Diabetes diagnosis

Pathophysiology

Type 1: immune-mediated beta cell destruction, usually leading to absolute insulin deficiency
Type 2: spectrum from insulin resistance with relative insulin deficiency, to predominantly insulin secretory defect with insulin resistance
Type 3:
- A - genetic defects of beta cell development or function characterised by mutations
- B - transient neonatal diabetes
- C - diseases of the exocrine pancreas
- D - genetic defects in insulin action
- E - endocrinopathies
- F - drug or chemical-induced
- G - infections
- H - uncommon forms of immune-mediated diabetes
- I - other genetic syndromes sometimes associated with diabetes
Type 4: gestational diabetes

Can technically be diagnosed by any one of the below criteria, but note that risk of complications is on a continuous rather than discrete scale
Diagnosis withdrawn when criteria return to normal

	Normal glucose tolerance	Pre-diabetic hyperglycaemia	Diabetic
Random BSL (with symptoms of diabetes)			>11.1
Fasting BSL (no caloric intake for 8 hours)	<5.6	5.6-6.9	>6.9
HbA1c	<5.6%	5.7-6.4%	>6.4%
2-hour BSL after a glucose challenge	<7.8	7.8-11	>11

Acute hyperglycaemia: polyuria, polydipsia, weight loss, fatigue, weakness, blurry vision, frequent superficial infections, and slow healing of skin lesions after minor trauma
Screen for chronic complications
- Microvascular
  - Eye disease - retinopathy and macular oedema
  - Neuropathy - sensory, motor and autonomic
  - Nephropathy (albuminuria and declining renal function)
- Macrovascular
  - Coronary heart disease
  - Peripheral arterial disease
  - Cerebrovascular disease
- Other
  - GIT - gastroparesis, diarrhoea
  - Genitourinary - uropathy, sexual dysfunction
  - Dermatologic
  - Infectious
  - Cataracts
  - Glaucoma
  - Cheiroarthropathy
  - Periodontal disease
  - Hearing loss
Screen for comorbidities: cardiovascular disease, HTN, dyslipidaemia, OSA, fatty liver, OP, low testosterone in men, depression