Muscle And Nerve Disease Flashcards
What are the common presentations of muscle disorders (4)
Weakness of skeletal muscle (importantly respiratory and swallowing muscles)
Cardiac symptoms
Cramps/muscle pain/stiffness
Myoglobinuria (muscle breakdown product in urine)
What are the congenital classifications of muscle diseases (4)
Contractile (congenital myopathies)
Structural (muscular dystrophies)
Coupling (channelopathies)
Energy (metabolic dystrophies)
What are the aquifer classifications of muscle diseases (4)
Electrolyte disturbance (especially K+)
Endocrine (thyroid, adrenal, vitamin D)
Autoimmune inflammatory muscle disease
Latrogenic: medication (steroids/statins)
What investigations are important for muscle diseases (4)
Bloods (especially creatine kinase)
Electromyography (EMG)
Muscle biopsy
Genetic testing
What is myasthenia gravis
Disease characterised by rapid weakness and fatigue of any muscles under voluntary control (commonly affects eye muscles)
What is the presentation of myasthenia gravis
Fatiguable
Weakness:
occular:
- ptosis (drooping of eyelids)
- muscles of eye movement (Diplopia)
Generalised:
- limbs
- bulbar (chew, swallow, talk)
- breathing
What are the investigations for myasthenia gravis (3)
ACh receptor or anti-MuSK antibodies
Neurophysiology
CT chest (thyoma - cancer cells forming in the thymus)
What are the treatments for myasthenia gravis (symptomatic and disease modifying)
Symptomatic:
- cholinesterase inhibitors (decrease breakdown of acetylcholine)
Disease modifying:
- immunoglobulin/plasma exchange
- Steroids sparing immunosuppression
- thymectomy
What are the types of generalised peripheral neuropathy
Axonal vs demyelinating
What are the causes of peripheral neuropathy
Hereditary
Metabolic (diabetes, alcohol, renal failure, vitamin deficiency)
Toxic (drugs)
Infectious (Lyme, HIV)
Malignancy
Inflammatory
What is Guilin Barre syndrome
Autoimmune disease attacking nerves (usually post infection)
Initial symptoms are weakness and tingling in hands and feet
What are the investigations for peripheral nerve diseases (5)
Bloods
Electromyography (EMG)
Lumbar puncture (CSF analysis)
Nerve biopsy
Genetics
What is the treatment of peripheral nerve diseases
Treat the underlying cause (e.g stop drug, surgery, immunoglobulin)
What are the symptoms and signs of sensory pathologies
Loss of sensation/abnormal sensation
Pain
What are the symptoms and signs of motor pathologies
Muscle thinning
Weakness
What are the symptoms and signs of autonomic pathologies
Bowel
Bladder
Skin changes
Blood pressure
What is the clinical presentation of motor neurone disease (MND) (3)
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
How is MND diagnosed (3)
Combination of UMN and LMN signs
No sensory signs
10% have cognitive decline
What are common UMN lesion signs (3)
Spasticity
Brisk reflexes
Extensor plantars
What are common LMN signs (3)
Muscle fasciculations
Wasting
Weakness
What is the prognosis in MND
Median 3-5yr from symptom onset
2-3yrs from diagnosis
50% die within 14 months of diagnosis
What is the treatment for MND (3)
Supportive (physio, occupational therapy, PEG feed, non-invasive ventilation, speech and language therapy)
Rluzole (glutamate antagonist)
Anticipatory/palliative care
