T1DM

Question 1

What is T1DM

Answer 1

Metabolic disorder characterised by an absolute deficiency of insulin due to the autoimmune destruction of pancreatic Beta cells

Question 2

What is the overlap between T1 and T2 diabetes

Answer 2

Some T1DM patients also have obesity, predisposing them to a relative insulin deficiency as well as absolute. 10% of T2DM patients also have autoantibodies in their blood therefore relative destruction of Beta cells

Question 3

What is LADA

Answer 3

Late onset Autoimmune Diabetes in Adults - often mistaken for T2DM - presents before 50 years old however acutely and patients typically have a normal BMI

Question 4

What is MODY

Answer 4

Autosomal dominant condition where patients under 25 develop type 2 diabetes

Question 5

Explain the metabolic consequences that arise from an absolute insulin deficiency

Answer 5

• Insulin deficiency means that peripheral muscle and adipose tissue cannot take up glucose to use - we get the secretion of counter regulatory hormones such as glucagon, adrenaline and growth hormone.
• Our body enters starvation mode, we get gluconeogenesis, glycogenolysis and ketogenesis. This results in hyperglycaemia (micro/macrovascular complications) and ketoacidosis

Question 6

What genes may be linked to T1DM

Answer 6

HLA

Question 7

When does T1DM usually present

Answer 7

Usually childhood

Question 8

How does T1DM present

Answer 8

• Usually DKA
• Rapid onset
• Polyuria
• Polydipsia
• Weight loss
• Excessive tiredness
• FHx of autoimmunity

Tired, toilet, thirsty, thinner

Question 9

What is the use of HbA1c with T1DM diagnosis

Answer 9

Not much use - T1DM comes on over the course of days therefore HbA1c has no use

Question 10

How do we diagnose symptomatic patients

Answer 10

• fasting glucose greater than or equal to 7.0 mmol/l OR
• random glucose greater than or equal to 11.1 mmol/l (or 2 hours after 75g oral glucose)

Question 11

How do we diagnose asymptomatic patients

Answer 11

Same tests as symptomatic - however we will need to demonstrate hyperglycaemia on 2 separate occasions

Question 12

If we are in doubt regarding T1DM or T2DM, what further investigations should we do

Answer 12

• C-peptide (reflects insulin - will be low in T1DM)
• Autoantibodies

Question 13

What is the HbA1c target in T1DM

Answer 13

<48 mmol/L - should be monitored every 3-6 months

Question 14

How often should glucose be monitored in T1DM and what are targets

Answer 14

When you wake up and before each meal, as well as before bed - should aim for 5-7 when waking up, and 4-6 before having a meal

Question 15

How do we manage T1DM

Answer 15

Insulin basal bolus regime - SC injections
- Consider adding metformin if BMI > 25