Type 1 DM

Question 1

What is the significance of genetic disposition to get T1DM?

Answer 1

• 0.5% background risk
• 1-2% if mother affected
• 3-6% if father has affected
• 6% if sibling has affected
• 36% if monozygotic twin affected
• associated with HLA antigens
  
  • HLA DR3-DQ2 and DR$-DQ9 predispose and individual to the disease
  • 90% of Scandinavians with T1DM are positive to one or both genetic mutation

Question 2

What is the pathophysiology of T1DM?

Answer 2

• Beta-cell events trigger an autoimmune response
• antibodies to insulin or glutamic acid decarboxylase(GAD) appear first
  
  • Insulinoma-associated protein (IA-2) and cation efflux Zinc transported (ZnT8) antibodies follow after
• there is selective immune beta-cell destruction

Question 3

What is this an image of?

Answer 3

• autoimmune destruction: Insulitis

Question 4

What is the autoimmune trigger?

Answer 4

• viral infection (Coxsackie)
• ER stress
• Cytokines

Question 5

What diseases are associated with Type 1 Diabetes?

Answer 5

• Coeliac disease
• Hypothyroidism
• Grave’s disease
• Addison’s disease
• Hypogonadism
• Pernicious anaemia
• Vitiligo
• Autoimmune polyglandular syndromes

Question 6

What are the symptoms of T1DM?

Answer 6

• Lethargy
• Polyuria
• Polydipsia
• Blurred Vision
• Candida infections
• Weight Loss
• Ketosis/ Ketoacidosis
• Death

Question 7

What assessments are needed for the diagnosis of T1DM?

Answer 7

• Age of onset
• Rapidity of onset
• Phenotype
• PMH
• FH
• Weight loss
• Ketosis
• GAD/IA2/Zinc transporter 8 antibody positive
• C-Peptide

Question 8

What is C-peptide?

Answer 8

• a product of the cleavage of Proinsulin
  
  • Proinsulin –> Insulin + C-peptide

Question 9

How is insulin administered?

Answer 9

• given parenterally
  
  • subcutaneously
    
    • specific injection sites
  • inhaled
  • mucous membranes
• there is the Basal bolus regimen
  
  • rapid-acting insulin pre-meal (bolus)
  • long-acting background insulin (basal)

Question 10

What factors affect Blood glucose?

Answer 10

• Diet
• Injection site
• Temperature
• Excercise
• Illness
• Stress
• Alcohol
• Menstrual cycle

Question 11

What are the symptoms of Hypoglycaemia?

Answer 11

• Autonomic symptoms
  
  • Palpitation, sweating, tremor
• Neuroglycopaenic symptoms
  
  • confusion
• Mild and severe
  
  • Mild hypoglycaemia inevitable with good control
  • Loss of warning signs

Question 12

Go over the monitoring T1DM patients should do

Answer 12

• Glucose monitoring
  
  • Minimum 4 x daily
  • Driving
  • Unwell
  • Hypoglycaemia
• CGMS (continuous glucose monitoring system)
• Ketone monitoring
  
  • blood (beta-hydroxybutyrate)
  • urine (acetoacetate)

Question 13

What monitoring should the clinician do?

Answer 13

• HbA1c (glycated haemoglobin)
  
  • Reflects glucose over last 3 months
    
    • patients should be seen at least every 3 months
  • Weighted towards last 6 weeks
  • Affected by red cell lifespan
• HbA1c may be falsely high in low rbc turn over
  
  • iron, vitB12 or folate deficiency
• HbA1c may be falsely low in high rbc turn over
  
  • sickle cell disease