Endocrine Pancreas Path Singh

Question 1

What regulates glucose homeostasis?

Answer 1

• hepatic release of glucose
• tissue utilization of glucose
• hm control of glu by insulin and glucagon

Question 2

What is a marker of endogenous insulin? what is the significance of this?

Answer 2

C peptide, it allows you to tell the difference between insulin administered vs made by self

Question 3

What is type 1 diabetes? When do symptoms occur?

Answer 3

• Autoimmune disease due to failure of T cell self tolerance
• Immune mediated destruction of islet cells → once 90% of islet cells are destroyed you begin to get sx

Question 4

What causes type 2 DM?

Answer 4

Insulin resistance + Beta cell dysfunction

Question 5

Why is obesity a risk for T2DM?

Answer 5

• excess adipose results in free fatty acids, inflammation, and adipokines accumulating
  
  • adipokines and ffa disrupt paths that enable insulin uptake
  • inflammation causes direct damage to beta cells and can also disrupt cell uptake of insulin

Question 6

What is MODY? Cause?

Answer 6

• maturity onset diabetes of the young
• Resembles T2DM clincally but happens in the young, blood insulin may be high normal or low
• NO autoantibodies
• nonketotic
• Most often caused by mutations resulting in los of function of glucokinase

Question 7

Risks to the fetus if mom has gestational diabetes?

Answer 7

• neonatal hypoglycemia → seizure → brain damage
• macrosomia
• congenital malformation
• still birth

Question 8

Classic triad of T1DM?

Answer 8

• polyphagia
• polyuria
• polydipsia
• severe → DKA

Question 9

How do you differentiate T1DM and T2DM?

Answer 9

• autoantibodies
  
  • 90% white kids have
  • <50% west african descent and Latinx populations have, so it is difficult to tell 1 from 2
• HLA typing
  
  • HLA DR/DQ on chr 6

Question 10

DKA triad?

Answer 10

• hyperglycemia
• ketonemia
• metabolic acidosis

Question 11

How does epinephrine impact glucose?

Answer 11

Body can’t use glucose so it accumulates in the blood

Question 12

How does a stressful situation (infections) induce DKA in a diabetic patient?

Answer 12

• With high epinephrine the body isn’t able to utilize glucose
• Glucagon gets released promoting gluconeogenesis
• Insulin deficiency promotes FFA generating ketones
• as glucose and ketones accumulate in blood kidneys begin to dump that → osmotic diuresis
• leading to shock and dehydration which causes more epinephrine to be released repeating the cycle

Question 13

How do you test for DKA?

Answer 13

Accumulation of ketones in the urine

Question 14

What is Hyperglycemic Hyperosmotic syndrome? What are the symptoms?

Answer 14

• acute hyperglycemic crisis in T2DM resulting from a prolonged insulin deficiency
  
  • increased gluconeogenesis
  • decreased glucose uptake in peripheral tissue
• Glucose >600
• severe dehydration
• Hyperosmolality → coma
• Impaired renal fxn
• NO ketones

Question 15

Compare DKA and HHS.

• anion gap acidosis
• osmolality
• hyperglycemia
• ketonemia

Answer 15

Question 16

what is Hemoglobin A1C, what is the use, and target?

Answer 16

• glycosylated form of hemoglobin that takes a month to form
• it measures long term diabetic control
• target is <6.5-7.0

Question 17

What are the risks assoc. with chronic hyperglycemia?

Answer 17

• stroke
• MI (most common COD)
• lower extremity gangrene (100x higher risk)

Question 18

Advanced glycatedd end products?

Answer 18

• breakdown product of glucose
• modify and crosslink proteins (makes it abnormal) as they accumulate and they can act on receptors in endothelial cells to create cellular dysfunction and damage

Question 19

What is the leading cause of ESRD in the US?

Answer 19

Diabetic nephropathy

Question 20

What are the three primary pathologic conditions seen in diabetic nephropathy?

Answer 20

• Glomerular sclerosis:
  
  • thickening of basement membrane
  • disruption of protein cross links that make membrane effective filter → leak large molecules into urine
• Renal vascular lesions:
  
  • arteriolosclerosis
• Pyleonephritis

Question 21

What are the pathologic changes seen in diabetic nephropathy?

Answer 21

• Nodular mesangial matrix accumulation in glomeruli called Kimmelstiel Wilson disease
• Also grossly see diffuse nephrosclerisis due to the underlying microscopic changes

Question 22

How do you test for diabetic nephropathy

Answer 22

Urine albumin Creatinine ratio testing is the gold standard (UACR)

Question 23

Describe neovasculariztion seen with diabetic retinopathy?

Answer 23

• Hypoxia leads to VEGF overexpression →
• Hemorrhage →
• Blindness

Question 24

Besides diabetic retinopathy what are other occular complications of diabetes?

Answer 24

Cataracts and glacuoma

Question 25

Commonalities between Pancreatic neuroendocrine tumors?

Answer 25

* solid yellow tan * predilection for neck and tail * well differentiated neuroendocrine tumors * secretory granules

Question 26

Describe an insulinoma * involved cell * metastasis * clinical presentation * gross/histo

Answer 26

* Beta cells * 10% mets * hypoglycemia * small tumors less than 2cm produces symptomatic hypoglycemia * amyloid is common on histo

Question 27

Gasstrinoma presentation and triad?

Answer 27

* Islet cell tumor * Gastric acid hypersecretion * Peptic ulceration * DO NOT respond to therapy

Question 28

Somatostatinoma presentation?

Answer 28

* Diabetes, cholelithiasis, steatorrhea * silences beta cells leading to reduced insulin * reduces gallbladder motility * reduces exocrine pancreatic secretions * metastatic at time of diagnosis usually because these are so hard to diagnose

Question 29

Glucagonoma presentation?

Answer 29

* mild diabetes * characteristic rash → necrolytic migratiory erythema groin and LE * 4 D's: * Diabetes, Dermatitis, Depression, DVT

Question 30

VIPoma?

Answer 30

* Vasoactive intestinal peptide secreted by D1 cells * WDHA syndrome: * watery diarrhea * hypokalemia * achlorhydria * some patients have flushing * consider carcinoid syndrome in ddx