- The basics
- Hypercholesterolaemia
- HDL - the good cholesterol
- Hypertriglyceridaemia
- Mixed
1. The Basics
Hyperlipidaemia = raised lipids. Lipids come in 4 main 'flavours':
- chylomicrons = carry triglyceride
- LDL = mainly cholesterol (50%, 10% TG) = the 'bad' flavour
- HDL = mainly phospholipid = the 'good' flavour, carry cholesterol back to the liver
- VLDL = mainly triglyceride (60%, 20% cholesterol)
Signs:
- corneal arcus = grey-white ring around cornea
- xanthelasma = yellow collection of cholesterol under skin
- xanthomata = 'lumps' of cholesterol
- eruptive xanthomata = small yellow-orange papules that appear all over body
- lipaemia retinalis = 'creamy' appearence of blood vessels on fundoscopy
So lets look first at cholesterol and hypercholesterolaemia.
2. Hypercholesterolamia
a. Familial
- LDL receptor dysfunction
- cholesterol 7.5-16
- raised LDL
- tendon xanthomata, corneal arcus and xanthelasma
- heterozygous prevalance 1/500 --> MI in 40s
- homozygous --> MI in 20s
- Polygenic hypercholesterolaemia
- cholesterol 6.5-9
- raised LDL
- xanthelasma and corneal arcus
b. Acquired
- nephrotic syndrome
- renal transplant
- cholestasis
- hypothyroidism
3. HDL
HDL is 'good' cholesterol
It is higher in:
- thin people
- exercise
- oestrogens
- alcohol
- low triglycerides
It is lower in:
- obesity
- sedentary states
- post-puberty males
- smoking
4. Hypertriglyceridaemia
a. Familial
- failure to metabolise chylomicrcons
- features include:
- eruptive xanthomata
- lipaemia retinalis
- retinal vein thrombosis
- pancreatitis
- hepatosplenomegaly
b. Secondary
- diabetes
- obestiy
- alcohol
- chronic renal failure
- liver disease
- drugs such as thiazides, beta blockers or oestrogens
5. Mixed hyperlipidaemia
- Look for palar xanthomas and tuberous xanthomas
After that wordy and depressing battle, lets move on to treatment of hyperlipidaemia...
