Diabetes

Question 1

What is diabetes mellitus?

Answer 1

• Insulin dependence - Resistance to the effects of insulin.

Question 2

What is diabetes insipidus?

Answer 2

• Deficiency of antidiuretic hormone.

Question 3

What is diabetes mellitus type 1?

Answer 3

• Autoimmune destruction of B-cells - probably triggered by a viral infection such as coxsackie or rubella. - Susceptibility partly dependant on HLA gene subtypes (HLA-DR3/4) - Classically starts in childhood though adult onset is not rare.

Question 4

What is diabetes mellitus type 2?

Answer 4

• Peripheral insulin resistance. - B-cells response to glucose delayed or absent. - Insulin concentrations normal or high. - Strong association with lifestyle (obesity)

Question 5

What is gestational diabetes?

Answer 5

• Genetic predisposition - Insulin resistance, probably triggered by hormonal changes of pregnancy and is resolved with delivery. - Risk factors - maternal age, family history of DM type 2, African/north American native, smoking, previous GF, previous baby over 4kg. - Danger to mother - risk of DM type 2 in later life, hypertension, pre-eclampsia, obstructed labour. - Danger to child - risk of DM type 2 in later life, risk of obesity in later life, macrosomia, neonatal hypoglycaemia, neonatal jaundice, respiratory distress syndrome.

Question 6

What are the causes of secondary diabetes mellitus?

Answer 6

• Chronic pancreatitis - Haemochromatosis - Cystic fibrosis - Pancreatic surgery - Endocrine disease (Cushings syndrome) - Drug therapy (corticosteroids)

Question 7

What are the symptoms of DM type 1?

Answer 7

• Polyuria - Polydipsia - Hunger - Weight loss

Question 8

How do you diagnose DM?

Answer 8

• Fasting plasma glucose level at or above 7.0mmol - Plasma glucose at or above 11.1mmol - 1-2hours after glucose load.

Question 9

What are the acute presentations of DM?

Answer 9

• Ketacidosis - rapid breakdown of fat and protein release ketones (including acetone), can lead to coma/death. - Hyperasmolar nonketotic state - severe dehydration, DM type 2, can lead to coma/death. - Hypoglycaemia - insulin overdose, generally accidental. - Diabetic foot - can lead to generalised sepsis or death.

Question 10

What is the chronic presentation of DM?

Answer 10

• Macrovascular - ischaemic heart disease, stroke, peripheral vascular disease. - Microvascular - Retinopathy, neuropathy, nephropathy. - Cataracts.

Question 11

What is diabetic retinopathy?

Answer 11

• Proliferation of blood vessels in the retina - retinal haemorrhages. - Muscular oedema - fluid exudation into retina.

Question 12

What is diabetic neuropathy?

Answer 12

• Microangiopathy of vasa nervosum - peripheral numbness or tingling, occasional neuropathic pain, muscle weakness, autonomic neuropathy (V+D, constipation, impotence, incontinence, anorgasmia, postural hypotension). - Microangiopathy of glomerulus capillaries - pathology (nodular and diffuse glomerulosclerosis) and clinical (chronic renal failure or nephrotic syndrome hypertension).