Diabetes Flashcards
whats diabetes mellitus
group of metabolic disorderes characterised by chronic hyperglycaemia
due to insulin deficeny, insulin resistance or both
types of diabetes
their epidemiology
probable causation
treatment
TYPE 1
- young people
- characterised by progressive loss of all / almost all B cells
- rapidly fatal if not treated
- must be treated with insulin
TYPE 2
- usually older individuals
- characterised by the slow progressive loss of B cells along with disorders of insulin secretion ad tissue resistance to B cells
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can be present for long time before diagnosis
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lifestyle changes, drugs
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lifestyle changes, drugs
complications of diabetes
-CVD - Kidney disease - amputations
why does bgl ^
- inability to produce d to beta cell failure - insulin adequate B resistance / not working very well
type 1 how many people diagnosed annually?
what age group ^ common?
what causes it?
is there a genetic predispositon
15/100,000
younger people
autoimmune condiion where the body cant recognise self antigens from foreign antigens wc leads to the destrution of beta cells
there is, it is associated with genetic markers HLA DR3 and HLA DR4
there’s seasonal variationthough wc suggests a link viral infection acting asa trigger to rapid deterioration
how does a person with type 1 diabetes present
usually young with a triad of symtpoms:
polyuria - excess urine production. in the nephron of healthy individual all glucose filtered from the blood reabsorded, at the end of proximal convuluted tubule, resaborption is isosmotic. in diabetes mellitus large quantities of glucose is filtered by the kidney because bgl levels are high, so not all glucose reabsordbed. this extra glucose in the nephron tubule puts extra somotic pressure on the nephron so less water is resabsorbed to maintain the isoosmotic character of this section of the nephron. this extra water then reians with the glucose in the nephron tubule and is excreted in copius urine
weightloss - because fat an protein tissue is being metabolised because insulin is absent
thirst - due to water loss polydipsia
type 2
- not enough insulin - B deficiency relative , problem isn’t the beta cella but the target tissues wc have v sensitivity for insulin and so cant c glucose movement into liver,adopise, skeletal via GLUT4 -‘insulin resistance’
how does diabetes present?
- renal threshold related c excretion of urine and since glucose is osmoticallyaactive water s lost too; - polyuria, polydipsia , dehydration, blurred vision, urogenital infections (since bacteria like glucose, so ^ susceptible to thrush) -tiredness, fatugw, lethargy,weightloss -severitydeodning on the rate of bgl
how diagnosed type 1
- measuring plasma glucose levels wc is elevated d less insulin
- glucose in the urine ; glucosuria/glycosuria
- high ketones in the blood
how to diagnose type 2 diabetes
presence of symptom (polyuria/polydipsia/unexplained weightloss)
- random venous plasma glucose conc >11.1mmol/L or
- fasting plasma conc >7mmol/L or
- plasma glucose conc >11.1mmol/L 2 hours after andhydroud glucose adminstrered in oral glucose tolerance test OGTT
why do patients with type 1 present with diabetic ketoacidosis
due to less insulin you have a higher glucagon to insulin ration and so lyase HMG is activated + this paired with the high rate of beta oxidation favours the metabolism (of acetylCoA) and synthesis of ketone bodies e.g acetoacetate,acetone, and beta-hydroxybutyrate
acetone is breathed out and can be smelt on the breathe
due to these ketones bodies being produced they make the blood more acidic , metabolic acidosis occurs
patients prestn with hyperventilation, nausae, dehydration, stomach pain adn vomitting
test ketones in the pee
treatment
- replace hormone that’s lacking, insulin TYPE 1 always no tablet , just subcutaneous
what causes insulin resistance to develop
- physical inactivity -genetic influence -muscle na liver fat deposition -physical inactivity -central obesity
treatment for t2
- diet
- excersise
- pramalintide ( contains amylin wc c glucagon suppression form beta cells and slows down stomach emptying)
- biguanides METFORMIN wc v livers resistance to insulin so can take it up,
weightloss surgery (bariatric surgery)
acute complications
-diabetic ketoacidosis in t1 -hyperosmolar non-ketotic syndrome in type 2 (D waterloss you get ionic imbalance) -acure complication of hypoglycaemia IF TAKE TOO MUCH INSULIN WC IS HIGHEST CAUSE OF HYPOGLYCAEMIA ; coma since brain needs it