T1DM Flashcards
What is T1DM?
Autoimmune condition that destroys pancreatic beta cells, leading to a reduced or no production of insulin
What is the key difference between T1DM and T2DM?
T1DM is autoimmune destruction of islets leading to total insulin insufficiency,
T2DM is insulin resistance leading to relative insulin deficiency (however some overlap)
What is it called when T1DM presents later in life?
LADA - latent autoimmune diabetes in adults
What is an example of monogenic diabetes?
MODY - maturity onset of diabetes of the young
What are the stages of T1DM development?
Genetic predisposition,
environment trigger leading to immune abnormalities (production of autoantibodies),
decreased insulin release,
decreased C-peptide
Why is insulin not used as a marker for assessing T1DM?
Shorter half life than C-peptide (hepatic metabolism) // insulin medication will affect readings
How will you be able to observe immune infiltration of the islets on a microscope?
Macrophages surrounding islets, low density of cells within islets (destruction)
What immune cells are involved in T1DM immune destruction?
CD4 T cells and CD8 T cells
Do patients with T1DM lose all beta cells?
No - some continue to make small amounts of insulin just insufficient levels
Which alleles are responsible for genetic susceptibility to T1DM?
HLA-DR allele: DR3 and DR4 (human leukocyte allele)
What are 4 environmental triggers that can cause T1DM?
Enteroviral infections,
gut microbiota,
seasonal variation,
cow milk protein
What are 4 autoantibodies in the pancreas and how are they detected?
Sera is used for detection -
Insulin Autoantibodies (IAA) ,
Glutamic acid decarboxylase (GAD-65) , (widespread NT)
insulinoma - associated 2 autoantibodies (IA-2A) ,
Zinc-transporter 8 (ZnT8)
Measure antibodies at diagnosis as that is when they are most likely to be positive.
What are 7 symptoms of T1DM?
Polyuria, Nocturia, Polydipsia, Blurred Vision, Recurrent Infections, Weight Loss, Fatigue
Why would you get blurring of vision in T1DM?
Glucose in the aqueous humour, water pulled in, the eye swells distorting light, blurry
What are 6 signs of T1DM?
Dehydration,
Cachexia (muscle wasting),
Hyperventilation,
Ketone Smell,
Glycosuria,
Ketonuria
Why do you get cachexia in T1DM?
Lower insulin stimulates proteinolysis (for amino acids and energy), so muscle wasting occurs
What is the effect of T1DM on lipolysis?
Lipolysis is inhibited by insulin, as insulin is low, lipolysis will increase
What is lipolysis and what is the consequential effect of it?
Non-esterified fatty acids go through beta-oxidation pathway leading to the production of ketone bodies (higher ketone levels in blood)
What is the impact of insulin deficiency in the liver?
Increased hepatic glucose output (gluconeogenesis) - because low insulin usually means more glucose needed
What are the 4 therapeutic objectives of T1DM?
Maintain glucose levels without excessive hypoglycaemia, restore physiological insulin profile,
prevent acute metabolic decompensation,
prevent microvascular and macrovascular complications