diabetes mellitus Flashcards
what are the thresholds for diabetes diagnosis
> 7mmol/L fasting plasma glucose
11.1mmol/L 2hr plasma glucose
48mmol/mol HbA1c (5.8%)
*and are set on risk of developing diabetic retinopathy
what is the difference in thresholds for gestational diabetes
they are a lot lower
*are set based of off risk to neonate
what is a useful measure for endogenous insulin
C-peptide
what is C-peptide
it is co-secreted with insulin and is not part of the insulin injection
so if C-peptide is present in the blood it must be coming from Beta cells ie pancreas is still working
T1DM causes
genetic:
MODY
neonatal
Pancreatic disease:
alcohol and chronic pancreatitis
acute pancreatitis
pancreatic cancer
pancreatectomy
CF
Haemochromatosis
can steroids induce diabetes T/F
T
exogenous GLCTCs can cause diabetes ie patients with COPD
what is T1DM
autoimmune destruction of the pancreatic beta cells resulting in beta cell deficiency
onset in children and young adults but
can come on at any age
up to 95% have pancreatic antibodies in blood
requires insulin treatment (fatal if not)
what is T2DM
ranges from insulin resistance with relative insulin deficiency to predominantly an insulin secretory defect with insulin resistance
do not need insulin to survive unlike T1DM
there is no typical person with T2DM
who gets T2DM
obesity and sedentary lifestyle
onset in middle age and elderly
not autoimmune
how does diabetes present
can be asymptomatic
symptoms of high blood glucose:
polyuria
polydipsia
blurred vision - osmotic shift and the lens contracts
genital thrush
fatigue
weight loss
symptoms/complications:
loss of vision
retinal bleeding
how does DKA present
T1DM get it
breath smells like pear drops
why treat diabetes
prevent acute symptoms and life threatening illnesses
to reduce burden of diabetes
microvascular complications
macrovascular complications
what is HbA1c
blood glucose varies continuously - so taken at one point is largely unhelpful
haemoglobin + glucose = glycated (haemoglobin is altered)
amount of glycated haemoglobin is directly linked to exposure to glucose (HbA1c)
RBC turnover about 90 days
A 58 year old Type 1 diabetic presents to his GP complaining of altered sensation in his legs.
Which of the following clinical features would most suggest a diagnosis of diabetic neuropathy?
sensory loss in a stocking distribution
this is a classical feature
which test is useful in differentiating an endogenous from an exogenous cause of hypoglycaemia
serum C peptide
An 18 year old male presents to his GP with a history of tiredness, polydipsia and polyuria.
Which of the following investigation results would on its own would be sufficient to diagnose diabetes mellitus in this patient?
random blood glucose of 12.5mmol/L
one measurement of blood glucose >11mmol/L in a SYMPTOMATIC patient is sufficient to diagnose diabetes mellitus
which medication is most likely to cause a hypo
sulphonylureas ie gliclazide
what’s the first line treatment for diabetic neuropathy
pregablin , duloxetine , gabapentin
for painful diabetes
