Diabetes Flashcards
What’s the basic definition of diabetes mellitus?
- Deficiency of insulin
- Resistance to effects of insulin
True or false?
Insulin is an Amine hormone?
FALSE!
It’s a peptide hormone. Produced in the B-cells of the islet of the pancreas.
What is the role of insulin?
- It regulates glucose uptake and metabolism
- Has a role in uptake of amino acids
- Causes increased glucogen synthesis
- Increases synthesis and esterification of fatty acids
- Causes decreased lipolysis, proteinolysis and gluconeogenesis.
Do neurons require insulin to absorb glucose?
No, they cannot accumulate significant carbohydrate reserves so do not require insulin.
Do skeletal muscle cells and fat cells require insulin to absorb glucose?
YES. Both can accumulate large carbohydrate reserves.
How is insulin release controlled?
- Mainly by direct feedback (B-cells absorb glucose via glucose transporter GLUT2)
- Some autonomic control
- Also released by Cholecystokinin derived from entero-endocrine cells of intestinal mucosa.
What are some of the ACUTE consequences of insulin deficiency?
- HYPERglycemia
- Ketosis
- Acidosis
- Hyperosmolar state (dehidration)
What are some of the CHRONIC consequences of insulin deficiency?
- Cardiovascular disease
- Nephropathy
- Neuropathy
- Retinopathy
Name some types of diabetes?
- Type1
- Type2
- Gestational
- Secondary
Characteristics of Type 1 diabetes???
- Autoimmune destruction of Bcells. probably triggered by viral infection (Coxsackie or rubella virus)
- Susceptibility partly relies on HLA gene subtype (HLA-DR3/DR4)
- Classically starts in childhood, though adult onset not rare.
Which type of diabetes typically starts in childhood?
Type 1. But adult onset is not rare.
What are some of the former names of Type 2 diabetes mellitus?
- Non insulin dependant diabetes mellitus (NIDDM)
- Obesity related diabetes mellitus
- Adult-onset diabetes mellitus
Characteristics of Type 2 diabetes mellitus?
- Pathophysiology complicated!
- Peripheral insulin resistance
- B-Cell response to glucose delayed or absent
- Insulin concentrations norma;/high
- STRONG association with lifestyle (obesity)
Characteristics of Gestational Diabetes?
- Genetic Predisposition
- Insulin resistance probably triggered by hormone changes of pregnancy
- Resolves with delivery
What factors pose a risk with gestational diabetes?
- Maternal age
- Family history of T2DM
- Africal/north american native
- Previous gestational diabetes
- Previous baby over 4kgs
- Smoking
There are some risks to the mother in gestational diabetes. Name some:
- Greater risk of T2DM later in life for the mother.
- Hypertension in mother
- Pre-eclampsia or eclampsia
- obstructed labour
There are some risks to the child in gestational diabetes. Name some:
- Risk of T2DM in later life
- Risk of obesity in later life
- Macrosomnia (big baby)
- Neonatal hypoglycaemia
- Neonatal jaundice
- Respiratory distress syndrome
What can cause secondary Diabetes Mellitus?
- Chronic pancreatitis
- Cystic fibrosis
- Pancreatic surgery
- Haemachromatosis (high iron levels)
- Endocrine disease (Cushing’s syndrome)
- Drug therapy (corticosteroids)
Hunger, Polyuria (large volume of urine), polydipsia (thirst), weight loss are all classic symptoms of what type of diabetes?
T1DM
Can be seen in T2DM but often camouflaged by other symptoms
What is polyuria?
It’s when high levels of urine. Glucose can be found in urine also (glucosuia).
Polyuria leads to polydipsia (high thirst)
What’s the biochemical diagnosis for diabetes mellitus?
Hint BM
- Fasting plasma glucose level at or above7.0mm
- 2 hours after 75g oral glucose load 11.1 or above
- Random plasma glucose at or above 11.1mm
What’s ketoacidosis?
It’s causes by the rapid breakdown of fats and proteins which releases Ketones (including acetone) and acid in bloodstream.
Usually type one, rarely T2DM. Can lead to coma and death.
What’s hyperosmolar nonketotic state?
It is sever dehydration and can lead to come and death. Usually T2DM
What’s hypoglycaemia?
It’s insulin overdose, generally accidental and can lead to come and death.
What are some of the risks of diabetic foot?
It can lead to sepsis, amputation, and death.
What’s macrovascular disease?
It’s a disease of any of the large blood vessles and can be a presentation of chronic diabetes. Can cause ischemic heart disease, stroke, and peripheral vascular disease.
What’s microvascular disease?
It’s disease of any small vessles of the body and can be a presentation of chronic diabetes. Can cause retinopathy, neuropathy and nephropathy.
What is diabetic Retinopathy?
It’s proliferation (increase in number) of vessels in the retina causing retinal haemorrhages. Can cause macular oedema (fluid exudate into retina) and blindness.
What is the name given to the diabetic condition that causes proliferation of blood vessles in the retina and can cause blindness?
Diabetic Retinopathy
What’s diabetic neuropathy?
It’s disease of the small blood vessels (microangiopathy) in the vasa nervosum. Causes: -peripheral numbness/tingling
- occasional neuropathic pain,
- muscle weakness
- autonomic neuropathy (vomiting, diarrhoea, constipation, impotence, incontinence, anorgasm, postural hypotension)
What’s diabetic nephropathy?
It's disease of the small blood vessles (microangiopathy) in the glomerular capillaries. Causes: -Chronic renal failure -Nephrotic syndrome -Hypertension
True or false:
Diabetic are at no higher risk of infections compared to non-diabetics?
FALSE
They are at increased risk of many infections such as- post op, spticaemia, rectal abscess, pyelonephritis, osteomylitis
