L14 - Diabetes

Question 1

Apart from CV disease what other long term diseases are diabetics at risk of?

Answer 1

• blindness (retinophathy)
• kidney disease (nephropathy)
• Neuropathy
• Diabetic foot
• amputation
• vascular disease
• heart attack
• intermittent claudication
• erectile dysfunction

Question 2

What are the typical SYMPTOMS of someone with currenlty untreated type 1 diabetes

Answer 2

polydipsia, polyphagia, polyuria, weight loss, blurring of vision, recurrent urogenital infections e.g. thrush, general malaise

Question 3

Clinically what are the criteria for diabetes?

Answer 3

1 abnormal test and symptoms or 2 abnormal tests

Tests are - Fasting glucose/non-fasting glucose/HbA1c

Question 4

Describe the management for a type 2 diabetic

Answer 4

weight loss, Lifestyle changes such as stopping smoking, exercise, low fat (specifically cholesterol diet), education, non-insulin medication such as metformin (gluconeogenesis inhibitor). Eventually insulin if required.

Question 5

What are the signs and symptoms of a DKA

Answer 5

Kussmaul breathing (Deep and laboured breathing), abdominal pain, nausea, vomiting, confusion and other symtpoms of untreated diabetes.
Signs are hyperkalaemia, a high anion gap and elevated ketones

Question 6

What is the treatment for a DKA?

Answer 6

fluids, insulin and electrolytes

Question 7

A type 2 diabetic presents as confused with extreme thirst. What complication could they possibly be undergoing

Answer 7

hyperosmolar non-ketotic syndrome

Question 8

What are some long term complications of untreated or poorly controlled diabetes

Answer 8

Kidney damage, blindness, foot ulcers, amputations, loss of sensation in fingers and toes, stroke, heart attack, excess sweating/passing gas.

Question 9

What is metabolic syndrome?

Answer 9

A clutser of the most dangerous risk factors associated with CV disease - diabetes, raised resting plasma glucose, abdominal obesity, high cholesterol and hypertension

Question 10

how many disulfide bonds are there in insulin?

Answer 10

3

Question 11

what is the half life of insulin?

Answer 11

5 minutes

Question 12

Which transporter allows glucose into pancreatic beta cells so the plasma glucose can be measured?

Answer 12

GLUT2 (this is also in the liver wheres GLUT4 is expressed on skeletal muscle and adipose tissue in repsonse to insulin

Question 13

What effect would an increase in ATP intracellular concentration have on a Beta cell?

Answer 13

would cause the closure of the ATP sensitive potassium channel -> depolarisation -> calcium moves in -> increase in release of insulin
NOTE - the ATP increase has come from the increased metabolism activity of glucose thus showing that there is an elevated amount of glucose in the plasma -> insulin needs to be released to signal cells to take it up

Question 14

what would you expect to happen to the concentration of C peptide in a diabetic who has just injected insulin?

Answer 14

remains the same - synthetic insulin is made without C peptide

Question 15

why can insulin only be injected and not taken orally?

Answer 15

insulin is a peptide hormone, if digested orally it would be broken down into its constituent amino acids thus rendering it inactive

Question 16

What is diabetic foot and how does it arise?

Answer 16

ulcers developing on foot because of a mixture of poor blood supply due to microvasculature damage and neuropathy

Question 17

what does aetiology mean?

Answer 17

The underlying cause of the disease

Question 18

What metabolism specific effects do glucagon and insulin have?

Answer 18

glucagon - stimulates glycogenolysis (lipogenesis and ketogenesis too) and gluconeogenesis in the liver
insulin - glycogenesis and translocation of GLUT 4 channels in liver, adipose and skeletal muscle

Question 19

Briefly explain the aetiology of type 1 diabetes

Answer 19

Autoimmune response where self tolerance to pancreatic beta cells is lost -> they are broken down by the body -> insulin can’t be produced -> glucose accumulates in the plasma

Question 20

Briefly explain the aetiology of type 2 diabetes

Answer 20

The body makes insulin but the glucose transporters are not sufficiently translocated in response to it i.e. the body’s cells develop an ‘insulin resistance’ - they don’t respond correctly to it.

Question 21

what are the risk factors for type 2 diabetes?

Answer 21

obesity/lack of exercise/hypertension/genetic factors

Question 22

explain why DKA doesn’t happen in type 2 diabetes generally

Answer 22

There is still circuating insulin -> the glucagon:insulin ratio isn’t sufficient to cause lipolysis

Question 23

What is hyperosmolar non-ketotic syndrome

Answer 23

Water moves into plasma because of it’s high osmolarity -> increased urination and massive dehydration -> can lead to mental status changes

Question 24

What are some tests and questions you would do on someone you believe is a newly presenting diabetic?

Answer 24

SQITARS
urine dip test to look at glucose and ketones
FBC
headaches?/weak?/thirsty or hungry?/frequency of urination?/fruity breath?