5: Peripheral neuropathy Flashcards
What is an endocrine disease which causes peripheral neuropathy?
Diabetes
What happens to the reflex response when peripheral nerves are damaged?
Reduced/absent reflexes
What are some symptoms of autonomic neuropathy?
Sweating
Tachycardia
Gastroparesis
What is dyesthesia?
Pain on touching caused by peripheral nerve damage
Neuropathy of which nerve causes a high-stepping gait?
Why?
Deep fibular nerve
Responsible for foot dorsiflexion, so patient has to lift foot high to prevent dragging foot
What is the most common mononeuropathy?
Carpal tunnel syndrome
Mononeuritis multiplex is (symmetrical / asymmetrical).
asymmetrical
Peripheral neuropathy tends to be (symmetrical / asymmetrical).
symmetrical
What sort of distribution does diabetic peripheral neuropathy often take?
Glove and stocking
In which two ways can large diameter nerve fibres be damaged?
Axonal loss (e.g infarction, trauma)
Demyelination
What is a common acute-onset demyelinating neuropathy?
Guillain Barre syndrome
What are the symptoms of GBS?
Progressive loss of sensation in limbs
Tingling pain
When do symptoms peak in GBS?
2 weeks after onset
What can be absent in GBS?
Reflexes
1 in 4 GBS patients require ___.
ventilation
How is Guillain Barre syndrome treated?
Admission to hospital
IV immunoglobulins (to buffer immune system)
Plasmapharesis (filtering of blood to strip out demyelinating substances)
What is a less common type of demyelinating neuropathy?
Hereditary motor and sensory neuropathy (HMSN)
What are common presentations of HMSN?
Just memorise:
LOWER LIMB MUSCLE WASTING (tibial / fibular nerve)
CLAW HAND (ulnar nerve)
HIGH ARCHED FOOT (imbalance between leg and foot muscles)
What are some causes of peripheral neuropathy?
Infection
Drugs/Alcohol
Neoplasia
Vasculitis
Diabetes, vitamin deficiencies, porphyria…
What are need-to-know causes of autonomic neuropathy?
Diabetes
Amyloidosis
HMSN
GBS
Porphyria
A patient presents with an acute abdomen and peripheral neuropathy.
What is the likely diagnosis?
Porphyria
A patient has tingling and muscle wasting over their thenar eminence.
What neuropathy do they have?
Carpal tunnel syndrome
Caused by compression of the median nerve within the carpal tunnel
Describe two tests which can elicit carpal tunnel symptoms.
Phalen’s test: ask patient to do reverse prayer sign
Tinel’s test: tap on the carpal tunnel with your finger or a tendon hammer
A patient describes a lack of sensation over their “regimental badge patch” area.
Which nerve is involved in this peripheral neuropathy?
Axillary nerve
A patient experiences facial weakness.
Which nerve is involved in this neuropathy?
CN V
FOREHEAD SPARING - UMN disease (e.g a stroke)
NO FOREHEAD SPARING - LMN disease (Bell’s palsy)
A patient presents with wrist drop.
Which nerve is likely involved in this peripheral neuropathy?
Radial nerve
A patient presents with a claw hand.
Which nerve is likely involved in this peripheral neuropathy?
Ulnar nerve
A patient presents with a hand of benediction.
Which nerve is likely involved in this peripheral neuropathy?
At which point in the upper limb is it damaged?
Median nerve
Forearm or elbow (because it’s not a carpal tunnel syndrome)
