Diabetes Mellitus Flashcards
what does diabetes mellitus mean?
abnormality of glucose regulation
what does diabetes insipidus mean?
abnormality of renal function
what is the most common type of diabetes mellitus?
type 2
what does the exposure to chronic hyperglycaemia do?
increases the risk of microvascular complications and long-term macrovascular disease
what tests are used for diabates?
random sugar, fasting sugar, glucose tolerance test, HbA1C
what results come back from a random plasma glucose test indicating diabetes?
> 11.1mmol/L on 2 occasions
what does a glucose tolerance test indicate?
if fasting sample indicates impaired fasting glucose
what result from the HbA1C indicates that the patient is diabetic?
> 48mmol/mol (6.5%)
how do you do a glucose tolerance test?
measure the glucose level in blood before giving 75g of glucose and then measure afterwards
what are the ranges of values of normal to diabetic BEFORE giving glucose in the glucose tolerance test?
<6.1 = normal 6.1-7.0 = impaired fasting glucose >7 = diabetes
what are the ranges of values of normal to diabetic AFTER giving glucose in glucose tolerance test
<7.8 = normal 7.8-11.1 = impaired glucose tolerance >11.1 = diabetes
what is type 1 diabetes?
insulin deficiency, the autoimmune destruction of pancreatic B cells
what causes type 1 diabetes?
interplay between genetic and environmental factors
in type 1 diabetes what determines the clinical presentation?
rate of destruction
what is caused by the immune mediated pancreatic B cell destruction?
hyperglycaemia and ketoacidosis
what do low c-peptide levels indicate?
low insulin secretion
what circulating antibodies are present in type 1
GAD, ICA, IAA
what is ketoacidosis?
body cells cannot access glucose for metabolism so they start to metabolise fat which results in ketones as end product
what is the peak incidence of type 1
10-14yrs
what antibodies do type 1 diabetic children have?
higher ICC and IAA
what antibodies do type 1 diabetic adults have?
lower GAD
what are the symptoms of diabetes?
polyuria, polydipsia and tiredness
what is seen with acute presentation of diabetes?
hyperglycaemia with diabetic symptoms and ketoacidosis
what is the stage between normoglycaemia and diabetes?
impaired glucose tolerance
what age group does type 2 diabetes present in?
over 40s
what is type 2 diabetes associated with?
obesity and inactivity, also strong family history
what is type 2 diabetes characterised by?
defective and delayed insulin secretion and abnormal postprandial suppression of glucagon
what is the pathogenesis of type 2 diabetes complicated with?
varying degrees of insulin deficiency, insulin action and genetic and environmental factors
what is type 2 diabetes?
insulin resistance
what factors add to insulin resistance?
defect in insulin synthesis, secretion and action
defect in pulsatile insulin secretion
visceral fat
what are the contributing factors to the defects in insulin synthesis, secretion and action?
B cell response to hyperglycaemia is inadequate, elevated basal insulin levels, failure of gluconeogenesis suppression, insulin stimulated glucose uptake reduced
what metabolic changes occur in type 2
inadequate release of incretins or response to incretins, increased absorption of glucose from GI tract due to increased transporter
what are the multisystem effects of type 2
impaired glucose tolerance, hyperinsulinaemia, hypertension, obesity with abdominal distribution, dyslipidaemia, procoagulant epithelial markers, early and accelerated atherosclerosis
what happens with insulin over time with type 2
the ability to secrete insulin falls
what is the presentation of type 2 diabetes?
polyuria, polydipsia, tiredness, unusual infections, CVS complications (atherosclerosis)
what is important in slowing the decline from IGT?
strict diet and exercise
what medicines induce diabetes?
corticosteroids, immune suppressants, cancer medication, antipsychotics, antivirals
what types of medication induces diabetes?
medicine that interferes with the secretion of insulin or glucagon, medicine which alters tissue uptake of glucose
what other conditions is diabetes related to?
endocrine disease (cushing's, phaeochromocytoma (adrenaline tumour), acromegaly) pregnancy
summarise type 1
younger, thinner, potential family history, diabetic symptoms, ketoacidosis common
summarise type 2
older, obese, strong family history, multisystem complications, rarely get ketoacidosis
