Lecture 14 Diabetes Mellitus

Question 1

What are the two types of diabetes mellitus?

Answer 1

Deficiency of insulin & insulin resistance

Question 2

Define diabetes inspidus

Answer 2

deficiency of antidiuretic hormone

Question 3

Where are peptide hormones produced?

Answer 3

Beta cells of islets of langerhans (pancreas)

Question 4

Where does glucagon bind to?

Answer 4

Cell membrane receptors

Question 5

What requires insulin to absorb glucose?

Answer 5

skeletal muscle cells and fat cells

Question 6

What do not require insulin to absorb glucose?

Answer 6

Neurons

Question 7

What does insulin do?

Answer 7

Makes cell uptake glucose and amino acids. ^glycogen and fatty acid synthesis. Decreases lipolysis, proteinolysis and gluconeogenesis.

Question 8

Where is insulin released from?

Answer 8

B-cells

Question 9

How is insulin release controlled?

Answer 9

direct feedback. Some autonomic control and CCK releases it. B-cells absorb glucose via glucose transporter GLUT2.

Question 10

What are the acute consequences of insulin deficiency?

Answer 10

Hyperglycaemia, ketosis, acidosis, hyperosmolar state.

Question 11

What are the chronic consequences of insulin deficiency?

Answer 11

CV disease, nephropathy, neuropathy, retinopathy

Question 12

What is type 1 diabetes mellitus?

Answer 12

Autoimmune destruction of B-cells

Question 13

What can trigger Type 1?

Answer 13

Viral infections (coxsackie or rubella viruses). Gene (HLA) subtype suseptibility. Childhood.

Question 14

Symptoms of type 1?

Answer 14

Polyuria, polydipsia, hunger, weight loss.

Question 15

Where (in normal glomerulus filtration) is glucose resorbed?

Answer 15

proximal renal tubule

Question 16

What is the threshold for resorption of glucose for glomerulus?

Answer 16

10mmol/l

Question 17

Polyuria->

Answer 17

glycosuria -> osmotic polyuria

Question 18

Define polydipsia

Answer 18

Very thirsty

Question 19

How is someone biochemically diagnosed with DM?

Answer 19

Fasting plasma glucose at or above 7.0mmol/l. 11.1mmol/l two hrs after 75g glucose of random test 11.1

Question 20

What are the acute presentations of diabetes mellitus?

Answer 20

Ketoacidosis, hyperosmolar nonketotic stat, hypoglycaemia, diabetic foot

Question 21

What is ketoacidosis?

Answer 21

Rapid break down of fat and protein releasing ketones and acid into blood. In DM type 1

Question 22

What is hyperosmolar nonketotic state?

Answer 22

Severe dehydration in DM type 2

Question 23

What are the chronic presentations of DM?

Answer 23

Macrovascular and Microvascular diseases

Question 24

What is retinopathy?

Answer 24

Proliferation of blood vessels in retina, retinal haemorrhages.

Question 25

Examples of macrovascular diseases?

Answer 25

Ischaemic heart disease, stroke, peripheral vascular disease. (effect coronary arteries, aorta, brain and limb arteries)

Question 26

Examples of microvascular diseases?

Answer 26

Retinopathy, diabetic neuropathy, nephropathy

Question 27

Notes on neuropathy?

Answer 27

Microangiopathy of vasa nervosum -> peripheral numbness/tingling, neuropathyic pain, weakness.

Question 28

Effects of autonomic neuropathy

Answer 28

Vomiting, diarrhoea, constipation, impotence, incontinence, anorgasmia, postural hypotension

Question 29

Define vasa nervosum

Answer 29

Small arteries that provide blood supply to peripheral nerves

Question 30

How can someone gain nephropthy?

Answer 30

Microangiopathy of glomerular capillaries.

Question 31

Pathology of nephropathy?

Answer 31

Nodular and diffuse glomerulosclerosis

Question 32

Clinical effects of nephropathy?

Answer 32

Chronic renal failure (nephrotic syndrome); hypertension

Question 33

What is type 2 DM?

Answer 33

Noninsulin dependent, Peripheral insulin resistance, B-cell response to glucose delayed or absent.

Question 34

What is gestational DM?

Answer 34

diabetes triggered by pregnancy (hormonal changes)

Question 35

What are the risk factors for gestational diabetes?

Answer 35

Maternal age, fam history of type 2, African/North American, previous babe over 4Kg. Smoking.

Question 36

What are the dangers to mother of gastational diabetes?

Answer 36

^ risk of DM type 2 later in life, hypertension, pre-eclamsia/clampsia (one of more convulsions. Obstructed labour.

Question 37

Dangers of gastational diabetes for child?

Answer 37

Risk of DM type 2 later in life, obesity, macrosomia, neonatal hypoglycaemia, jaundice, respiratory distress syndrome.

Question 38

What is macrosomia?

Answer 38

Excessive child growth in uterus

Question 39

What are the causes for secondary DM?

Answer 39

Chronic pancreatitis, CF, pancreatic surgery, endocrine disease (cushing's syndrome), Corticosteroids.

Question 40

What is haemachromatosis?

Answer 40

Hereditary disorder where iron salts are deposited in tissue -> liver damage/DM

Question 41

Infections more likely with DM. Give top two examples

Answer 41

Osteomyelitis (inflam of bone or bone marrow) and septicaemia.