Polyneuropathies

Question 1

What is the most common initial presentation for a polyneuropathy?

Answer 1

1. Distal symmetrical polyneuropathy

2. Glove and stocking distribution

Question 2

Which three causes of polyneuropathy should be considered if these individual factors were present?

1. Diarrhoea and vomiting
2. Weight loss
3. Arthralgia

Answer 2

1. GBS
2. Cancer
3. Connective tissue disease

Question 3

What are the causes of sensory polyneuropathy?

Answer 3

Diabetes mellitus, CKD, chronic alcohol

Question 4

What are the causes of motor polyneuropathy?

Answer 4

GBS, Charcot-Marie-Tooth

Question 5

How should you investigate a polyneuropathy?

Answer 5

1. FBC, ESR, CRP, U&Es, LFTs, HbA1c, bone profile, B12, folate, serum electrophoresis, vasculitis screen, CK.
2. Nerve conduction studies
3. Needle electromyography

Question 6

What do nerve conduction studies differentiate between in polyneuropathy?

Answer 6

Demyelinating (20%) vs axonal (80%) pathology

Question 7

What does needle electromyography exclude in polyneuropathy?

Answer 7

Myopathy and NMJ disease

Question 8

What is the commonest inherited polyneuropathy and what is its inheritance pattern?

Answer 8

1. Charcot-Marie-Tooth disease

2. Autosomal dominant

Question 9

What is this a presentation of?
Starts in puberty, weak legs, foot drop, and variable loss of sensation and reflexes. Distal wasting (champagne bottle legs), high arched foot, atrophy of hand muscles.

Answer 9

Charcot-Marie-Tooth disease