Endo 14 - Pathophysiology and Treatment of Type 1 Diabetes Mellitus Flashcards
(49 cards)
Name a form of Type 1 diabetes that presents late
latent Autoimmune Diabetes in adults - LADA
State 2 monogenic causes of diabetes
- Mitochondrial diabetes
- Maturity onset diabetes of the young - MODY
Which 3 endocrine disorders can diabetes also present with?
Phaeochromacytoma
Cushing’s
Acromegaly
How do phaechromacytoma, cushing’s and acromegaly cause diabetes?
cause hyperglycaemia
What triggers type 1 diabetes?
Environmental trigger with a genetic predisposition
What is the mechanism of T1DM?
autoimmune destruction of islet cells
Which type of diabetes has a bigger genetic component?
T2DM
What can be measured in the blood to give an indication of insulin function?
C-peptide
Low C-peptide =
insulin deficient
Describe the pathogenesis of T1DM?
Gradual autoimmune destruction of beta cells
so gradual fall in insulin and c-peptide
Loss of first phase insulin
eventual destruction of all beta cells from auto-antibodies
Why is T1DM described as a relapsing-remitting disease?
beta cell mass reduces then stabilises
What is the importance of the autoimmune basis of T1SM?
Increased prevalence of other autoimmune disease e.g. thyroid
What are the histological features of T1DM?
Lymphocyte infiltration of beta cells
On which chromosome is HLA found?
Chromosome 6
Which alleles on HLA convey a risk of diabetes?
DR alleles
DR3/4 MOST RISK
What are the two most significant markers of diabetes?
Islet cell autoantibodies
Insulinoma-associated-2-autoantibodies
State some of the symptoms of T1DM?
Polyuria Nocturia Polydipsia Blurring of vision Thrush Weight Loss Fatigue
What are the signs of T1DM?
Dehydration Cachexia Hyperventilation Smell of ketones Glycosuria Ketonuria
What are trigylcerides broken down into?
Glycerol + Fatty acids
What does insulin have a negative effect on?
- hepatic glucose output
- protein breakdown in muscle
- ketone body generation in liver
- glucerol release from fat cells
What does insulin have a positive effect on?
Glucose uptake by tissues
So what happens to glucose in insulin deficiency?
Hyperglycaemia as glucose in circulation not taken up by tissues
State 4 other hormones that increase hepatic glucose output?
- Catecholamine - adrenaline/noradrenaline
- cortisol
- glucagon
- growth hormone
Describe how insulin deficiency leads to diabetic ketoacidosis?
insulin has a suppressive effect on hepatic ketone body generation
without insulin, fatty acids go to liver where they are used to produce ketone bodies
