Diabetes Flashcards
Why wouldn’t you measure a diabetics blood insulin levels if you wanted to know how much they’re producing?
Because they are taking exogenous insulin so would give an inaccurate result
What are the three main presenting complaints with diabetes
Polyuria
Polydipsia
Weight loss
What tests would you run to diagnose diabetes?
What would their abnormal readings be?
Random venous glucose- >11.1mmol/L
Fasting venous glucose- >7.0mmol/L
HbA1C- >6.5%
List some other symptoms of diabetes
Fatigue
Blurry vision
Thrush (urogenital infections)
Weakness
In brief, what causes type I diabetes?
Insulin deficiency
In brief, what causes type II diabetes?
Insulin resistance
Describe some differences between Type I and II DM.
I- younger onset, rapidly fatal if untreated, need insulin
II- overweight, older people, may be asymptomatic for a long time, can reverse/reduce with diet and exercise
Could you use HbA1C for every case of suspected diabetes? Why?
No, not useful for those with sickle cell etc because the Hb won’t be present in the blood for long enough to become glycosylated
Why may somebody with diabetes suffer from recurrent urogenital infections (eg thrush)?
High levels of glucose in blood
Exceeds renal threshold
Glucosuria
Candida bacteria then have source of energy to thrive
Why does the body turn to producing ketones?
To try and preserve a source of energy for the brain to continue functioning.
How are ketone bodies produced?
When all other sources of glucose have been used up, B oxidation of free fatty acids occurs, forming Acetyl CoA. These are converted to HMG-CoA
HMG-CoA–>acetone + acetoacetate
Acetoacetate–> B-hydroxybutyrate
What causes ketoacidosis?
High levels of ketone bodies produced
These are acids and so when they release H+, lower blood pH
What signs/symptoms does ketoacidosis cause?
Nausea Vomiting Altered mental state Acetone breath Cardiac arrhythmia
What would an abnormal reading for random venous blood glucose test be? What would the normal ranges be?
> 11.1mmol/L
3.3-6mmol/L
What is the normal range for venous blood glucose?
3.3-6mmol/L
Why is weight loss a symptom of diabetes? (Lipid aspect)
Insulin usually inhibits lipolysis
TF deficiency would mean it’s no longer inhibited
Lipolysis (adipose TAG’s broken down to release glycerol and free FA into blood)
Why is weight loss a symptom of diabetes? (Muscle aspect)
Insulin deficiency no longer inhibits proteolysis
TF proteins are broken down to release AA’s into blood
What causes polyuria?
Hyperglycaemia Not all glucose is reabsorbed back into blood Osmotic gradient altered Less water reabsorbed Therefore lots of very dilute urine
What would an abnormal reading for random venous blood glucose test be?
> 11.1mmol/L
Describe the stages of treatment for Type II DM.
1st- Lifestyle diet changes (low calorie, no smoking etc)
2nd- oral hypoglycaemics-
Most commonly Metformin
Eventually- insulin
List and describe two acute complications of DM
Ketoacidosis
eventually coma
List macrovascular chronic complications of DM
Increased risk of MI, stroke, coronary artery disease
Peripheral vascular disease (gangrene etc)
List and describe some macrovascular complications of chronic DM
Diabetic kidney disease (damage to glomeruli and BV due to persistent infections, poor blood supply due to damage TF failure)
Diabetic eye disease (osmotic changes (glaucoma), retinopathy (IE BV damage + pop))
Erectile dysfunction
List two folgerkrankungen of persistent hyperglycaemia
Glycation of plasma proteins (TF lowers function) NADPH depletion (Aldose reductase action increased)
How does Metformin work?
What is it used for?
Type II DM
Slows uptake of GI glucose
Lowers liver gluconeogenesis
Increases glucose uptake by tissues
How does a low calorie diet aid DM recovery?
Decreases insulin resistance
What is the main cause of gestational diabetes?
B cell dysfunction meaning less insulin is produced
What are the risks to the mother with gestational diabetes?
Pre-eclampsia (raised BP, proteinuria)
What are the risks to the foetus in gestational diabetes?
Congenital malformation are 4x higher
Increased risk of miscarriage
Fetal macro soma (big shoulders- get stuck….
Shoulder dystocia
In pregnancy, which hormones act anti-insulin?
Cortictropin releasing hormone
Progesterone
Human placental lactogen
What effect do oestrogen and progesterone have with regards to insulin?
Increase sensitivity of B cells to glucose levels
List some macrovascular complications associated with DM
Retinopathy
Nephropathy
Neuropathy
