Micro and Macro vascular complications of DM

Question 1

What are the micro-vascular complications of DM?

Answer 1

Retinopathy

Neuropathy

Nephropathy

All increase with poor control (high blood glucose levels) and duration of disease.

Question 2

What are the macrovascular complications of DM?

Answer 2

Stroke x 2

MI x 3-5

Amputation due to gangrene x 50

Treatment of DM only has a small effect on the macrovascular complications, but duration of disease and other risk factors are important factors.

Question 3

Describe the features of diabetic sensorimotor neuropathy?

Answer 3

• Affects lower limbs predominantly and affects sensory nerve more than motor nerves.
• Loss of sensation (fine touch, pain, vibration and proprioception*) in a glove and stocking pattern.
• Loss of ankle jerk and later knee jerk.
• Associated with poor glycaemic control and duration of disease.

*May not lose all modalities of sensation initially

Question 4

Describe the presentation of painful diabetic neuropathy?

Answer 4

• Often abrupt onset and not related to duration of diabetes may resolve completely.
• Burning foot pain, often worse at night.
• Associated with poor glycaemic control or occasionally associated with establishing good glycaemic control*.
• Management is with improving glycaemic control and analgesia for neuropathic pain (gabapentin, amitriptyline) *In this scenario it is self limiting.

Question 5

Describe the presentation of mononeuropathies in diabetes?

Answer 5

Neuropathy of a singular nerve often cranial nerves III, IV, VI.

Or of the deep peroneal L4/L5 nerve causing a foot drop.

Question 6

Describe the presentation of diabetic amyotrophy?

Answer 6

• Motor and sensory neuropathy.
• Severe pain and paraesthesiae in the upper legs, with weakness and muscle wasting of the thigh and pelvic girdle muscles.
• May be asymmetrical and there may be babinski +ve.
• Mainly affects middle-aged and elderly patients.
• Usually associated with a period of very poor glycaemic control, sometimes with dramatic weight loss.
• Pain and weakness gradually reduce once good glycaemic control has returned.

Question 7

Describe the presentation of autonomic neuropathy?

Answer 7

Affecting any part of the autonomic nervous system i.e:

• Cardiac
• GI
• Genitourinary

Cardiac: postural hypotension, exercise intolerance, increased incidence of MI

GI: nausea and vomiting, abdominal distension

GU: erectile dysfunction, incontinence.

Question 8

Describe the causes of diabetic foot disease?

Answer 8

Diabetics are a at risk of the complications of diabetic foot disease as they have:

1. Increased risk of peripheral arterial disease, therefore have poor circulation to peripheries.
2. Increased risk of peripheral neuropathy therefore are more likely to injure their feet without realising.
3. Furthermore they have an increased susceptibility to infections due to chronic hyperglycaemia providing a good environment for bacteria as well as hyperglycaemia causing a functional abnormality in neutrophills.

Question 9

Describe the complications associated with diabetic foot disease?

Answer 9

Diabetic patients can suffer from:

• Chronic foot ulcers, which never properly heal.
• Chronic foot ulcers can become infected and lead to osteomyelitis. May require amputation.
• May have peripheral arterial disease and gangrene.
• Charcot Foot: a neuro-arthropathic process with osteoporosis, fracture, acute inflammation and disorganisation of foot architecture.

Question 10

Describe the features of background retinopathy?

Answer 10

Dots, blots, superficial flame shape haemorrhages.

Microaneurysms.

Hard exudates.

Question 11

What are the features of pre-proliferative diabetic retinopathy?

Answer 11

Cotton wool spots,

Venous irregularities (bending of veins),

Dark blot hameorrhages,

Intraretinalmicrovascular abnormalaties (IRMA)

Question 12

What are the features of proliferative retinopathy?

Answer 12

Neovascularisation of disc (NVD)

Neovascularistaion elsewhere (NVE) (iris, retina)

Rubeosis Iridis. (new blood vessels around the iris)

Haemorrhage, vitreous/ pre retinal.

Question 13

What are the features of maculopathy?

Answer 13

Reduced acuity may be the only change.

May see hard exudates within the macula.

Question 14

When should a patient be referred to opthalmology?

Answer 14

Refer if pre-proliferative retinopathy / maculopathy

Question 15

How is diabetic retinopathy investigated and treated?

Answer 15

Ix:

• Slit lamp.
• Fluorescein angiography

Treatment:

• Laser photocoagulation
• Anti VEGF injections

Treatments prevent the proliferation of new vessels which are more likely to bleed.

Question 16

Which other eye condition is associated with DM?

Answer 16

Cataracts.

Question 17

What is the pathophysiology behind diabetic nephropathy?

Answer 17

• Glomerular hyperfiltration (hyperglycaemia thought to cause increased cell growth in the kidneys)
• Glomerular basement membrane thickening
• Expansion of mesanginal cells
• Nodular scelrosis

Essentially nephron loss and glomerulosclerosis

Question 18

Describe how best to prevent diabetic nephropathy?

Answer 18

Good glyacemic control and BP control.

ACEi is 1st line. BP should be 140/80 or 130/80 plus microvascular complications.