Diabetes Module Flashcards
differentials for T1DM?
T2DM
diabetes insipidus
hypercalcaemia
UTI
presentation of diabetes insipidus?
unquenchable thirst
excessive urination
prevalence of diabetes insipidus?
very rare
what test is done to look for diabetes insipidus? what result is a positive test?
fluid deprivation test
if fluid output did not decrease it’s DI
UTI clinical presentation?
frequent urination
painful urination
foul smelling urine
why is hypercalcaemia on the differential for T1DM?
can get increased urine frequency and is very dangerous so should exclude
clinical presentation for hypercalcaemia?
groans (constipation)
moans (depression/fatigue)
bones (sore)
stones (kidney)
how is glucose normally absorbed in the body and where?
it is first passively secreted and then is actively reabsorbed in the kidney
what happens to normal glucose absorption mechanisms when there is too much?
not all of it will be reabsorbed in the kidney so it will be excreted in the urine
when would a random blood glucose be sufficient for diagnosis if the patient has no symptoms?
if they get over 11.1mmol/l twice
main role of HbA1c in diabetes?
to measure long term blood glucose control in known diabetics
name 2 diabetes investigations that arent essential for diagnosis?
HbA1c
islet antibodies
what are the normal glucose concentration ranges?
3.6-5.8mmol/l
how many hormones regulate blood glucose?
5
why is hyperglycaemia more common than hypoglycaemia?
4 hormones increase plasma glucose concentration whereas only 1 (insulin) decreases it
what biochemical process does insulin stimulate?
glycogenesis
what biochemical processes does insulin inhibit?
glycogenolysis
gluconeogenesis
lipolysis
what does insulin do to fatty acids?
encourages entry of fatty acids into adipose tissues of the body
promotes chemical reactions that use fatty acids
what does a feedback loop mean?
controlled through its own action
where is insulin made?
beta cells
what happens once insulin is secreted?
stimulates uptake of glucose in peripheral tissues = less glucose in the blood = insulin stops secreting
what things other than the feedback loop stop insulin from being released?
sympathetic nervous system eg during exercise
adrenaline
name the 4 hormones that increase blood glucose levels
glucagon
adrenaline
cortisol
GH
why are diabetic patients tired alot?
poor glycaemic control
why do alot of T1D’s experience weight loss?
increased lipolysis
why do diabetic patients get visual blurring?
glucose can be absorbed by the lens of the eye causing it to change shape
infections in which areas are most common to diabetics?
soft tissue
GU (thrush)
chest
what is kussmaul breathing?
hyperventilation as a result of excessive ketones in blood
what diabetes is kussmaul breathing foudn in?
T1
can you use oral glucose lowering drugs in T1 patients?
no
how should diabetic patients inject their insulin?
into the fatty tissue of their abdomen; rotate the needle as they inject
is an insulin pump first or second line?
second
what birth defect are children with diabetic mothers most liekly to get?
spina bifida and other CNS deformities
do babies with diabetic mothers differ in size from normal babies?
tend to be bigger
when is diabetes the most teratogenic during pregnancy?
8 weeks
can glucose or insulin cross the placenta?
glucose
why are babies with diabetic mothers bigger?
glucose crosses the placenta and if the mother has bad diabetic control it will give the baby too many nutrients
why are babies of diabetic mums at a higher risk of hypo?
used to a high amount of insulin so are producing lots of insulin and when this is stopped they may get hypo
is the risk to monozygotic twins having a concordance higher in T1DM or T2DM?
T2DM
is metformin safe during pregnancy?
yes
what birth risks should be made to a diabetic?
higher risk of stillbirth, preeclampsia, maternal death
is there a correlation between age of diagnosis and decreased life expectancy?
yes
clinical requirements for a metabolic syndrome diagnosis?
impaired glucose regulation/diabetes insulin resistance hypertension triglycerides >1.7mmol/l glucose intolerance obese
what is the risk of a woman with gestational diabetes getting type 2?
30%
what is acromegaly?
excess GH
what is the link between acromegaly patients and diabetes?
1/3rd get it
what test is usually done to check for both acromegaly and diabetes in acromegaly patients?
GTT
what is cushings?
excess cortisol
can diabetes associated with acromegaly and cushings be reversed?
yes potentially if the diseases are controlled well
why should a patient with T2DM’s protein intake be assessed?
too much protein can overload the kidneys
how could you encourgae someone in tayside to exercise?
free membership
diabetic exercise classes
what route are sulfonylureas taken?
orally
why can’t T1DM patients have sulfonylureas?
must be functioning beta cells
main risk of sulfonylurea drugs?
hypoglycaemia
what other drugs can interfere with the effectiveness of sulfonylurea drugs?
corticosteorids
thiazides
anti-psychotics
what type of drug is metformin?
biguanide
why is metformin good for type 2 diabetics?
suppresses appetite and T2’s are usually overweight
prevents absorption and production of glucose
initiates glycolysis
side effects of metformin?
lactic acidosis nausea vomiting diarrhoea metallic taste
what comorbidities should you avoid giving metformin in?
renal failure alcoholism cirrhosis chronic lung disease cardiac failure
what do thiaxolidinediones do?
bind to receptors in the nucleus and prevent gene expression
name the only TZD licensed in the uk?
pioglitazone
when should you give insulin in T2DM?
as a last resort
why is insulin dose decreased if the patient has renal failure?
insulin is excreted by the kidneys
the somogyi effect can occur when a patient is on what antidiabetic medication?
insulin
what is the somogyi effect?
hyperglycaemia prouced by the body in response to hypo straight after insulin injection
what tissues are particularly insulin independent?
retina
nerves
blood vessel walls
what does insulin independent mean?
cannot regulate glucose influx so cant control their BGL
what is the poyol pathway?
biochemical pathway used by insulin indeoendent tissues to decrease their BGL
when will the poyol pathway be activated?
presence of raised intracellular glucose
does glucokinase or aldose reductase have the higher KM?
aldose reductase
what does aldose reductase do?
converts glucose into sorbitol in the poyol pathway
what are you looking for from taking blood in a T2DM patient?
HbA1C
what should you look for in a patient’s urine who has T2DM?
creatinine
albumin
what would proteinuria indicate in a diabetic patient?
kidney damage
what could kidney damage in T2DM be from?
diabetic nephropathy
hypertension
is glomerular filtration increased or decreased in diabetes?
increased
what increases intraglomerular pressure in the kidneys? what is its consequence?
hypertrophic, overworked kidneys
afferent arteriole of the kidneys dilates
= glomerular sclerosis
what are the effects of glomerular sclerosis on the kidneys?
thickening of basement membrane
disruption of normal protein cross links so large molecules can get through = worse filter
leading cause of chronic renal failure?
diabetic nephropathy
what would increased creatinine indicate?
ACUTE renal failure
how often is creatinine measured?
annually
what pathway is responsible for the vascular complications in T2DM?
poyol pathway
what does hypertension do to the kidneys?
damages glomeruli causing proteinuria
what is the BP target for most diabetics?
less than 140/80mmHg
what is the BP target for diabetic patients at risk?
less than 130/80mmHg
which vascular change is characteristic of diabetes?
capillary microangiopathy
what is the effect of capillary microangiography on the body?
thickened, permeable and dilated small blood vessels causing microaneurysms and increased passive diffusion of proteins
what vascular complication causes retinpathy, nephropathy and peripheral neuropathy?
capillary microangiopathy
good screening questions to ask at review?
snacking between meals
compliance
what condition could be causing dry feet and calluses from diabetes?
peripheral nueropathy
cause of distended veins at the foot in someone with diabetes?
peripheal neuropathy
name the 3 types of neuropathy that can occur in diabetic patients?
hyperglycaemic
acute painful diabetic
distal symmetrical
which neuropathy tends to occur in diabetics with poor glycaemic control?
hyperglycaemic neuropathy
clinical presentation of hyperglycaemic neuropathy
discomfort in lower legs
when is a patient most likely to get acute painful diabetic neuropathy?
when they have weight loss and bad glycaemic control
most common neuropathy?
distal symmetrical
which neuropathy presents with the glove and stocking sensation?
distal symmetrical
what si the glove and stocking sensation
sensation reduced over extremities of limbs
what would you find on the feet of someone with DSN?
warm, dry feet
foot ulceration
oedema
why does diabetic retiniopathy happen?
capillary microangiopathy
why do you get dry feet in neuropathy?
nerve damage stops sweating
why do you get foot ischaemia in diabetes?
damage to the nerves can lead to arteriovenous shunting which means blood blood bypasses the capillary vessels of the feet
where do neuropathic foot ulcers present?
high pressure areas eg metatarsal heads or big toe
where do ischemic foot ulcers present?
margins of the feet
foot complication of severe neuropathy?
charcot foot
which condition has a bag of bone appearance on x ray?
charcot foot
