19. Diabetes Mellitus

Question 1

What are the symptoms and signs of DM?

Answer 1

Polydipsia

Polyuria

Poor growth

Fatigue, lethargy

Weight loss - despite normal appetite (can be increased)

Question 2

How is DM diagnosed?

Answer 2

Symptomatic

• Fasting glucose = 7mmol/l
• Random glucose 11.1mmol/l

Asymptomatic = above must be demonstrated on 2 diff occasions

Underlying haemolytic disease = high turnover of RBC which will affect HbA1c - Therefore OGTT = more reliable

Auto-Ab = islet cell-Ab, anti-insulin Ab, antiGlu Ab, anti-IA2

Screen = TFT/thyroid Ab, coeliac disease

Question 3

How is DM classified?

Answer 3

Type 1

Type 2

Gestational (GDM)

Maturity onset diabetes of the young - autosomal dominant (15-25yrs)
- Don’t require insulin - give sulfonylureas

Question 4

Outline T1DM pathophysiology

Answer 4

Pathophysiology = autoimmune, Ab against bet cells of pancreas, islet-associated Ab (IAA)

Question 5

Outline T2DM

Answer 5

Pathophysiology = insulin resistance, insulin def

Risk = older, asian, obesity

Treatment = HbA1c target dependant on anti-DM drug type
- First line = metformin
- Lifestyle = diet control, weight loss, HTN control (ACEi - target 140/80), statin (with 10 yr CVS risk - QRISK2)
‣ GI ( glycaemic index) = low index food
‣ High fibre, low fat, low saturated and trans fat

Question 6

What are the complications of DM?

Answer 6

Macrovascular
- Accelerated atherosclerosis = MI, stroke, TIA, PVD

Microvascular (advanced glycosylation end products)

• Painful neuropathy
• Autonomic neuropathy - gastroparesis, ED
• Nephropathy
• Retinopathy and diabetic CNIII palsy (spare pupil)

Question 7

Outline T1DM Mx

Answer 7

Insulin (basal-bolus, long + short term)

• 0.5-1U/kg/d if prepubertal
• 1.5U/kg/d if pubertal

Daily dose =

• 1/3 rapid acting (novorapid)
• 2/3 long acting (lantus)
• 2/3 given pre-breakfast
• 1/3 given pre-dinner

Refer to paed dietician