insulin + diabetes Flashcards
1
Q
diabetes mellitus
A
- caused by an insufficiency in the production or action of the pancreatic hormone insulin
- most common endocrine disorder
2
Q
type 1 diabetes
A
- loss of insulin production
- insulin dependent
- develops in children/young adults
- pancreas produces little or no insulin
- autoimmune disorder
3
Q
type 2 diabetes
A
- occurs when body is in insulin-resistant state and pancreatic beta cells cannot release sufficient insulin to compensate
- most common form
- diagnosed later in life
- result of lifestyle; obesity, lack of exercise, diet, genes
4
Q
hyperglycaemia
A
loss of insulin-stimulated glucose uptake
loss of insulin repression of gluconeogenesis and glycogen breakdown
5
Q
dyslipidaemia
A
loss of insulin repression of lipolysis (defect in production of lipid pathways)
6
Q
gestational diabetes
A
- can affect up to 25% of women during pregnancy
- usually develops in 2nd trimester and disappears after child is born
- cause not clear thought to be due to hormonal changes that may block action of insulin
7
Q
tests used to diagnose diabetes
A
- fasting glucose test
- glucose tolerance test
- HbA1c
8
Q
fasting glucose test
A
- no food or drinks except water for 8-10 hours
values:
normal: 3.9 - 5.4 mmol/L
prediabetes or impaired glucose tolerance: 5.5 - 6.9 mmol/L
diabetic: >7 mmol/L
9
Q
oral glucose tolerance test
A
- patient must fast for at least 8 hours
- plasma glucose measured immediately before and 2 hours after drinking 75g glucose dissolved in water
>11.1 mmol/L indicates diabetes
7.9 - 11 mmol/l indicates impaired glucose tolerance
10
Q
HbA1c
A
- HbA1c forms as a result of a slow and irreversible reaction between haemoglobin A (HbA) and glucose
- HbA1c levels measure the average blood glucose levels over the previous 3-4 months (average life-time of RBC)
- HbA1c levels indicate how well blood glucose is being controlled and can be used as diagnostic test for type 2
- > 48 mmol/l indicates type 2
- 42-47 mmol/l indicates a risk of developing diabetes
11
Q
diagnosis of diabetes
A
- diagnosis is made by classic acute symptoms of hyperglycaemia and an abnormal blood test
- in patients without classic symptoms diagnosis can be made by two abnormal blood tests on separate days
12
Q
acute symptoms of diabetes
A
- polyuria: excessive urination
- dehydration/increased thirst
- nausea/vomiting
- increased fatigue
- unexplained weight loss
- blurry vision
- poor wound healing because of damaged blood vessels
- genital itching/thrush
13
Q
polyuria in diabetes
A
excessive urination because the amount of glucose filtered by kidney exceeds maximal capacity for reabsorption, resulting in glucose entering urine and drawing H2O with it by osmotic diuresis
14
Q
diabetic ketoacidosis
A
- potentially life-threatening complication of type 1
- lack of insulin limits use of glucose as an energy source
- absence of insulin enhances free fatty acids (FFA) release from adipocytes
- FFAs converted to ketone bodies by the liver which can serve as energy source
- ketones cause the pH of the blood to become acidic
- liver continues to synthesise glucose - blood glucose rises
- high glucose in the urine takes water and solutes such as potassium and sodium with it - dehydration
15
Q
treatment of diabetic ketoacidosis
A
- fluid replacement, insulin, mineral replacement
- usually develops at the time of diagnosis, during illness, during growth spurt/puberty, when insulin hasn’t been taken correctly
