Diabetes Flashcards
What causes type 1 diabetes?
Progressive (assumed autoimmune) destruction of pancreatic beta cells, leading to complete deficiency in insulin production.
What are the classic triad of symptoms associated with type 1 diabetes?
Polyuria, thirst and weight loss.
What is the process that causes polyuria in patients with type 1 diabetes?
Glucose is usually reabsorbed in the proximal convoluted tubule of the kidney nephron, however, the elevated amount of glucose places a excessive load and so remains in the neprohon tube. This increases the osmotic load on the nephron, and less water is is reaboorsed to the blood stream causing the excretion of excessive amounts of urine.
What causes thirst in patients with type 1 diabetes?
Due to excess water loss in patients, as well as the osmotic affects of extra glucose in the blood stream in the osmotic centres of the brain.
What causes type 2 diabetes?
Characterised by slow progressive loss of Beta cells as well as increased resistance to insulin within the blood stream, generally in older (obese) patients.
What is the process of developing ketoacidosis in diabetic patients?
Decreease intake of glucose into cells due to the lack of insulin causes an increase in gluconeogenesis in the liver, which produces ketones. An increase presence of ketones in the blood stream lowers the pH and can lead to ketoacidosis.
What symptoms will often be present in those experiencing type 2 diabetes?
May present with the triad, however more likely to present with persistent tiredness, slow healing skin wounds, visual problems, persistent infections.
What are the possible macrovascular complications of diabetes?
Increases risk of stroke, increased risk of myocardial infarction, poor circulation to the periphery, especially feet.
Name some of the microvascular complications of diabetes?
Diabetic kidney disease (nephropathy), diabetic neurophathy (nerve damage), dieabetic eye disease (retinopathy), diabetic feet.
How does diabetic retinopathy affect the eyes?
Changes due to osmotic affects, (glucoma or possibly cataracts), as well as damaged blood vessels, which may leak and form protein excludes , and new blood vessels may form (proliferative retinopathy) which are weak and easily bleed.
How does diabetic foot develop?
Caused by the poor blood supply to the feet and damage to nerves (neuropathy).
What are the common treatments for type 2 diabetes?
Diet management, regular exercise, oral hypoglycaemic drugs, such sulphoureas which increase insulin release from blood cells and metaforim which reduces gluconeogensis.
What is the definition of diabetes?
A group of metabolic disorders characterised by chronic hyperglycaemia.
How can increased glucose concentrations cause damage to cells?
In cells such as nerves, eye and kidneys glucose is up taken based on the extracellular glucose concentration, in hyperglycaemia glucose is metabolised by aldose reductase, using NADpH to produce produce sorbitol which depletes the cell of NADPH leading to inapprioate disulphide bond formation.
What is the clinical significance of non-enzymatic glycoslation of proteins?
Glycosolated haemoglobin, as glucose reacts with the terminal valine of haemoglobin and the percentage glycosolated is a good indication of how effective blood glucose control has been. Red blood cells spend about 3 months in circulation so % HbA1c gives an indication of glucose concentration over the last 3 months, healthy individuals 4-6% in diabetic individuals potentially more than 10%.
