Diabetes Mellitus Flashcards
What is diabetes mellitus?
lack of or decreased effectiveness of endogenous insulin –> diabetic hyperglycaemia
What causes T1DM?
there is autoimmune b-cell destruction –> no insulin signal –> diabetic hyperglycaemia
~ often occurs before puberty.
HLA-D3 & D4 gene linked!
What antibodies are made in LADA? aka latent autoimmune diabetes of adulthood
islet cell antibodies
[islet cells contain alpha, beta, delta and C-cells]
- is like a subset of T1DM tf as there is no insulin signal
What causes T2DM?
no response to insulin
there is resistance / b-cell dysfunction
~older patients
there is ketosis prone T2DM and MODY
What is MODY and its inheritance pattern?
Mature Onset Diabetes of the Young (MODY)
AD inheritance, e.g < 25 years
- genetic DEFECT of B-cell function –> dysregulation
(not destruction so tf = T2DM)
–> Increased risk of HCC (hepatic carcinoma)
What do these conditions cause:
steroids
pancreatic: surgery/trauma, infection, haemochomatosis, CF, cancer
endocrine - cushings, acromegaly, phaeochromocytoma, hyperthyroidism
congenital lipodystrophy, glycogen storage disease?
secondary diabetes!
specifically haemochomatosis –>bronze diabetes
CF –> mucus blocks pancreatic duct
Cushings -> as Increased glucocorticoid, hyperglycaemia = increased insulin –> tolerance
What is a non-diabetic hyperglycaemia?
GDM - gestational diabetes
What are the OGTT fasting glucose values to diagnose GDM?
OGTT =>
0 mins > 5.6 mmol/L
2 hr > 7.8 mmol/L
What do these represent: miscarriage preterm labour pre-eclampsia congenital malformations macrosomia worsening of diabetic complications e.g. retinopathy, nephropathy?
the increased risks
that all forms of DM
- T1 or T2 or GDM
bringto both the mother and foetus
What are the increased risks that all forms of DM bring to mother & foetus
to mum: - worsening of diabetic complications, retinopathy, nephropathy - pre-eclampsia to child: - miscarriage - preterm labour - congenital malformations - macrosomia
What are RFs for GDM?
> 25 y/o previous GDM Fhx inc BMI non-caucasian HIV +ve
What is recommended for those at risk of GDM or with DM before conception?
folic acid 5mg/daily until 12 weeks pregnant
weight loss
good glucose control, discuss risks
How do you screen for GDM?
1) OGTT
2) then 6 wks post partum = fasting glucose
[75g glucose @
0 mins > 5.6 mmol/L
2 hr > 7.8 mmol/L]
NB: 6 wks later – 50% go onto develop DM eventually
What hypoglycaemics can carry on in pregnancy?
all oral hypoglycaemics other than metformin should be discontinued
- metformin as an adjunct/alternative to insulin in T2 or GDM
What are the differences between T1DM and T2DM typically in: age body habitus onset symptoms diagnosis route/presentation genetic dispositon population?
T1DM are young, normal weight, onset over days w: moderate/severe symptoms; polydipsia, polyuria, weight loss, ketosis –> acute diagnosis. population = 5-10%
FOR both there is a genetic predisposition (more in T2DM even)
T2DM are old, overweight, weeks of onset, none or mild syx - or present with complications e.g. MI. diagnosed on routine check and = 90-95% of DM population.
A pregnant lady’s fasting glucose result is 5.6 mmol/L is this normal or DM or GDM?
it is normal as ≤ 6 is normal
but because she is pregnant it is boarderline GDM ( ≥ = 5.6)
Someones fasting glucose if 6.5 is this normal?
it is impaired
e.g. 6.1 - 6.9 = impaired
normal is ≤ = 6
DM = ≥7
Someones fasting glucose is 7.1, is this normal?
no, DM is ≥7
Someones random glucose is 10.0 mmol/L is this normal?
yes ≥ 11.1 = DM
cant do GDM off random glucose
Somones OGTT is 5.0 mmol/L is this normal?
yes as < 7.8
Someones OGTT is 10 is this normal?
no it is impaired
7.8 - 11 = impaired
A pregnant ladys OGTT is 7.9 is this normal
no it is not as
≥ 7.8 = GDM
NB: for OGTT it is the same for DM as GDM (>7.8)
Someones HBA1C is 43 mmol/mol is this normal?
no normal is < 42 mmol/mol
Someones HBA1C is 43 is this DM?
no it is impaired
e.g. 42 - 47 is impaired
Someones HBA1C is 50 mmol/mil is this DM?
yes
≥48 = DM (6.5%)
What is HBA1C?
glycosylated Hb
average blood glucose for 2 - 3 months
What doe these groups indicate?
ALL children & young people
-T1DM
- Symptoms < 2 months
- Acutely ill (i.e. hosp admission) + high diabetes risk
- Meds that may cause rapid glucose rise e.g. steroids, antipsychotics
- Acute pancreatic damage, inc. surgery
-Pregnancy
- High RBC turnover or abnormal haemoglobin (haemolytic anaemia/ haemoglobinopathies)
- Recent blood transfusion
these are all times when HbA1c is not appropriate to take
What groups is HbA1c not appropriate to take from?
Patient factors:
- ALL children & young people
- Pregnancy
- T1DM
- DM Symptoms <2 months
- Acutely ill (i.e. hosp admission) + high diabetes risk
- High RBC turnover or abnormal haemoglobin (haemolytic anaemia/ haemoglobinopathies)
Iatrogenic:
- Meds that may cause rapid glucose rise e.g. steroids, antipsychotics
- Acute pancreatic damage, inc. surgery
- Recent blood transfusion
What blood tests are used for monitoring diabetes?
HbA1C (not T1DM or GDM though) Fructosamine creatinine lipid profile glycaemic records
How often are glycaemic records taken?
QDS e.g. 4x daily –>
before meals and before beds
why is creatinine used for monitoring diabetes?
renal function indicator
What is fructosamine?
a blood test useful for DM monitoring when unable to measure HbA1C
What is HbA1C used for in T2DM monitoring?
is a glycaemic control indicator
as it could be an average of hyper and hypo episodes want to aim for 48-59mmol/mil control or 6.5-7.5% (>48 (6.5%) = DM)
If someone has a hba1c and it is below 42 mmol/mol but they still have symptoms what should they do?
< 42 is normal range for HBA1C
BUT if symptoms present consider glucose test (fasting, random, oral) as they may still be at risk
– communicate risk of developing diabetes & benefits of a healthy lifestyle
–> recheck HbA1C in 3 years
or earlier if clinically indicated
If someone has a hba1c and it is between 42 - 47 mmol/mol but they still have symptoms what should they do?
they are at high risk of diabetes
- -> INTENSIVE lifestyle modification
- recheck HbA1c in 1 year - or earlier if clinically indicated
If someone has HbA1c ≥ 48 mmol/mol and are asymptomatic what do you do?
they are in the DM range e.g ≥48
but as asymptomatic …
– REPEAT HbA1c in 2 weeks
if it is STILL ≥ 48 = dx diabetes – follow diabetes management pathway
if it is < 48 – follow high risk of diabetes
e.g. intense lifestyle modification and recheck HbA1c in 1 year
If someone has HbA1c ≥ 48 mmol/mol and are symptomatic what do you do?
≥ 48 mmol/mol is diabetic, the dx is diabetes so follow diabetes management pathway
NB; w/ T2DM it is likely routine Dx e.g. asymp so TF rememeber about repeating hba1c in 2w unless heart attack etc as DM syx?
