Neuropathies Flashcards
Which types of nerve fibres are the largest? (2)
Motor fibres, and sensory fibres for touch, vibration, position and proprioception
What happens when large motor fibres (LMN) are damaged?
Symptoms of weakness, muscle wasting, reduced power and absent reflexes
Symptoms of autonomic dysfunction (and which type affected) (5)
Postural hypotension (S) Erectile dysfunction (P) Nausea and vomiting due to gastroparesis (P) Horner's (S) Holmes-Adie pupil (P)
In what situation would the sensation of pin prick and temperature be reduced?
When small sensory fibres are damaged
What is a “neuropathic” gait?
High stepping gait
Describe the pattern of length dependent neuropathy
“Glove and stocking”- “rolls up” the legs and arms as the severity increases
Most commmon cause of a glove and stocking distribution of sensory loss/weakness
Diabetic neuropathy
Damage to one of more peripheral nerves, usually in association with a systemic cause (WARDS PLC?)
Mononeuritis multiplex
Two common causes of mononeuritis multiplex
Diabetes mellitus
Rheumatoid arthritis
Differential diagnosis of carpal tunnel syndrome
C8 radiculopathy
Acute inflammatory demyelinating polyneuropathy, often following an infection
Guillain-Barre syndrome
What are the symptoms of Guillain-Barre syndrome? (1)
Progressive ascending paraplegia
Management of Guillain-Barre syndrome (2)
IV immunoglobulin and plasma exchange
25% require mechanical ventilation
Causes of death in Guillain-Barre syndrome (2)
Cardiac arrhythmias due to autonomic failure
Type 2 respiratory failure
Two chronic demyelinating neuropathies
Chronic inflammatory demyelinating polyradiculopathy
Charcot-Marie-Tooth disease
How does Charcot-Marie-Tooth present?
In puberty with weak legs and foot drop with variable sensory/reflex loss; also causes atrophy of hands and legs
Inheritance of CMT disease
Most common mutation is inherited autosomal dominantly
Treatment of vasculitic axonal neuropathies
Prednisolone + cyclophosphamide
Treatment of demyelinating inflammatory neuropathies
IV immunoglobulin, steroids, DMARDs
Mostly motor polyneuropathies (3)
CMT
Lead poisoning
Guillaine Barre
Mostly sensory polyneuropathies (3)
Diabetic
Renal failure
Leprosy
