It affects capillaries of retina, renal glomeruli, and peripheral nerves.

1- Diabetic retinopathy

2- Diabetic Nephropathy

3- Diabetic Neuropathy

Reason:

long standing hyperglycaemia.

Pathogenesis:

Microvasculature (capillaries) shows both:

  1. structural abnormalities due to: A- Hyperglycemia ⇒ inability to metabolize glucose within pericytes ⇒ osmotic damage with increase permeability.

B- Glycosylation (i.e. binding of glucose to wall of blood vessels).

  1. functional abnormalities: A- Increased capillary permeability ⇒ Retinal exudates, Increased urinary loss of albumin .

B- Disturbed platelet function with tendency to aggregate and thrombosis