1)Diabetes Flashcards
Type 1 Aetiology
10% of people with diabetes have type 1
half of cases are due to mutations/ genes in HLA/MHC or insulin protein
also due to viruses, gut microbiome and vitamin D deficiency.
Type 2 Aetiology
90% of people with diabetes have type 2
Most cases are due to insulin resistance caused by obesity.
but also mutations/ genetics involving insulin secretion from Beta cells or glucose uptake.
Main risk factors of Type 2 diabetes
Obesity, genetics, diet, lack of physical activity.
Explain the term ‘insulin resistance’ and briefly state the main disease process involved in the development? (4)
Insulin resistance means the the insulin receptor signaling pathway is not working properly due to the glucose-transporter Glut 4 is not activated to move to the cells surface and glucose is not taken up from the blood. This can be caused by free fatty acids, caused by obesity, blocking the insulin signaling pathway.
Explain what happens in diabetic ketoacidosis
There is low insulin produced, usually in T1DM, so the glucose cannot enter cells because the insulin receptor is not stimulated. The body starts to break down fats as a source of energy. The by product of fat breakdown are ketones- which are acidic and can cause dangerous build up of acid.
Explain the cause of neuropathy (Damaged nerves)
Hyperglycemia is the main cause. Hyperglycemia damages endothelial cells in the fine blood capillaries, making them more stiff or leaky/permeable and reducing their supply of oxygen and nutrients. This leads to ischemia of the neurons. Hyperglycemia may also directly damage the neurons themselves , and the very long delicate neuronal axons that reach the extremities of the body which are susceptible to damage.
Explain the main cause of nephropathy
Hyperglycemia is the main cause. Hyperglycemia damages the endothelial cells in the fine blood capillaries in the glomerulus of the nephron; this makes them more stiff or leaky/ permeable. This damages their filtration ability allowing large proteins such as albumin to leak out into the filtrate leading to excess albumin in the urine.
Explain the cause of diabetic retinopathy
Hyperglycemia is the main cause. Hyperglycemia damages endothelial cells in the fine blood capillaries in the retina; this makes them more stiff or leaky/ permeable and blood leaks out into the retina and the new blood vessel networks start forming on the retina.
What are the main symptoms of diabetes?
Hyperglycemia: profound increase in blood glucose levels
Polyuria: (excessive normal passage of urine) caused by osmotic diuresis secondary to hyperglycemia.
Severe nocturnal enuresis (bedwetting): Normally in children
Excessive thirst: in response to hyperosmolar state (due to increase level of glucose in blood) & dehydration.
