What is diabetes? Flashcards
what are the levels of BG and HbA1c that are diagnostic of diabetes?
fasting BG 6.1 - 7mmol/mol
random BG > 11.1 mmol/mol
HbA1c > 48mmol/mol
what is the presentation of type 1 diabetes?
symptoms i.e.
- polyuria
- polydypsia
- weight loss
- fatigue / tiredness
- blurred vision
- low grade infections i.e. thrush/balanitis
what is the presentation of someone with type 2 diabetes?
may have no symptoms
may have symptoms such as polyruia, polydypsia, blurred vision, low grade infections
wont have ketones in their urine
what is the diagnostic criteria for diabetes?
one test (BG or HbA1c) with symptoms or two tests (BG or HbA1c) without symptoms (you do the same test twice to make sure the results are concordant)
what does the HbA1c test measure?
HbA1c is glycosylated haemoglobin
it gives an indication of the blood glucose in the past 8-12 weeks
when can HbA1c not be used for diagnosis?
during pregnancy on drugs which raise BG i.e. steroids, anti psychotics renal failure acute pancreatic damage/surgery HIV allc hildren & young peoles patients who are currently ill short duration of symptoms
what is the diagnostic range of diabetes using the HbA1c test?
> 48 mmol/mol
however a HbA1c < 48 doesnt exclude diabetes
what tests can be carried out to diagnose diabetes?
fasting BG
random BG
OGTT ( measure BG 2 hrs after 75g carbohydrate - if > 11.1 mmol/l )
HbA1c
what factors may contribute to beta cell damage in type 1 diabetes?
genetic pre-disposition
environmental - trigger i.e. viral infection
autoimmune
what are the signs on examination of a patient who presents wit type 1 diabetes who has hyperglycemia?
ketones in the breath dehydration tachycardia hypotension low grade infections
what are the signs on examination of someone with type 2 diabetes?
not ketogenic
usually overweight
low grade infections i.e. thrush/balanitis
may have macro / microvascular complications at diagnosis
what is the criteria when someone would be screened for diabetes?
overweight FH over 30 if asian / Maori over 40 if european previous history of diabetes in pregnancy had a big baby ( >4kg) inactive life style previous high BG / impaired glucose tolerence
what is MODY?
mature onset diabetes in the young
what are the 2 mutations that cause MODY?
glucokinase mutations
transcription factor mutations
what are the differences between the glucokinase mutations and transcription factor mutations in MODY?
glucokinase - onset is young but TFM onset is adolescence & young adult
GK stab;e hyperglcaemia but TFM is progressive
treatment for GM is diet but 1/3 diet, 1/3 OHA and 1/3 insulin in TFM
complications are also rare in GM but frequent in TFM
