Diagnosis + Treatment of Disease- Glucose Metabolism Flashcards
What is diabetes mellitus?
Family of diseases characterised by relative or absolute deficiency of insulin
What is the difference b/w Type 1 + Type 2 diabetes?
Type 1 = absolute insulin deficiency- inadequate insulin secretion
Type 2 = relative deficiency- abnormal target cell responsiveness
What does insulin deficiency cause?
decreased utilisation of glucose, amino acids + fatty acids by peripheral tissues (particularly liver, muscle + adipose tissue)
How can insulin deficiency be tested for?
Hyperglycaemia
Glycosuria
Fructosamine
Hyperlipidaemia
Explain what fructosamine is + why it can be used to test for diabetes?
Formed by irreversible binding of glucose to serum proteins- reflects average blood glucose level over last 1-3wks
Higher the mean BG is overtime, higher the fructosamine
Explain how insulin replacement/ insulin receptor agonists can be used to treat diabetes?
Broken down in GI tract, only administered via injection, activates same response as endogenous insulin
What adverse effects may occur from exogenous administration of insulin?
Hypoglycaemia
Insulin resistance
Explain how insulin resistance may occur from exogenous administration of insulin?
Insulin Abs may attenuate responses to exogenous insulin, stress may induce insulin resistance by increasing secretion of adrenaline + corticosteroids, insulin receptor desensitisation/ down-regulation could lead to insulin resistance
How can hyperinsulinism (overdose of insulin) be treated?
- dietary + IV glucose
- Glucagon if not responding (IV)
Name another antidiabetic agent other than insulin
Sulphonureas (Glipizide)
Explain how Glipizide works?
- Partially blocks potassium channels
- Stimulates insulin secretion from B cells
- Can induce HYPOglycaemia (milder than insulin overdose)
What is the meaning of ‘insulinoma’?
Function tumour secreting insulin
What can insulinoma cause and why?
Hyperinsulinaemia + hypoglycaemia- normal -ve feedback mechanisms don’t work
