Describe the etiology of DM I Non-autoimmune (idiopathic) - unknown cause, less
common than autoimmune diabetes
strong genetic component
occurs mostly in people of asian or african descent
Describe the etiology of DM I autoimmune - Genetic factors:
First degree relatives with DM 1
Strongest association with MHC
Environmental factors:
viral infection
H. Pylori
exposure to cow milk proteins
relative lack of Vitamin D
Gradual process of autoimmune destruction of B cells in genetically susceptible
individuals
Natural history of DM I - Long pre-clinical period with B cell destruction, leading to
insulin deficiencies and hyperglycemia
Protein and fat breakdown:
weight loss
high levels of circulating Ketons (Think DKA!)
Pathogenesis of DM I Non autoimmune/Idiopathic - no evidence of B cell autoimmunity,
varying degrees of insulin deficiency
pathogenesis of DM I Autoimmune - Slowly progressive disease that destroys all B cells
of pancreas
How many of the B cells are destroyed with DM I autoimmune? - 80-90% of insulin
secreting B cells int eh slate of lagerhands are destroyed and insulin synthesis declines
What does insulin normally suppress? - Glucagon
What is there a decreased secretion of in DM I? and the result? - amylin - which
increases glucagon production
What is glucagon? - A hormone produced by the a cells of the islets, acts in the liver,
increases blood glucose by stimulating glycogenesis and contributes to hyperglycemia
in DM I.
, What contributes to hyperglycemia in DM I? - lack of insulin and excess glucagon
DM II Etiology - genetic susceptibility (polygenic)
environmental defects in b cell function combined with insulin resistance
associated with long-duration obesity
DM II natural history - compensatory hyperinsulinemia prevents the clinical appearance
of diabetes for many years
decrease in B cell mass and reduction in normal B cell function develops and leads to a
relative deficiency of insulin activity
Pathogenesis of DM II - Defects in uncreative insulin secretion and insulin effects on
target tissues (insulin resistance) = persistent state of hyperglycemia, inducing
metabolic alteration, cell death, and inflammation
What causes insulin resistance? - abnormality of insulin molecule
high amounts of insulin antagonists
down-regulation of insulin receptor
alteration of glucose transporter (GLUT) proteins
What is the most important contributor to insulin resistance and how? - Obesity
adipose tissue releases/produces:
fatty acids
glycerol
hormones
pro-inflammatory cytokines (adipokines)
What are other contributors to insulin resistance? - elevated glucagon
decreased amylin
decreased ghrelin
decreased responsiveness of B cells
Kidney pathophysiology
What are the classic symptoms of DM I? - polydipsia
polyuria
polyphagia
weight loss
fatigue
recurrent infections
prolonged wound healing
general pruritis
visual changes
paresthesias
CV symptoms
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller VasilyKichigin. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $13.48. You're not tied to anything after your purchase.