Clinical biochemistry Flashcards
Why would FBCs be requested?
- Screen for a range of diseases
- Diagnose various conditions, e.g. anaemia, infection
- Monitor a condition/ effectiveness of treatment after diagnosis
- Monitor treatment known to affect blood e.g. chemotherapy or radiotherapy
What is included in a FBC?
White blood cells –> defence against infection and cancer, allergy and inflammation
Red blood cells –> transporters of oxygen through the body
Platelets –> responsible for blood clotting
What is CRP?
C-reactive protein
- An acute phase protein (concentrations increase or decrease by 25% or more during inflammation) produced by the liver
- High levels indicate inflammation in the body
- Reference range is 0-10mg/dL
What is albumin?
- An inflammatory marker/ marker of infection in many chronic disease states e.g. liver and renal disease
- Low levels are found in liver disease, severe inflammation
- High levels are found in dehydration
- Normal range is 35-55g/l
What is an acute phase response?
The body’s response to inflammation resulting in a rise or decrease in plasma concentration of acute phase proteins.
E.g. positive –> CRP, ferritin
Negative –> albumin, tranferrin
Changes in these parameters may be used as markers of inflammation
Why are U&E tests?
Urea and electrolytes
The. most commonly requested biochemistry tests providing essential information on renal function.
Urea is the excretory product of biochemical metabolism. It is synthesised by the liver and is a good marker of acute renal disease.
What is creatinine?
Product of protein breakdown, useful marker of long term renal function
What is renal disease glomerular filtration rate>
Kidney function test
The rate at which blood is filtered by passing over the glomerulus to begin urine production.
Chronic kidney disease is stage 1-5 based on eGFR
What do electrolytes do in the body?
- Help move nutrients into cells
- Help remove waste products from cells
- Maintain fluid balance
- Help stabilise levels of acid and alkali in the body (pH balance)
What is a raised sodium level called?
Why could it occur?
Hypernatraemia
Could be the result of dehydration or persistent diarrhoea
What is low sodium?
Why could it occur?
Hyponatraemia
Could be due to certain medication such as diuretics.
Rare –> from diabetes insipidus
Why might potassium levels be raised?
Name?
Hyperkalaemia
Could be a result of kidney failure
Certain medications can raise potassium levels, e.g. ACE inhibitors which are hypertensive drugs
Why might potassium levels be low?
Name?
Hypokalaemia
Could be result of persistent vomiting or diarrhoea
Also can be due to certain medications
Discuss calcium
Most concentrated in blood.
Some bound to albumin
High levels found with hyperparathyroidism, metastatic calcium, myeloma and dehydration
Low levels found with hypoparathyroidism, vitamin D deficiency, chronic renal failure, hypoalbuminaemia, acute pancreatitis, cirrhosis
Discuss phosphate
An inverse relationship exists between levels of phosphate and calcium, if the serum level of one rises, the other falls.
Plays important role in how the body uses carbohydrates and fats. It is also needed for the body to make protein for growth, maintenance, and repair of cells and tissues.
Phosphorus also helps make ATP