L20 - Long term diabetic complications COPY

Question 1

COMPLICATIONS

i) name three microvascular complications
ii) name three macrovascular complications

Answer 1

i) retinopathy, nephropathy, neuropathy
ii) IHD, CVD and PVD

Question 2

MICROVASCULAR COMPLICATIONS

i) what is most cells response to high extracellular hyperglycaemia?
ii) name three types of cell that cannot protect themselves from high extracell hypergly (retina, glomerulus and nerve)
iii) how long do these complications take to develop?
iv) in what condition may they be detected at presentation? why?

Answer 2

i) can reduce glucose transport/wont internalise glucose

ii) cells that cant protect themselves from high glucose
- retinal endothelial cells
- mesangial cells of glomerulus
- schwann and peripheral nerve cells

iii) these complications take many years to develop
iv) may be detected at dx of T2DM because it often goes for a long time undiagnosed (5-10yrs)

Question 3

RETINOPATHY

i) what can it cause?
ii) how many x increase is the risk of blindness for those with diabetes?
iii) name two other eye conditions it also increases the risk of
iv) how dense are retinal capillaries? what does this mean
v) which cells are key to local regulation of blood flow? how do they do this

Answer 3

i) second most common cause of blindness in people of working age
ii) 10-20x increased risk of blindness if have diabetes
iii) glaucoma and cataracts
iv) low density of capillaries in the retina means there is little functional reserve

v) pericytes are key to regulating blood flow
- have contractile function and wrap around capillaries and direct blood flow where needed

Question 4

PATHOLOGICAL FINDINGS OF DIABETIC RETINOPATHY

i) what cells are lost?
ii) what happens to the basement membrane under the capillaries? what does this impair?
iii) what does capillary collapse cause in the retina?
iv) what does the retina release in response to capillary collapse? what does this then cause
v) what can leak out of vessels and form a hard exudate?(2)
vi) what is seen as ‘cotton wool spots’ on retinography?

Answer 4

i) loss of pericytes
ii) basement membrane thickens which impairs diffusion of molecules to the retina
iii) capillary collapse can cause ischaemia
iv) the retina releases VEGF in response to ischaemia which can increase cap permeability and cause leakage
v) fluid and cholesterol
vi) ischaemia

Question 5

RETINOPATHY

i) what is seen in A? what may this cause?
ii) what has happened in B? how may this be treated?
iii) what are the white spots on C?
iv) what are the white spots on D?

Answer 5

i) fibrous scar on the back of the retina - may cause detachment of the retina

ii) catastrophic bleed into the vitreous humour
- do a vitrectomy and replace it with salone

iii) ischaemia
iv) exudate

Question 6

SCREENING FOR RETINOPATHY

i) how may vision be affected with complex disease?
ii) what is used to take a photo of the eye/retina?
iii) how many fields are taken from each eye?
iv) what is shown by the arrow? how advanced is this eye disease? what may it be associated with?

Answer 6

i) can still have normal vision even in very complex disease
ii) use a high resolution digital camera
iii) take two fields from each eye

iv) new vessels are growing over the iris
- advanced eye disease
- can be assoc with glaucoma

Question 7

CLINICAL STAGES OF RETINOPATHY

i) name three things that may be seen in non proliferative retinopathy
ii) what may changes in proliferative retinopathy be due to? what action should be taken?
iii) name one other consequence of retinopathy

Answer 7

i) dots, haemmorhage, microaneurysms, hard exudate

ii) prolif changes due to ischaemia
- refer to an opthalmologist

iii) macular oedema (can be sight or non sight threatening)

Question 8

DIABETIC RETINOPATHY

i) what parameter can accelerate disease progression?
ii) name one treatment - which two ways can this be given
iii) what treatment can be injected into the vitreous? how does this work?

Answer 8

i) high blood pressure

ii) laser treatment
- can be pan retinal (everywhere but macula) or focal

iii) intra vitreal anti VEGF antibody
- agents against VEGF (which drives angio and leaky bv)

Question 9

NEUROPATHY

i) what % of diabetic patients may this affect?
ii) what % have painful neuropathy?
iii) name three types of neuropathy

Answer 9

i) up to 50% of diabetic patients
ii) 15% have painful neuropathy
iii) peripheral, mono and autonomic

Question 10

PERIPHERAL NEUROPATHY

i) name three symptoms
ii) what is the effect on motor nerves? what is particularly seen in the hands?
iii) what is the common distribution?
iv) which nerves are the most affected?
v) is most damage proximal or distal?

Answer 10

i) tingling, numbness, burn, electric shock

ii) affects motor nerves which causes muscle weakness
- see interossus wasting in the hands

iii) symmetrical stocking and gloves distribution
iv) longest nerves are most affected
v) damage is distal more than proximal

Question 11

NEUROPATHY FOOT PROBLEMS

i) what single thing do you need to develop a neuropathic ulcer?
ii) name three characterstics of a neuropathic ulcer
iii) how do neuropathic ulcers start of?
iv) what acute foot problems are diabetics also at risk of? what kind of process occurs here? what is the result?
v) how is the above acute problem treated?

Answer 11

i) nerve damage
ii) on a pressure area, callus build up and soft tissue necrosis
iii) ulcers start off as a callus

iv) diabetics also at risk of charcot foot
- inflammatory process due to dense nerve damage
- makes joints and bones vulnerable -> fractures and foot deformity

v) treat charcot foot by putting it into a cast and stop weight bearing on the foot

Question 12

MONONEUROPATHY

i) what single nerve does this affect?
ii) name two symptoms
iii) how many weeks does it take to reverse?
iv) which two other symptoms may accompany this

Answer 12

i) CN III (oculomotor nerve)

ii) ptosis (eye down and out - can be partial)
- pupil dilation (only if surgical)

iii) always reverses in 12 weeks
iv) can also get foot and wrist drop

Question 13

AUTONOMIC NEUROPATHY

i) how is stomach emptying affected? what is this called? how does this leave the person feeling?
ii) what type of hypotension may be seen? why?
iii) what type of sweating may be seen?
iv) name two other symptoms
v) can the underlying cause be treated?

Answer 13

i) impaired emptying = gastroparesis
- leaves patient feeling full and bloated

ii) postural hypotension as the ANS cant maintain BP
iii) gustatory sweating (sweat when eating)
iv) dirhoea and erectile dysfunction
v) cant treat nerve damage so have to treat the symptoms

Question 14

NEPHROPATHY

i) what is the most common cause of end stage renal disease in the western world?
ii) which patients are likely to die earlier if they get nephropathy
iii) name the three components of the filtration barrier in the kidney

Answer 14

i) diabetes
ii) T1DM patients
iii) fenestrated glom capillaries, basement membrane and podocytes

Question 15

DIABETIC NEPHROPATHY - PATHOL FINDINGS

i) how does the basement membrane change? how is the charge affected and what does this cause?
ii) which type of specialised cells are lost? what does this lead to
iii) name two things that occur that further decrease renal function
iv) what is one of the first things seen in this pathology?

Answer 15

i) thickening of BM
- loss of negative charge which usually helps it repel proteins
- loss of charge allows proteins through

ii) loss of podocytes
- leads to loss of integrity of the filtration barrier

iii) glomerular sclerosis and mesangial expansion further decrease renal function
iv) leaking protein (albumin)

Question 16

CLINICAL STAGES OF DIABETIC NEPHROPATHY

i) what is the hallmark of diabetic kidney disease?
ii) which two stages of albuminuria will be dipstick negative? which stage will be dipstick positive?
iii) at what stage is GFR declining?
iv) name two ways that microalbuminuria can be reversed

Answer 16

i) protein in the urine

ii) normo and microalbuminuria are dipstick neg
albuminuria is dipstick positive

iii) declining GFR at dipstick pos albuminuria
iv) microalbumin cna be reversed by controlling glucose and BP

Question 17

DIABETIC NEPHROPATHY TX

i) what is it most important to control?
ii) which two drug classes are preferred?
iii) nephropathy is associated with increased risk of which macrovascular disease?
iv) what may ultimately need to happen to these patients?

Answer 17

i) blood pressure
ii) blockers of the RAS system eg ACEIs and ARBs
iii) incerased risk of CVD
iv) renal replacement and transplantation

Question 18

DIABETES AND MACROVASCULAR DISEASE

i) patients with which type of diabetes have lots of risk factors
ii) which study showed that diabetes have a high level of modifiable RF for CVD?
iii) do patients with T1DM get metabolic syndrome?
iv) name three macrovasc disease presentations in diabetic patients
v) name four main modifiable risk factors

Answer 18

i) T2DM (metabolic syndrome)
ii) interheart study
iii) no
iv) CVD, stroke and peripheral vasc disease
v) smoking, glucose control, BP and lipid profile

Question 19

THE DIABETIC FOOT

i) what is it the most common cause of?
ii) name three things that can cause it in the context of diabetes
iii) why may antibiotics not be that effective?

Answer 19

i) most common cause of non traumatic lower limb amputation
ii) PVD (impaired blood flow to limbs), neuropathy (neuropathic ulcer), impaired WBC function
iii) poorly perfused so antibiotics wont really reach it

Question 20

UKPDS & DCCT

i) what condition is UKPDS a study of?
ii) what did it show?
iii) what condition is DCCT a study of?
iv) what did it show?

Answer 20

i) T2DM
ii) showed that tight control of glucose and blood pressure resulted in less microvascular complications
iii) T1DM
iv) higher HbA1c increased the risk of all microvasc conditions, especially retinopathy