Hypoglycemia/insulinoma Flashcards Preview

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Flashcards in Hypoglycemia/insulinoma Deck (26):
1

Describe three things in Whipples Triad

– 1) symptoms/signs consistent with hypoglycemia

– 2) Low measured plasma glucose concentration

– 3) Resolution of symptoms/signs with increasing plasma glucose

2

Define hypoglycemia

Plasma glucose low enough to cause signs or symptoms including impairment of brain function. Typically < 70 mg/dl and whipples triad

3

What are some defenses against hypoglycemia?

release of glucagon by alpha cells to increase gluconeogenesis

decrease glucose clearance in kidney

decrease insulin

incrase ACh and NE

4

response of following hormones during HYPOglycemia

insulin

glucagon

epi

cortisol growth hormone

5

6

How does epinephrine increase glucose levels?

causes increase gluconeogeneis by liver

inhibits insulin release from beta cells

increase glycolysis from muscle and lipolysi from fat

7

What are Neurogenic symptoms of Hypoglycemia

 • Tremor • Palpitations • Anxiety/arousal • Sweating • Hunger

8

Neuroglycopenic sypmptoms of Hypoglycemia

• Cognitive impairment • Behavioral Changes • Psychomotor abnormalities • Visual changes • Seizures • Coma

9

What drugs can cause hypoglycemia?

insulinoma, nesidioblastosis, post gastric bypass

10

defiicency of which hormone can cause hypoglycemia?

cortisol

11

Critical illness such as _____ can cause hypoglycemia

liver/kidney/heart fail

sepsis

severe malnourishtmet

12

• Insulin secreting tumors of pancreatic origin that cause hypoglycemia

Insulinoma

13

14

• Occurs in 1‐4 people per million

• 1‐2% of all pancreatic neoplasms

• 90%: benign, solitary, intrapancreatic, < 2 cm

insulinoma

15

Where in the pancrease are insulinomas located?

Evenly distributed throughout the pancreas

16

When workig up a pt for insulinoma when do we get imaging?

 

Diagnosis made per hormonal studies when hypoglycemic. Imaging helps to localize an insulinoma after the diagnosis is made.

17

What is the gold standard test to dx insulinoma?

Supervised fast

• Provoke hormonal responses that maintain euglycemia

• Normally symptomatic hypoglycemia should not occur after a prolonged fast given gluconeogenesis

18

19

What are the parameters necesseary to dx Insulinoma in a supervised fast?

• End Points for the test

glucose ≤ 45 mg/dl

– Signs/symptoms of hypoglycemia

 Glucose ≤ 55 mg/dl + Whipple’s triad

20

Both proinsulin and C‐peptide are secreted with_____ insulin (including sulfonylureas) Neither Proinsulin or C‐peptide is contained within_____ pharmacologic insulin

endogenous

exogenous

21

what is the cutoff plasma glucose for insulinoma and regular people during fasting

55

you should be able to maintain euglycemia for up to 72 hours

22

YOu perform fasting test on pt. they have below normal glucose and INcreased insulin, what does this indicate?

isulin above 3 micro = insulinomas/ exogenous insulin/ sylfonlurease or autoimmune

**need to get C peptide!

23

Why do we order a C-peptide on pts with hypoglycemia and elevated insulin during a fasting test?

to tell if the insulin is endogeous (high C-peptide)= insluinoma or sulfynrueas

or exogenous (low C peptide)

24

Why do you need to ourder a sulfonulurea screen in pt with suspect insulinoma?

because both as the same lab values of hypoglycemia, incresaed insluin and increased C peptide

25

What do the B-hydroxybutyrate levels look lik in pt with insulinomas?

The are low but they shuld be HIGH in fasted states

26

When do we use the mixed meal test?

• Not standardized and validated like the 72 hour fast.

• Used to evaluate patients with postprandial symptoms following for example GI procedures such as Roux en Y gastric bypass surgery.