Diabetes Flashcards
What is diabetes insipidus?
deficiency of antidiuretic hormone
How many amino acids is insulin made up of?
51
What do the beta cells of Langerhans produce?
Insulin, glucagon and pancreatic polypeptides
What type of tissues can create a large carbohydrate reserve?
Skeletal muscle cells and fat cells
What cells do not require insulting for glucose uptake but are incapable of having large carbohydrate stores?
Neurons
What are the actions of insulin?
- uptake of glucose by cells
- uptake of amino acids by cells
- increased glycogen synthesis
- increased synthesis and esterification of fatty acids
- decreased lipolysis, proteinolysis and gluconeogenesis
How is insulin release mainly controlled?
Direct feedback
What are the acute consequences of insulin deficiency ?
- hyperglycaemia
- ketosis
- acidosis
- hyperosmolar state
What are the chronic consequences of insulin deficiency?
- cardiovascular disease
- nephropathy
- neuropathy
- retinopathy
What are the 4 types of diabetes?
Type 1
Type 2
Gestational
Secondary
What are the main elements of Type 1 diabetes?
autoimmune destruction of ß-cells
• probably triggered by viral infection
• Coxsackie or rubella viruses
• susceptibility partly dependent on HLA gene subtypes (HLA-DR3/DR4)
• classically starts in childhood, though adult onset not rare
What are the main elements of Type 2 diabetes?
pathophysiology complicated
• peripheral insulin resistance
• ß-cell response to glucose delayed or absent
• insulin concentrations normal or high
• strong association with lifestyle
• up to 20% prevalence in the elderly in the USA
What are the main aspects of gestational diabetes?
genetic predisposition
• insulin resistance, probably triggered by hormonal changes of pregnancy
• resolves with delivery
What are the risk factors for gestational diabetes?
maternal age • family history of DM type 2 • African or North American native • previous gestational diabetes • previous baby over 4Kg • smoking
What are the dangers for the mother with gestational diabetes?
mother • greater risk of DM type 2 later in life • hypertension • pre-eclampsia or eclampsia • obstructed labour
What are the dangers for the child in gestational diabetes?
child • risk of DM type 2 later in life • risk of obesity later in life • macrosomia • neonatal hypoglycaemia • neonatal jaundice • respiratory distress syndrome
What conditions cause secondary diabetes?
- chronic pancreatitis
- cystic fibrosis
- pancreatic surgery
- haemachromatosis
- endocrine disease
- eg Cushing’s syndrome
- drug therapy
- eg corticosteroids
What are the symptoms of type 1?
polyuria • polydipsia • hunger • weight loss • can be seen in DM type 2, but often camouflaged by other symptoms
How can diabetes mellitus present acutely?
ketoacidosis • rapid breakdown of fat and protein releases ketones (including acetone) and acids into bloodstream • hyperosmolar nonketotic state • severe dehydration • hypoglycaemia • diabetic foot
How does DM present chronically?
- Macrovascular
- ischaemic heart disease
- stroke
- peripheral vascular disease
- Microvascular
- retinopathy
- neuropathy
- nephropathy
- Cataract
What are the two routes of diabetic retinopathy?
- proliferation of blood vessels in the retina
- retinal haemorrhages
- macular oedema
- fluid exudation into retina
How does diabetic neuropathy present?
microangiopathy of vasa nervosum • peripheral numbness or tingling • occasional neuropathic pain • muscle weakness • autonomic neuropathy
How does diabetic nephropathy present?
- microangiopathy of glomerular capillaries
- pathology: nodular and diffuse glomerulosclerosis
- clinical: chronic renal failure or nephrotic syndrome; hypertension
What is diabetes mellitus?
- deficiency of insulin
* resistance to effects of insulin
