Pathology of DM complications Flashcards
How much of pancreatic islet cells are B cells?
2/3rds
Pathology of T2DM is a combination of….
- reduced tissue sensitivity to insulin (insulin resistance)
- inability to secrete very high levels of insulin
Increase in FFA effect on insulin
Leads to decreased insulin receptor sensitivity
What does central adiposity lead to and why?
Hyperinsulinaemia
More insulin needs to be produced to make glucose go back to normal levels as decreased removal of glucose from the blood
Annual mortality % of diabetics compared to non diabetics
5.4%
double the rate of non diabetics
How much is life expectancy decreased by in DM?
5 - 10 years
What does DM accelerate in large vessels and therefore they are at a higher risk of what?
Atherosclerosis so at a higher risk of
- CHD
- MI
- atherothrombotic stroke
How does DM accelerate atherosclerosis?
Glucose attaches to low density lipoprotein
Glucose molecules stop low density lipoprotein from binding its receptor (on liver cells) tightly
Low density lipoprotein is not removed by liver cells -> lipoprotein and lipid stay in blood -> hyperlipidaemia
Hyperlipidaemia leads to atherosclerosis
How does DM cause arteriolar disease?
Molecules flux into subendothelial but find it hard to flux back to the blood.
Build up of ‘trapped’ molecules under endothelial cell
Basal lamina also becomes thickened
Narrow arteriole - poor blood flow - ischaemia
Risk of amputation in DM
40x
`Risk of end stage renal disease in DM
25x
Risk of blindness in DM
20x
Pathology of small vessel disease in DM
Increase connective tissue around capillaries e.g. glomerulus in kidney
Collagen is glycosylated which binds to albumin (doesn’t bind usually) and albumin accumulates in subendothelial spaces of arterioles
Protein structure in DM small vessels and what does this mean?
Proteins are cross linked
Rigid, cross-linked proteins cannot easily be removed
They persistent even if return to normoglycaemia
2 results of glycosation
Accumulation of trapped plasma proteins
Accumulation of cross linked basal lamina proteins
Treatment of sensory neuropathy
Painkillers Gabapentin Duloxetine Acupunture More
What type of pulse tends to be bounding? Why do we have to beware of this?
Neuropathic pulse
As can have good pulse but poor perfusion
How are calluses related to ulcers?
Pressure causes callus formation
If the callus gets too hard then can break down the tissues underneath it
What are involuted nails?
Gentle curves to a pincer shape
When is there a big ulcer risk under calluses?
Neuropathic
Presentation of Charcots
Rockerbottoms foot Clawing of toes Bounding pulses Possible 3C temperature difference between the feet Look for infection
What is charcots a combination of?
Osteopenia
Sensory neuropathy
Trauma
What type of condition is charcots?
Inflammatory
Examples of GI autonomic neuropathies
Chronic diarrhoea
GORD
Gastroporesis
What is GORD caused by?
Reduced LOS pressure
When does chronic diarrhoea as a result of autonomic neuropathy often occur?
At night
Features of gastroparesis
Erratic BG control
Bloating
Vomiting
Treatment of gastroporesis and what kind of drugs are these?
Metoclopramide
Domperidone
Erythromycin
PROKINETIC DRUGS
