Metabolism S1 - Nutrition, Diet & Body Weight Flashcards
Which is the most common form of diabetes in the young?
Type I
What is Type I diabetes characterised by?
- Progressive loss and destruction of all or most of the β-cells
- Autoimmune
- Fatal if not treated immediately
What is Type II diabetes characterised by?
- Slow, progressive loss of β-cells but with disorders of insulin secretion and tissue resistance to insulin
- May not initially need treatment with insulin but all do eventually
The classic presentation of a Type I diabetic is a lean young person with history of a viral infection who present a Triad of symptoms - what are these?
1) Polyuria - Excess urine production. High levels of glucose in urine increases osmotic load on the nephron and less water is reabsorbed
2) Polydipsia - Thirst due to increased water loss + osmotic effects of glucose on the thirst centres
3) Weight loss - fat and protein are metabolised by tissue because insulin is absent
What genetic markers are considered genetic markers for Type I diabetes?
HLA DR3
HLA DR4
If high blood glucose levels in a type I diabetic is not treated, what is the outcome?
Diabetic ketoacidosis - life-threatening crisis
What symptoms do Type II diabetics present?
Classic triad of symptoms and:
- Lack of energy
- Persistent infection, especially thrush infections of the genitalia or infections of the feet
- Slow healing of minor skin damage
- Visual problems
Diabetics suffer from a number of macrovascular complications, particularly when blood glucose levels are poorly managed, what are they?
- Increased risk of stroke
- Increased risk of myocardial infarction
- Poor circulation to the periphery, particularly the feet
Diabetics suffer from a number of microvascular complications, particularly when blood glucose levels are poorly managed, what are they?
- Diabetic Eye disease (Glaucoma, cataracts and most important problem, diabetic retinopathy)
- Nephropathy (diabetic kidney disease)
- Diabetic Neuropathy
- Diabetic Feet
Explain Diabetic eye disease
- Osmotic effects of elevated glucose levels can lead to glaucoma and possibly cataracts
- Diabetic retinopathy
- Damage to blood vessels in the retina that leak and form protein exudates or rupture and cause bleeding in the eye
- New, weak blood vessels may form (proliferative retinopathy) which are prone to bleeding
Explain diabetic kidney disease
The kidney is affected by:
- Damage to the glomeruli or Poor blood supply because of changes in blood supply
- Damage from infections or the urinary tract which is more common in diabetics
What is an early sign of nephropathy?
Increased amount of protein in the urine - microalbuminuria
Explain neuropathy
High glucose levels damage nerve fibres, particularly in the legs and feet thought to be caused by microvascular damage to vessels that supply these nerves
Explain diabetic feet
Poor blood supply, damage to nerves, and increased risk of infection all conspire to make the feet of a diabetic particularly vulnerable. In the past, loss of feet through gangrene was not uncommon.
Living cells require energy for:
- Biosynthetic work
- synthesis of cellular components
- Transport work across cell membranes
- maintenance of ion gradients, uptake of nutrients
- Mechanical work
- Muscle contraction
- Osmotic work
- Kidney
What type of energy is used to drive the energy-requiring action of the body?
Chemical-bond energy