diabetes complications Flashcards
diabetes microvascular complications
retinopathy
nephropathy
neuropathy
gastroparesis
diabetes macrovascular complications
peripheral arterial disease
cerebral vascular disease
LHD
what is diabetes microangiopathy
diabetes of the small blood vessels
-histological hallmark is thickening of the capillary basement membrane with increased vascular permeability
pathogenesis of diabetic retinopathy
- hyperglycaemia increases retinal blood flow
- disrupts metabolism in retinal endothelial cell
- impaired vascular autoregulation, increased production vasoactive substances &endothelial cell proliferation
- decreased retinal blood flow
- capillary hypoperfusion and closure causes chronic retinal ischaemia so get production of VEGF_> vascular endothelial growth factor that further stimulates deleterious endothelial cell growth and increased vascular permeability (retinal leak and exudation)
risk factors for retionpathy
- long duration dm
- pregnancy
- poor glycaemic control
- hypertension
- hyperlipidaemia
- nephropathy/renal disease
- obesity and smoking
3 stages of retinopathy
non-proliferative
pre-proliferative
proliferative
signs of non-proliferative retinopathy
- microaneurysms
- retinal haemorrhages: dot and blot from microaneurysms that have burst or leak
pre-proliferative retinopathy signs and what causes them
- capillary hypoperfusion
- hard exudates: leaking of cholesterol through microaneurysms-macular oedema
- cotton wool spots: capillary infarct in nerve fibre layer
- venous beading
- intra-retinal microvascular abnormalities
signs of proliferative retinopathy
- neovascularisation
- vitreous haemorrhage
- retinal detachment
presentation of retinopathy
- loss of visual acuity if near macular
- sudden visual loss= vitreous haemorrhage or retinal detachment
what is good hba1c control
<53
mangement of retinopathy
- control
- ranibizumab which binds to VEG-A and is anti-angiogenic for dm macular oedema
- retinal photocoagulation (laser treatment)
- vitrectomy
what is the most common cause of end stage renal failure
diabetic retinopathy
pathophysiology progression of nephropathy and clinical sign for each stage
- microalbuminuria: thickened glomerular basement membrane, mesangium- increased GFR
- sustained proteinuria: glomerulosclerosis worsens, renal function worsens-GFRdecreases
- nephrotic range proteinuria
- renal failure
test that can be used for microalbuminuria
albumin: creatinine ration
males >30
females >20
management of nephropathy
- statins
- ACEI - for BP and reduce ang II vasoconstriction to decrease pressure
when are ACEI ci
Renal artery stenosis
diabetic neuropathy types
- somatic/ peripheral nervous system
- visceral autonomic system
- symmetrical sensory polyneuropathy
types of somatic nephropathy
- symmetrical sensory distal
- asymmetrical motor proximal
- mononeuropathy-mononeuritis multiplex
symmetrical sensory polyneuropathy
- often asymptomatic
- distal
- numb feet
- pain in lower limbs worse at night
- abnormal gait
- weakness and atrophy of interosseous muscles
what does symmetrical sensory polyneuropathy lead to
diabetic and charcot foot=rocker bottom foot
- claw toe due to loss of lateral and transverse arch
- calluses
- cant feel caluses so walk on them and get infected leading to ulceration
asymmetrical motor polyneuropathy symptoms
- severe and progressive weakness and wasting of the proximal muscles of lower and upper limbs
- pain
- hyperparaesthesia
- weight loss
- loss tendon reflex
prognosis and cause of asymmetrical motor polyneuropathy
usually acute infarction of LMN of lumbrosacral plexus so recovery usually in 12months however some deficits are permanent
mononeuropathy somatic which nerves are affected
- usually 3rd and 6th cranial nerves causing diplopia, femoral and sciatic nerves motor and sensory
- nerve compression palsies cause carpal tunnel synrome, polpiteal
features of autonomic neuropathy
- cardio: postural hypotension (drop to 30), tachycardia, fixed hr
- GI: dysphagia, gastroparesis, nocturnal diarrhoea, constipation
- genitourinary: difficulty micturition, erectile dysfunction , uti due to atonic bladder
- sudomotor: nocturnal sweats
- vasomotor: cold feet, dependent oedema
- pupillary: decreased pupil size
prognosis autonomic neuropathy
-10 years 50% dead from cardio resp arrest
causes of erectile dysfunction
- alcohol
- antihypertensives thiazide duretics
- beta blockers
- neuropathy diabetes and vascular
- depression
management for autonomic neuropathy ie for features above
- insulin
1. pain and paraesthesia - anticonvulsants
- antidepressants
- substance p deplete
- opiates
- membrane stabilisers
- antioxidants
2. postural hypo=fludrocortisone
3. gastroparesis: laxative or loperamide
4. atonic bladder=catheter
5. sweating: anticholinergic
6. erectile dysfunction: phosphodiesterase type 5 inhibitor
causes of a diabetic foot
- trauma in the prescence of neuropathy
- PAD ischaemia reduced healing
- infection cause ulcer under calluses
what is charcot neuro-arthopathy
- weakness and atrophy of interosseous msucle
- trauma to foot
- loss of transverse and lateral arch
- get claw toe
- inflammation cause joint dislocation and pathological fractures
- get rocker bottom foot
management dm foot
- educate
- microfilament
- foot pulses
- foot ulcer: boot and orthotics
