L16 - Type 1 DM Flashcards
prevalence?
peak onset?
genetic predisposition?
where more prev?
incr. 0.5% adolescence white caucasian seasonal variability more prev at northen latitudes
Genetic predisposition
which family members incr risk and how much
which antigen is it associated with
what percent of what country is v high for this
0.5% background, 1-2 mum, 3-6 dad, 6 sibling, 36 monozygotic twin
associates with HLA antigen
DR3-DQ2 and DR4-DQ8 predispidose
90% scandinavian positive for 1 or both
Pathophysiology
what cells do what
Beta cell events trigger autoimmune response
antibodies to insulin or GAD generally appear first then IA2, Zn2+ transporter 8
leads to selective immune beta cell destruction
Selective evolution of T1 DM
what leads to what and how and when do B cell mass vary with time
genetic predisposition —> ENVIRON TRIGGER insulitis —-> pre diabetes —> diabetes
after environ trigger, b cell mass steadily decr
Autoimmune triggers
examples
Viral infection (Coxsackie)
ER stress
Cytokines
Associations with Type 1 Diabetes
Coeliac disease Hypothyroidism Grave's disease Addison's disease Hypogonadism Pernicious anaemia Vitiligo Autoimmune polyglandular syndromes
symptoms of t1 dm
Lethargy Polyuria Polydipsia Blurred Vision Candida infections Weight Loss Ketosis/ Ketoacidosis Death
What happens with ketones
Metabolisation of protein produce ketones and accumilate in the blood – leads to death: diabetic ketoacidosis
Diagnosis of Type 1 Diabetes
Age of onset Rapidity of onset Phenotype PMH Weight loss Ketosis GAD/IA2/Zinc transporter 8 antibody positive
C-Peptide
what is c peptide
produced in 1:1 molar ratio with insulin
need adequate stimulus for secr
INSULIN
what type of hormone
how is it administered
what types
Necessary for survival ' Peptide hormone needs to be given parenterally ' Subcutaneously ' Inhaled ' Mucous membranes
Various types
• Primary structure (animal, human, analogue)
• Duration of action (addition of protamine, altered
solubility, fatty acid chain)
• Strength: (100, 200, 300, 500 Units/ml)
INSULIN
injection sites
what is physiological insulin secr like
upper outer arms
lower abdomen
upper outer thighs
buttocks
3 peaks after meals
typical insulin regimens
what are the types and what are they like
Basal bolus regimen
• Rapid acting insulin pre-meal (bolus)
• Long acting background insulin (basal)
Balanced regimen
Rapid acting insulin reflects CHO intake
Factors affecting blood glucose
Glucose Diet Injection site Exercise Illness Stress Alcohol Menstrual cycle
Hypoglycaemia
autonomic and neuroglycopaenic symptoms
this and T1 DM
Autonomic symptoms
Palpitation, sweating, tremor
Neuroglycopaenic symptoms
confusion
Mild and severe
Mild hypoglycaemia inevitable with good
control
Loss of warning signs
