Diabetes

Question 1

What is insulinoma?

Answer 1

Insulin producing tumour in pancreas

causes hypoglycaemia

Question 2

What are the main causes of hypoglycaemia?

Answer 2

Insulinoma
Hypoadrenalism
Alcohol
Severe liver failure
Insulin or suphonylureas (Gliclazides)

Question 3

Insulin is secreted by what cells in the pancreas?

Answer 3

Beta cells

Question 4

Glucogon is secreted by what cells in the pancreas?

Answer 4

Alpha cells

Question 5

Where does glucose homeostasis predominantly occur?

Answer 5

Liver

Question 6

What is glucose stored as in the liver?

Answer 6

Glycogen

Question 7

When is glucose stored and released in the liver?

Answer 7

Stored during absorptive state

Released post absorptive state (Between meals)

Question 8

What does insulin suppress?

Answer 8

Gluconeogenesis and facilitated uptake of glucose for storage as glycogen

Question 9

What is the ratio of insulin and glucagon in the fed state?

Answer 9

High insulin

Low glucagon

Question 10

What is the ratio of insulin and glucagon in the fasting state?

Answer 10

Insulin low

Glucagon high

Question 11

How does insulin decrease blood glucose?

Answer 11

Increases glucose absorption into cells and out of plasma

Question 12

How does glucagon raise blood glucose?

Answer 12

Increases breakdown of glycogen to glucose in liver and upregulating gluconeogenesis

Question 13

What percentage of patients are type 1 diabetics?

Answer 13

10%

Question 14

What type of hypersensitivity reaction is type 1 diabetes?

Answer 14

Type 4 - one’s own T cells attacks beta cells of pancreas

Question 15

What genes have been identified in some Type 1 diabetics?

Answer 15

HLA DR3 and DR4 on Chr 6

Question 16

Type 1 DM symptoms

Answer 16

Glycosuria (glucose in urine)
Polyuria (increased urine)
Polydipsia (thirst)
Weight loss 
Polyphagia (hunger)

Question 17

Why do type 1 diabetics present with weight loss?

Answer 17

Lipolysis and breaking down of protein as adipose tissue and muscle try to produce their own energy

Question 18

Why does DKA occur?

Answer 18

Lipolysis causes fatty acids to be broken down into acetic acid and beta hydroxybutyric acid in liver.
These ketone bodies are acids and cause metabolic acidosis.
Body compensates - Kussmaul’s breathing
Acidosis and low insulin causes hyperkalaemia

Question 19

How does DKA cause hyperkalaemia?

Answer 19

Insulin normally stimulates Na+/Ka+ ATPase which enables K+ to enter cells.
Acidosis and large concentration of H+ outside the cell drive H+ into cell, therefore driving K+ out of cell.

Question 20

Percentage of T2DM in population

Answer 20

90%

Question 21

What happens to beta cells in T2DM?

Answer 21

Over time higher than normal insulin levels cause beta cell hyperplasia to try and normalise glucose levels
Amylin produced which builds up in beta cells causing damage and insulin then falls

Question 22

Can T2DM develop DKA?

Answer 22

No - they have normal insulin levels

Question 23

What is HHS?

Answer 23

Hyperosmolar Hyperglycaemia State
High glucose leads to extreme hyperosmolarity and dehydration causing cells to shrivel
Get mild acidosis

Question 24

Ways to diagnosis diabetes?

Answer 24

Random blood glucose
High fasting glucose
Oral glucose tolerance test (2 hours after glucose load)
HBA1C

Question 25

What is HbA1C?

Answer 25

Proportion of Hb in RBC which has glucose attached to it

Question 26

Long term consequences of diabetes?

Answer 26

Damage to microvasculature (Retinopathy, nephropathy)
Atherosclerosis
Neuropathy
Leg ulcers