Diabetes Flashcards
What is the classic diabetes presentation?
Polyuria
Polydipsia
Lethargy/weakness
Weight loss/muscle wasting
Additional:
Ketones on breath
Vision blurring
UTIs (thrush) & skin infections
What are the differences between the presentation of type 1 and type 2 diabetes?
Type 1:
< 30yrs
Rapid onset
Diabetic ketoacidosis
Type 2: >40yrs Gradual onset Obese (central adiposity) Hyperosmolar non-ketotic syndrome
What symptoms does hyperglycaemia cause, and why?
Lack of glucose utilisation —> Tiredness, weight loss/muscle wasting —> ketoacidosis/hyperosmolar non-ketotic syndrome
Osmotic diuresis —> glucose has a high osmotic potential; pulls water out of glomerulus —> polyuria & polydipsia
Glucose feeds bacterial infections
What are some of the complications of diabetes?
MACROVASCULAR =
- cerebrovascular (stroke)
- cardiovascular (MI)
- peripheral vascular disease (claudication, gangrene)
MICROVASCULAR =
- retinopathy (haemorrhage, growth of vessels, occlusion of vessels)
- nephropathy
- neuropathy (erectile dysfunction, ulceration, diarrhoea/constipation)
What are the diagnostic criteria for diabetes?
Symptoms + 1 positive test
Asymptomatic + 2 positive tests
Fasting glucose > 7.0 mmol/L (oral glucose tolerance test = fasting + 120 min after taking glucose)
Random plasma glucose > 11.1mmol/L
HbA1c > 6.5% (glucose control over last 3 months)
What is the pathology cause of Type 1 diabetes?
Autoimmune (90%) or non-autoimmune (10%) destruction of beta-cells in the Islets of Langerhans leading to an absolute lack of insulin.
What is the pathology of Type 2 diabetes?
Insulin resistance (decreased sensitivity of insulin receptors) + Insulin deficiency (caused by glucose and FA causing glucotoxicity?) causing a relative lack of insulin
(hypersecretion of insulin initially, then insulin deficiency)
Describe the mechanism of diabetic ketoacidosis.
Lack of glucose utilisation causes starvation response
Lipolysis and fatty acid utilisation
Production of ketone bodies ( >5mmol/L)
Ketoacidosis
Fall in blood pH —> Increase in CO2 —> hyperventilation (shallow breathing leading to hypoxia)
+ hydrogen ions pushed into cells, displacing K+ into urine & vomit —> loss of fluids/electrolytes
Tachypnoea
COMA
DEATH
What is the treatment for Type 1 diabetes?
Subcutaneous insulin injection (daily/several times per day)
Exercise (reduce CVD risk)
Eat a balanced diet (reduce CVD risk)
Measure blood glucose levels frequently
Check feet, eyes, etc.
What is the treatment for Type 2 diabetes?
Lifestyle (balanced diet, stop smoking, increase exercise, reduce alcohol consumption to reduce CVD risk)
Biguanides e.g. metformin (increase insulin receptor sensitivity)
Sulphonylureas (increase insulin release)
Insulin
What are some of the reasons for poor blood glucose control in diabetic patients?
Peer-pressure/stigma
Over-exercise
Dieting/stopping insulin to lose weight
Mistake (forget to take insulin/take insulin too many times)
What are some other causes of diabetes apart from Type 1 & Type 2?
- genetic defects of beta cells/insulin action
- drug-induced (steroids, diuretics)
- Cushing’s syndrome, acromegaly (insulin resistance)
- haemochromatosis (bronze diabetes = excessive absorption/deposition of iron in organs)
- pancreatectomy (pancreatitis)
Give an example of another type of diabetes apart from diabetes mellitus.
Diabetes insipidus = deficiency of ADH causes excessive loss of water in urine, causing dehydration
What is the treatment and management for diabetic ketoacidosis?
Insulin
Replace fluids/electrolytes
What are the characteristics of diabetic neuropathy?
- sensation of walking on “cotton wool”
- weight of bedclothes irritating/painful
- helps getting up and walking around
- pins and needles + numbness
