This is a common endocrine disorder all over the world. 9% of 140 million prevalence rate in Singapore. It is a heterogenous chronic metablolic disorder characterised by presence of hyperglycemia due to lack of insulin.

It can be due to decrease of insulin, decrease to response to insulin or increase in counter-regulatory hormones.

The chronic hyperglycemia is associated with long-term sequela (an abnormal condition resulting from a previous disease) results in damaging the kidneys, eyes, nerves and blood vessels. These damges is slow and progressive.

It is classified into primary and secondary causes. Primary causes are Type 1 Diabetes (IDDM)- Insulin Depend DM. It is due to destructive of beta cells(autoimmune) or very little or no insulin production. For Type 2 Diabetes (NIDDM)-Non-insulin depend DM, it is due to insuffiecient or insulin resistance (beta cells dysfunction).

The secondary causes are due to pancreatic disease(pancreatits), liver disease(liver cirrhosis) and excess secretion of insulin antagonist (glucocoticoids, catecholamines and growth hormone).

Clinical features: Polydipsia(excessive thirst), Polyphagia(increased hunger) and weight loss, even when eating well.

Pathophysiology: Insulin promotes glucose entry to the cells. In DM, due to lack of insulin=cells can't absorb glucose.

The acute complications: Hyperglycemia, hypoglycemia and diabetic ketoacidosis.

Late complications: Ischaemic heart disease, stroke, peripheral limb ischaemia, eye retinopathy, kidney nephropathy, nerve nephropathy, skin lesion (esp feet-due to damage to bld vessels resulting in foot ulcers and gangrene of toes.)