Diabetes Mellitus

Question 1

What is diabetes mellitus?

Answer 1

Deficiency of insulin

Resistance to effects of insuling

Question 2

What is insulin?

Answer 2

Peptide hormone with 51 amino acids produced in b cells of the islets of lagerhands of pancreas

Question 3

What does insulin do?

Answer 3

Regulate glucose uptake and metabolism

Question 4

What cells require insulin to absorb glucose?

Answer 4

Skeletal muscle cells and fat cells

Question 5

What cells do not require insulin to absorb glucose?

Answer 5

Neurons

Question 6

What are the actions of insulin?

Answer 6

Uptake of glucose
Uptake of amino acids
Increased glycogen synthesis
Increased synthesis and esterification of fatty acids
Decreased lipolysis, proteinlysis and gluconeogenesis

Question 7

How is insulin release controlled?

Answer 7

Mainly direct feedback with some autonomic control

Question 8

How is insulin released?

Answer 8

B cells absorb glucose via glucose transporter GLUT2
Metabolic pathway releases pre-synthesised insulin
Released by cholecystokinin derived from enteroendocrine cell intestinal mucosa

Question 9

What are the 4 acute consequences of insulin deficiency?

Answer 9

Hyperglycaemia
Ketosis
Acidosis
Hyperosmolar state

Question 10

What are the 4 chronic consequences of insulin deficiency?

Answer 10

Cardiovascular disease
Nephropathy
Neuropathy
Retinopathy

Question 11

What is T1DM?

Answer 11

Autoimmune destruction of b cells probably triggered by viral infection (coxsackie or rubella)

Question 12

What is the pathophysiology of T2DM

Answer 12

Peripheral insulin resistance
B cell response to glucose delayed/absent
Insulin conc normal/high

Question 13

What are the risk factors of gestational diabetes?

Answer 13

Maternal age
Family history of T2DM
African/north american
Previous GDM
Previous baby over 4kg
Smoking

Question 14

What are the dangers of gestational diabetes for the mother?

Answer 14

Increased risk of T2DM
Hypertension
Pre eclampsia
Obstructed labour

Question 15

What are the dangers of gestational diabetes for the child?

Answer 15

Risk of T2DM
Risk of obesity
Macrosomia (big baby)
Neonatal hypoglycaemia
Neonatal jaundice
Respiratory distress

Question 16

What are the causes of secondary diabetes?

Answer 16

Chronic pancreatitis
CF
Pancreatic surgery
Haemachromatosis
Endocrine disease
Drug therapy

Question 17

What are the symptoms of T1DM?

Answer 17

Polyuria
Polydipsia (thirst)
Hunger
Weight loss

Question 18

What is the threshold for glucose reabsorption?

Answer 18

Approx 10mmol/l

Question 19

What does glycosuria lead to?

Answer 19

Osmotic polyuria

Question 20

What does polyuria lead to?

Answer 20

Polydispia

Question 21

In the criteria for a diagnosis of diabetes, what does the fasting plasma glucose level need to be?

Answer 21

7.0mmol/l or above

Question 22

In the criteria for a diagnosis of diabetes, what does the random plasma glucose level need to be?

Answer 22

11.1mmol/l or above

Question 23

What are the 4 acute presentations of diabetes?

Answer 23

Ketoacidosis
Hyperosmolar nonketotic state
Hypoglycaemia
Diabetic foot

Question 24

What are the 3 chronic presentations of diabetes?

Answer 24

Macrovascular
Microvascular
Cataract