Lecture 23-Insulinoma Flashcards
Causes of hypoglycemia (5)
- sepsis
- malnutrition
- drugs
- liver failure
- renal failure
What are the reasons someone may have hypoglycemia outside of the hospital? (3)
- drugs like insulin
- hormonal deficiencies
- insulinoma
What do sulfonylureas and meglitinides do?
They’re drugs that could cause hypoglycemia
Sulfonylureas
bind the K receptor on beta cell pm to cause depolarization and constitutive release of insulin
From normoglycemia to severe hypoglycemia what are the steps the body takes to compensate?
- decrease insulin production
- increase glucagon and epi
- GH secretion increases
- cortisol rises
- adrenergic symptoms (sweating, anxiety, palpitations)
- neuroglycopenic symptoms (brain deprivation of blood glu causing cognitive dysfunction)
Whipples Triad
- <50 mg/dl glu
- neuroglycopenic symptoms
- symptom alleviation with glu
How do you determine the cause of hypoglycemia?
- rule out meds
- rule out hormonal deficiency (cortisol, TH)
- rule out hormonal overproduction (insulin)
How is insulinoma confirmed?
- 72 hr fast
- inappropriately high insulin levels during spontaneous hypoglycemia
How is a 72-hr fast performed?
- Begun by fasting and drinking only calorie-free and caffeine-free drinks
- when BG <45 mg/dl with symptoms of hypoglycemia
- at end correlate BG with insulin, proinsulin and Cpeptide
- test blood for sulfonylureas and megilitinides
Clinical symptoms of insulinoma (3)
- inappropriately high insulin
- fasting hypoglycemia
- neuroglycopenic symptoms
Is insulinoma generally malignant?
no-only in a very small number of people
All insulinomas are tumors of ______
islet cells
What are the therapies used to treat insulinoma if surgery is impossible? (4)
- diazoxide: prevents insulin release from beta cells
- IFN-alpha
- octreotide: somatostatin analogue
- Verapimil
