the common presentations of muscle disorders (4)

Answer 1

Weakness of skeletal muscle (importantly respiratory and swallowing muscles)
Cardiac symptoms
Cramps/muscle pain/stiffness
Myoglobinuria (muscle breakdown product in urine)

Question 2

What are the congenital classifications of muscle diseases (4)

Answer 2

Contractile (congenital myopathies)
Structural (muscular dystrophies)
Coupling (channelopathies)
Energy (metabolic dystrophies)

Question 3

What are the aquifer classifications of muscle diseases (4)

Answer 3

Electrolyte disturbance (especially K+)
Endocrine (thyroid, adrenal, vitamin D)
Autoimmune inflammatory muscle disease
Latrogenic: medication (steroids/statins)

Question 4

What investigations are important for muscle diseases (4)

Answer 4

Bloods (especially creatine kinase)
Electromyography (EMG)
Muscle biopsy
Genetic testing

Question 5

What is myasthenia gravis

Answer 5

Disease characterised by rapid weakness and fatigue of any muscles under voluntary control (commonly affects eye muscles)

Question 6

What is the presentation of myasthenia gravis

Answer 6

Fatiguable
Weakness:

occular:
- ptosis (drooping of eyelids)
- muscles of eye movement (Diplopia)

Generalised:
- limbs
- bulbar (chew, swallow, talk)
- breathing

Question 7

What are the investigations for myasthenia gravis (3)

Answer 7

ACh receptor or anti-MuSK antibodies
Neurophysiology
CT chest (thyoma - cancer cells forming in the thymus)

Question 8

What are the treatments for myasthenia gravis (symptomatic and disease modifying)

Answer 8

Symptomatic:
- cholinesterase inhibitors (decrease breakdown of acetylcholine)

Disease modifying:
- immunoglobulin/plasma exchange
- Steroids sparing immunosuppression
- thymectomy

Question 9

What are the types of generalised peripheral neuropathy

Answer 9

Axonal vs demyelinating

Question 10

What are the causes of peripheral neuropathy

Answer 10

Hereditary
Metabolic (diabetes, alcohol, renal failure, vitamin deficiency)
Toxic (drugs)
Infectious (Lyme, HIV)
Malignancy
Inflammatory

Question 11

What is Guilin Barre syndrome

Answer 11

Autoimmune disease attacking nerves (usually post infection)
Initial symptoms are weakness and tingling in hands and feet

Question 12

What are the investigations for peripheral nerve diseases (5)

Answer 12

Bloods
Electromyography (EMG)
Lumbar puncture (CSF analysis)
Nerve biopsy
Genetics

Question 13

What is the treatment of peripheral nerve diseases

Answer 13

Treat the underlying cause (e.g stop drug, surgery, immunoglobulin)

Question 14

What are the symptoms and signs of sensory pathologies

Answer 14

Loss of sensation/abnormal sensation
Pain

Question 15

What are the symptoms and signs of motor pathologies

Answer 15

Muscle thinning
Weakness

Question 16

What are the symptoms and signs of autonomic pathologies

Answer 16

Bowel
Bladder
Skin changes
Blood pressure

Question 17

What is the clinical presentation of motor neurone disease (MND) (3)

Answer 17

First Symptoms tend to be limb weakness (often in ankle or leg - may trip more often or struggle climbing stairs)
Then bulbar symptoms (damage to lower cranial nerves e.g. difficulty swallowing, lack of gag reflex)
Then respiratory symptoms

Question 18

How is MND diagnosed (3)

Answer 18

Combination of UMN and LMN signs
No sensory signs
10% have cognitive decline

Question 19

What are common UMN lesion signs (3)

Answer 19

Spasticity
Brisk reflexes
Extensor plantars

Question 20

What are common LMN signs (3)

Answer 20

Muscle fasciculations
Wasting
Weakness

Question 21

What is the prognosis in MND

Answer 21

Median 3-5yr from symptom onset
2-3yrs from diagnosis
50% die within 14 months of diagnosis

Question 22

What is the treatment for MND (3)

Answer 22

Supportive (physio, occupational therapy, PEG feed, non-invasive ventilation, speech and language therapy)
Rluzole (glutamate antagonist)
Anticipatory/palliative care