diabetes

Question 1

what is the endocrine function of the pancreas?

Answer 1

the beta cells secrete insulin and the alpha cells secrete glucagon

Question 2

what does insulin do?

Answer 2

lowers blood glucose as its stimulated by high blood glucose

Question 3

what does glucagon do?

Answer 3

raises blood glucose stimulated by low blood glucose

Question 4

What hormone is released at hyperglycaemia?

Answer 4

Blood glucose concentration too high from set point so insulin released

Question 5

What hormones are released at hypoglycaemia?

Answer 5

Blood glucose comcentration is too low from set point so glucagon and adrenaline are released

Question 6

What chemical processes occur during hyperglycemia?

Answer 6

glycogenisis = the conversion of glucose to glycogen
- conversion of glucose to lipid
- increased metabolism so increased respiration to reduce blood glcuose levels

Question 7

What chemical processes occur during hypoglycaemia

Answer 7

glycogenolysis = breakdown of glycogen to glucose

Question 8

what is polydipsia?

Answer 8

thirst due to fluid loss and increased osmolarity

Question 9

what defines type 1 diabetes

Answer 9

absolute need for insulin therapyw

Question 10

what defines type 2 diabetes?

Answer 10

non insulin dependent diabetes and is the most common form of diabetes

Question 11

what is gestational diabetes?

Answer 11

diabetes that develops during pregnancy and usually disappears after giving birth

Question 12

what can diabetes be secondary to?

Answer 12

-pancreatic disease
-other endocrine disease e.g. cushings syndrome
-drugs
-abnormalities of insulin/ insulin receptor
-genetic syndromes - cystic fibrosis

Question 13

for type 1 diabetes (IDDM) what can cause it and how can it be treated?

Answer 13

caused by:
-genetic predisposition
-autoimmune destruction of beta cells
-environmental factors like viruses or chemicals
treated by:
-insulin injections and diet

Question 14

for type 2 diabetes (NIDDM) what can cause it and how can it be treated?

Answer 14

caused by
-multifactorial inheritance
-down regulation of insulin receptors so they have a reduced response to insulin
treated by
-dietary management and exercise
-oral hypoglycaemic agents

Question 15

what is the genetic susceptibility of type 1 diabetes associated with?

Answer 15

-HLA
-DR3
-DR4

Question 16

for type 1 diabetes, what lesions can it cause and what causes them

Answer 16

islet lesions - in early stages these cause inflammation and in later stages cause atrophy and fibrosis
caused by cell autoantibodies

Question 17

what happens as a result of hyperglycemia?

Answer 17

check screenshots

Question 18

what lesions are formed in type 2 diabetes?

Answer 18

tissue fibrosis and amyloid

Question 19

is there HLA association with type 2 diabetes?

Answer 19

no

Question 20

what do diabetic complications depend on?

Answer 20

-severity and duration of hyperglycaemia
-level of glycaemic control

Question 21

give 3 acute complications of diabetes type 1 what are the symptoms

Answer 21

hypoglycaemia symptoms
-shaking, sweating, tachycardia
-hunger
-headache
-sudden moodiness
-behaviour changes, confusion
-blurred vision

ketoacidosis (this is worse than the non-ketoic version) where there’s a severe lack of insulin in the body
-blurred vision
-thirsty
-stomach pain
-more frequent urination
-confusion
-tiredness

hyperosmolar non-ketoacidotic coma
-severe hyperglycaemia
-dehydration
-lethargy

Question 22

give the symptoms of diabetes in the following categories:
-central
-systemiic
-repiratory
-eyes
-breath
-gastric
-urinary

Answer 22

-polydipsia, polyphagia, lethargy and stupor
-weight loss
-hyperventilation
-blurred vision
-smell of acetone in the breath
-nausea, vomiting, abdominal pain
-polyuria, glycosuria

Question 23

give general complications in diabetes

Answer 23

-reduced immune and poor healing response
-hyperglycemia
-reduced immune cell function
-increased inflammation
-bacterial and fungal infections

Question 24

give chronic complications in diabetic macrovascular disease

Answer 24

-cardiovascular disease
-peripheral vascular disease
-diabetic foot

Question 25

give chronic complications in diabetic microvascular disease

Answer 25

-diabetic neurapathy
-diabetic nephropathy
-diabetic cardiomyopathy
-diabetic retinopathy

Question 26

what are the consequences of atherosclerotic lesions?

Answer 26

-cardiovascular disease
-vascular insufficiency causing brain infarction and gangrene/ ulcers in legs

Question 27

give two examples of diabetic foot

Answer 27

-ulceration
-gangrene due to ischaemia

Question 28

how can diabetes cause major vascular disease?

Answer 28

by causing atherosclerotic lesions where the blood vessel is blocked

Question 29

what does diabetic microvascular disease cause?

Answer 29

-increased thickness of capillary basement membrane
-arteriolosclerosis
-vascular occlusion
-defective healing in chronic ulcers
-major complications in kidney and retina
-nerve damage

Question 30

what is diabetic nephropathy? what does it cause?

Answer 30

a renal faliure that mainly occurs in IDDM over NIDDM
-necrotising papillitis
-diabetic glomerulosclerosis

Question 31

what is diabetic glomerulosclerosis?

Answer 31

an end stage renal disease causing chronic renal faliure due to the BM changing and renal hyperfusion

Question 32

what is diabetic neuropathy? what does it cause?

Answer 32

-thickened capillaries and ischaemia
it causes:
-glycosylated nerve proteins
-axonal degeneration
-loss of myelination causing reduced conduction velocity
-reduced sensation
-muscle weakness, atrophy, wastage
-ptosis which is the 3rd cranial nerve palsy

Question 33

give some common occular complications of diabtes

Answer 33

-cataracts
-background diabetic retinopathy
-serious diabetic retinopathy
-endstage diabetic retinopathy

Question 34

what are the stages in diabetic retinopathy?

Answer 34

1. microaneurysms
2. haemorrhages
3. exudates
4. proliferative DR

Question 35

what does background diabetic retinopathy look like

Answer 35

scattered microaneurysms and dot haemorrhages

Question 36

what does serious diabetic retinopathy look like?

Answer 36

-cotton wool spots
-hard exudates
-haemorrhages
-venule bleeding
-vessel breakage

Question 37

what does end stage diabetic retinopathy consist of?

Answer 37

-uncontrolled new vessel growth
-fibrous tissue contraction
-retinal traction
-retinal detachment
-visual loss

Question 38

How is the increase in blood glucose regulated?

Answer 38

1. Stimulus of the increased blood glucose concentration is detected as the input signal by the receptors being beta cells in the pancreas
2. The output signal triggers insulin release which is a polypeptide hormone so a chemical messenger
3. Effectors = liver/ muscle tissue
4. Insulin binds to the protein receptor in the cell surface membrane of liver / muscle cells.
5. Tertiary protein structure changes shape and the cells insert carrier proteins through which the glucose can enter the cell via facilitated diffusion
6. Glucose is polymerised into glycogen
7. Response is triggered of blood glucose concentration being lowered
8. Negative feedback

Question 39

How is a decrease in blood glucose concentration regulated?

Answer 39

1. Stimulus of the decreased blood glucose concentration is detected as the input signal by the receptors being alpha cells in the pancreas
2. The output signal triggers glucagon release which is a polypeptide hormone so a chemical messenger
3. Effectors = liver
4. Glucagon binds to the protein receptor in the cell surface membrane of liver cells.
5. Tertiary protein structure changes shape and the cells insert carrier proteins
6. Glycogen glycosidic bonds are hyrolysed to release alpha glucose which moves out if tge carrier proteins by facilitated diffusion
7. Response is triggered of blood glucose concentration being increased
8. Negative feedback

Question 40

What three factors influence blood glucose concentration?

Answer 40

• glucose from hydrolysis of consumed carbohydrates such as starch
• glycogenolysis
• gluconeogenisis

Question 41

give 2 oral hypoglycaemic agents

Answer 41

-sulfonylureas which stimulate insulin production
-metformin which inhibits liver glucose production

Question 42

what is necrobiosis lipoidica diabeticorum?

Answer 42

a skin condition mainly seen in women as a result of diabetes that causes severe ulceration

Question 43

what are the two types of diabetes mellitus?

Answer 43

-insulin dependent diabetes mellities - type 1
-non insulin dependent diabetes mellitus type 2

Question 44

what are the two mechanisms that are involved in the chronic complications of diabetes?

Answer 44

-polyol pathway: glucose is absorbed into tissue and converted into sorbitol
-protein glycosylation: releases advanced glycation end -products which inactivates protein and increases BM thickness

Question 45

why is cardiovascular disease a major cause of death in patients with diabetes?

Answer 45

due to accelerated atherosclerosis causing
-coronary artery disease
-ischaemic heart disease
-myocardial infarction

Question 46

why is wound healing compromised in diabetics?

Answer 46

-compromised immune cell function causing a decreased immune response
-compromised blood flow reduces o2 supply and reduced metabolites delays healing