Online module 1 Mrs Greene Flashcards
What saying is used to help remember the signs of hypercalcaemia ?
It can cause increased urination but not as much as in diabetes.
Think Groans (constipation), Moans (depression and fatigue), Bones (sore bones), and (kidney) Stones
When a patient has increased frequency of urination what additional symptoms would indicate a UTI?
If it was painful to pass urine or if it had a foul smell
Define what diabetes insipidus is
Diabetes insipidus can be caused by low or absent secretion of the water-balance hormone vasopressin from the pituitary gland of the brain, or by a poor kidneyresponse to this chemical messenger, which is also called antidiuretic hormone.
If you were worried about the patient having diabetes insipidus and needed to differentiate it from diabetes mellitus what could you do?
Fluid deprivation test in which fluid output would not decrease in a patient
What is specifically damaged in T1DM (hint in terms of the pancreas)?
Destruction of pancreatic beta cells
What is the purpose of urinanalysis in checking for diabetes ?
In a potential diabetic patient they may well have hyperglycaemia which means theres too much glucose in the blood and it leads to glucose being present in the urine which is detected in urinanalysis which calls for further tests to prove or disprove a diagnosis of diabetes
What random bloog glucose level would be indicative of diabetes ?
Blood glucose >11.1 mmol/L
This alone is not diagnostic, needs to have symptoms of diabetes also to diagnose with this, or 2 measurements on separate occasions over this limit would be diagnostic
HbA1c what is this mainly used for in diabetes ?
More commonly used in monitoring glucose control in known diabetics - hence monitoring effectiveness of there treatment. It can be useful in helping diagnose
HbA1c > 48mmol/L is indicative of diabetes
What does the detection of iselt autoantibodies point to?
T1DM rather than T2DM
What is gluconeogenesis ?
Gluconeogenesis is the metabolic process by which organisms produce sugars (namely glucose) for catabolic reactions from non-carbohydrate precursors.
e.g. amino acids to glucose
What is the ideal plasma concentration of glucose ?
3.6 to 5.8 mmol/L
How many different hormones regulate plasma glucose concentrationa and what is different about the action of insulin in this regulation compared to the rest?
5 different hormones - insulin is the only one which by its action decreases plasma glucose concentration
Where is insulin produced ?
In beta cells of the iselts of langerhans in the pancreas
What are the 4 different roles which insulin carries out to encourage storage of carbohydrate as a way of reducing blood glucose ?
- Facilitation of glucose transport into cells (through glucose transporter 4 (GLUT-4) recruitment in insulin-dependant tissues)
- Stimulation og glycogenesis (synthesis of glycogen from glucose)
- Inhibition og glycogenolysis (breakdown of glycogen into glucose)
- Inhibition of gluconeogenesis
Insulin has some addition effects where it works on fatty acids and amino acids - what are these effects ?
Fatty acid effects:
- Encourages entry of fatty acids into adipose tissues
- Promotes chemical reactions that use fatty acids (for triglyceride synthesis)
- Inhibits lypolysis
Amino acid effects:
- Promotes uptake of amino acids into muscles and other tissues
- Stimulates protein synthesis
- Inhibits degradation of protein
Through what mechanism is insulin secretion regulated ?
It is regulated by a feedback loop:
This means the release of insulin is controlled by its own action
- Presence of glucose in pancreatic beta cells stimulates insulin secretion
- Insulin takes affect and decreases blood glucose conc which results in less glucose entering the beta cells.
- This results in less insulin secreted
What are the other additional factors which regulate insulin secretion ?
- Food ingestion
- Blood amino acid levels
- Sympathetic and parasympathetic ANS
How does food ingestion also regulate insulin secretion ?
In the presence of food ingestion a number of GI hormones (most notibly - glucose dependant insulinotropic peptide) stimulate insulin release in a feed-forward way, this means insulin can be synthesised and secreted in anticipation of nutrients being absorbed.
How does blood amino acid levels also regulate insulin secretion?
Elevated blood amino acid levels stimulate insulin secretion as it then decreases amino acid levels (same sort of negative feedback loop as with insulin and blood glucose levels)
How does the sympathetic and parasympathetic ANS also regulate insulin secretion ?
Pancreas is stimulated by both:
Digestive tract is stimulated by parasympathetic nervous system when food is being digested this stimulation as exerts an effect on the pancreas stimulating insulin synthesis and secretion.
Stimulation of the pancreas by the sympathetic nervous system decreases insulin synthesis and secretion. This is cause when exercising (using sympathetics) blood glucose levels arent restricted by insulin at a time when needed.
What are the 4 hormones capable of increasing blood glucose levels ?
- Glucagon
- Adrenaline
- Cortisol
- Growth hormone
What is the function of glucagon and where is it produced ?
Produced in alpha cells in the iselts of langerhans.
Works to prevent hypoglycaemia converting glycogen into glucose. Stimulated by decreased blood glucose conc or increased amino acid levels in the blood.
Where is adrenaline produced and what is its function ?
Released from the adrenal glands (in reposne to sympathetic stimulation ‘‘fight or flight’’) - Its for emergency situations where it inhibits insulin secretion as well as increasing synthesis of glucose and stimulating the actions of glucagon.
What is the function of cortisol and when is it produced ?
It is produced in reponse to stress.
Increases blood glucose conc by inhibiting glucose uptake in the tissues. Also encourages the degradation of proteins.
What is the function of growth hormone and when is it produced ?
Stimulated in response to hypoglycaemia, stress, exercise and deep sleep.
It works to promote growth, doesnt usually play a major role in fuel metabolism. It decreases glucose uptake in the muscles and increases protein synthesis.
What are the main symptoms of DM ?
All on the pic - these are just some of the definitions of the words
polyphagia = excessive hunger/ increased appetite
stupor = state of near unconsciousness
kussmaul breathing = deep laboured breathing
Why do patients with diabetes lose weight ?
Because there is increased lipolysis
How does visual blurring occur in diabetes ?
High levels of glucose in the blood can be absorbed by the lens of the eye changing its shape causing the blurring, lens usually changes back to normal shape once normal glycaemic control is obtained
Why are diabetics more susceptible to infection ?
A number of reasons:
- Diabetes has a detrimental effect on the immune system.
- Delayed wound healing
- Increased hospital admissions
- Particularly prone to resp and urinary infections
- Female diabetics prone to thrush - due to impaired immune system and more acidic vaginal pH
What is kussmauls breathing a sign of and what type of diabetes is it associated with?
Associated with type 1 not type 2.
Occurs in the presence of excessive ketone bodies in the blood which can usually be smelled as acetone on a patients breath. It is a sign of DKA
What is the pathogenesis of T1DM?
The destruction of pancreatic beta cells - reason is unkown it however may be autoimmune in origin in some cases hence detection of iselt autoantibodies
What is given to treat T1DM and how is it given usually ?
Biosynthetic human insulin is given usually by either injections or insulin pump
What is the preferred insulin regime for T1DM?
Injected insulin:
Patient uses 2 different insulin types - a bolus of slow acting insulin injected usually at bedtime to act in the background, and a short acting insulin around 15 mins before a meal (this means they have to adjust dose as appropriate to amount of carb in a meal).
When are insulin pumps sometimes the best option in treatment for T1DM?
For patients struggling to achieve normoglycaemia with injected insulin
How does an insulin pump work ?
By delivering a continuous background dose of insulin and having the patient provide a boost to coincide with mealtimes
What healthcare workers are required to help when going on an insulin pump ?
Doctor, dietitian and specialist nurse
Diabetes in the mother can harm the baby during pregnancy (esp during first 8 weeks and if poor glycaemic control) - what are babies especially at risk of developing ?
CNS deformities - such as anencephaly, spina bifida, caudal regression and abnormalities of the great vessels
Babies of diabetic mothers are prone to having larger birth weights but not increased length, why?
This is because glucose can diffuse across the placenta but insulin cannot, and if the mother has poor glycaemic control during pregnancy then the baby will have increased fat, skeletal growth and organomegaly (therefore increased weight)
When born the baby will be producing much higher levels of insulin than it should be due to high levels from mum during pregnancy - this can result in hypoglycaemia soon after birth
Outline the genetic risks of diabetes
T1DM:
- 0.5% incidence in general population
- If you have siblings or parents with it risk is 5-6 %
- Dizygotic twins have risk of 5-10% if one has it
- monozygotic have 30-4% risk if one has it
T2DM:
- 5% incidence in general population
- If a first degree relative has it then 10-15% risk
- In monozygotic twins risk is 90% if one has it
Therefore much greater genetic risk for T2DM
What is the management of diabetes during pregnancy ?
There glycaemic control is advised to be optimised before getting pregnant.
For T2DM on metaformin its safe in pregnancy so if they have good glycaemic control then they continue using it, if poor control then go onto insulin during pregnancy.
Advised to take folic acid, and there is a higher risk of still births, pre-eclampsia and maternal death.
Diabetics have a reduced life-expectancy and the younger they were diagnosed the worse it is - T/F?
True
