Diabetes mellitus type I Flashcards
drug induced diabetes can be caused by what drugs?
glucocorticoids atypical antipsychotics (clozapine)
definition: T1DM
what are the different types?
destruction of pancreatic beta cells - absolute insulin deficiency
type 1a - autoimmune etiology
type 1b - no evidence of autoimmunity
what are the major susceptibility genes for T1DM? which chromosome?
HLA region on chromosome 6
HLA-DR3 and DR4 haplotypes
MHC II molecules on macrophages
genetic T1DM is highest in what relationship?
monozygotic twins - 50%
offspring with both parents - 30%
the immune response in T1DM is mediated by what process?
inappropriate ADAPTIVE immune response that targets and destroys the beta cells (“mistaken identity”)
what is the immune response in type 1a? type 1b?
type 1a - chronic, progressive T cell mediated immune destruction of pancreas with HLA association
type 1b - no evidence of autoimmunity with NO HLA association
what cell type mediates the beta cell destruction?
T cells
do beta cells undero necrosis or apoptosis in T1DM?
apoptosis
what is the antibodies see in T1DM?
- glutamic acid decardoxylase (GAD65) - 80%
- insulin
- islet cell
- tyrosine phosphatase
when does the disease process begin in T1DM?
months to years before clinical diagnosis
what are hypotheses for environmental factors in T1DM?
- hygiene
- perinatal
- viruses
- diet
what vitamin is thought to play a protective role in T1DM?
vitamin D
diagnosis of T1DM
- formal oral glucose tolerance test
- classical presentation with DKA
- evidence of antibodies
- C peptide
what glucose physiology is occurring during ketoacidosis?
- glucose cannot be taken up by cells
- gluconeogenesis is not suppressed
what protein / fatty acid physiology is occurring during ketoacidosis?
catabolic pathways are activated leading to amino acids and free fatty acids, which further stimulates the process and leads to ketone production
