Type 1 Diabetes

Question 1

Type 1

Answer 1

A state of absolute insulin deficiency

mediated by an auto-immune process of varying degree of severity occurring within pancreatic beta cell

Question 2

Aetiology

Answer 2

Idiopathic

Twin studies: monozygotic concordance rate 455

Strong association with HLA

• HLA-DR3
• HLA-DR4

Peak age of onset approx 12 years

Clinical presentation at all ages

Question 3

Pathology

Answer 3

Autoimmune destruction of the beta-cells in the islets of langerhans in the pancreas leading to absolute insulin deficiency

note: Small amounts of insulin can be released up to 5 years after diagnosis

Question 4

Autoimmune Process

Answer 4

Autoantibodies

• GAD 65
• IAA and IA2
• Znt8

Question 5

Clinical Presentation

Answer 5

Acute onset

polyuria
Polydipsia
Weight loss
\+/- ketoacidossi
Thrush
Weakness/fatigue
Blurred vision 

Ketonuria +/- metabolic acidosis

No evidence of microvascular disease at diagnosis

Question 6

Diagnosis

Answer 6

Symptomatic; Random Glucose >11/1 mmol/L

Asymptomatic : Oral glucose tolerance test

• Fasting Glucose: >7mmol/l
• 2hr post-glucose load: >11.1mmol/l

history & Presentation
GAD/IA2 antibodies
Absence of C-peptides (<0.2 mmol/l)

Question 7

Aims of therapy

Answer 7

Prevent hyperglycaemia
Avoid hypoglycaemia
Reduce chronic complications

Question 8

management of T1DM

Answer 8

Blood glucose and ketone monitoring

Insulin
- basal (once daily) and bolus (with meals) regime

Carbohydrate estimation

Self management education

• DAFNE
• Sick day rules

Regular check of prevailing glycemic control
-HbA1c ideal range: 48mmol/L

Continuous Subcutaneous Insulin Infusion (CSII)
- Self administration

Question 9

T1DM Associated conditions

Answer 9

Cystic fibrosis
Wolfram Syndrome
Bardet-Biedl Syndrome

Associated Auto-immune

• Thyroid disease
• Coeliac disease
• Pernicious anaemia
• Addison’s Disease
• IgA deficiency

Question 10

Glucose Monitoring Targets (Children)

Answer 10

On waking and before meals : 4-7 mol/L

After meals: 5-9 mmol/l

Question 11

Glucose Monitoring Targets (Adults)

Answer 11

On waking: 5-7 mmol/L
Before meals: 4-7 mol/L
90 mins after meals: 5-9mmol/L