Diabetic Neuropathy

Question 1

What is lost in diabetic neuropathy

Answer 1

both myelinated and unmyelinated nerve fibres

Question 2

What are the fibres that are affected in diabetic neuropathy

Answer 2

distal sensory and autonomic fibres

Question 3

What is likely to contribute to the pathogenesis of diabetic neuropathy

Answer 3

Metabolic and vascular factors and impaired nerve repair mechanisms

Question 4

what are some of the metabolic risk factors

Answer 4

Advanced glycosylation end products (AGEs)
Sorbitol
Oxidative stress

Question 5

What is sorbitol

Answer 5

a product that is formed when glucose enters cells and is metabolised by the enzyme aldose reductase

Question 6

How does sorbitol have an effect on diabetic neuropathy

Answer 6

an accumulation of intracellular sorbitol in tissues such as peripheral nerves results in a rise in cell osmolality, a decrease in intracellular myoinositol and Na-K-ATPase activity and a slowing of nerve conduction velocities

Question 7

Levels of what are reduced in peripheral micro vessels from diabetic patients

Answer 7

thrombomodulin and tissue plasminogen activator levels

Question 8

How might diabetic neuropathy manifest as

Answer 8

distal symmetrical polyneuropathy
polyradiculopathy
mononeuropathy
autonomic neuropathy

Question 9

What is the most common form of diabetic neuropathy

Answer 9

Distal symmetrical polyneuropathy

Question 10

How do patients present with distal symmetrical polyneuropathy

Answer 10

distal sensory loss or paraesthesia (sensation of numbness, tingling,, burning or sharpen that starts in the fee and spreads proximally

Question 11

What are the signs of distal symmetrical polyneuropathy

Answer 11

loss of pinprick
termperature
virbation and joint position sensation
diminished ankle reflexes

Question 12

What is diabetic polyradiculopathy characterised by

Answer 12

severe pain in the distribution of one or more nerve roots

Question 13

Does diabetic polyradiculopathy ever resolve

Answer 13

yes - usually over 6-12 months

Question 14

What are the sensory symptoms in polyradiculopathy sometimes accompanied by

Answer 14

Muscle weakness

Question 15

What is the most common presentation of mononeuropathy

Answer 15

ptosis and ophthalmoplegia due to CNIII palsy

Question 16

What does autonomic neuropathy usually involve

Answer 16

Multiple systems including:
Cardiovascular: tachycardia, postural hypotension, neuropathic oedema
GI: gastroparesis, anorexia, nausea, vomiting
Genitourinary: bladder dysfunction, erectile dysfunction, retrograde ejaculation, reduced libido
Hypoglycaemia unawareness: reduced adrenaline release results in a loss of the adrenergic symptoms of hypoglycaemia

Question 17

What must be examined to assess sensory function

Answer 17

Pinprick, temperature, vibration and pressure sensation must be examined

Question 18

What are the most sensitive tests for the diagnoses of diabetic neuropathy

Answer 18

nerve conducting studies an autonomic testing by using HR change during the Valsalva manoeuvre

Question 19

How can we control neuropathic pain

Answer 19

tricyclic antidepressents (amitriptyline)

Question 20

What is a major side effect of amitriptyline

Answer 20

sedation

Question 21

What can be used to reduced the accumulation of sorbitol in nerve cells

Answer 21

aldose reductase inhibitors

Question 22

What should be considered for patients with carpal tunnel syndrome

Answer 22

surgical decompression

Question 23

What is the medical treatment of postural hypotension

Answer 23

increaseing the plasma volume with flrudrocortisone , a high salt diet and adequate hydration

Question 24

How can we minimise the symptoms of gastroparesis

Answer 24

more frequent, smaller meals that are easier to diegest and are low in fat and fibre

Question 25

What is the treatment of diabetic autonomic enteropathy

Answer 25

``` Loperamide (diabetic diarrhoea in acbsence of bacteria) rotating antibiotics (for bacterial overgrowth) stool softeners (constipation) ```

Question 26

What is the treatment of bladder dysfunction

Answer 26

Strict voluntary urination schedule Bethanechol (increases detrusor muscle contraction) Self catheterisation Resection of the internal sphincter at the bladder neck

Question 27

What should be given for diabetic men with erectile dysfunction

Answer 27

oral sildenafil

Question 28

How can clinically detectable neuropathy be reduced in both type 1 and type 2 diabetics

Answer 28

Tighter glycaemic control

Question 29

Type1 diabetics are more prone to developing neuropathy. True or False

Answer 29

True