Flashcards in Biochemistry and Urinanalysis Deck (28):
Why is it important to use serum if possible when performing boichemistry?
Anticoagulants can interfere with some tests
What does a serum separator tube contain?
A gel which separates away the cells
How can serum be seperated?
Centrifuging and then collecting the supernatant
Serum Seperator tubes
How is plasma collected?
put in an anticoagulant and will need to centrifuge
With a complete biochemistry profile, what is important to consider with reference to RIs?
RIs represent about 95% of normal animals, so with more tests, it is more likely that a healthy animals result will fall outside of the RI
What concept should be remembered when interpreting biochemistry results?
There is a balance between factors going in and factors coming out.
What does total protein consist of?
Globulins & Albumin. Fibrinogen if measuring plasma
Why is it important to look at the colour of plasma when assessing total protein?
Because TP is assessed by a refractometer/colorimiter. So Icterus, haemolysis and lipemia can affect the result.
What may cause increased and decreased TP?
Inc - dehydration (falsely increased), inflammation, neoplasia
Dec - dilution, loss, decreased synthesis
What causes decreased albumin?
How could neoplasia and inflammation be distinguised?
Polyclonal (inflammation) or monoclonal (neoplasia)
How is the liver assessed?
What may cause increased pancreatic enzymes? Are these always a reliable indicator of pancreatic function?
Pancreatits (dogs) and renal disease (cats). Not specific to pancreas as they can come from other sources.
What is important to remember when assessing renal function?
Look at blood results AND urineanalysis
What are the things to look at when assessing kidney function?
Creatinine (n.b. may be increased in muscly animals)
How can pre-renal, renal and post renal be distinguished?
Pre-renal will see no urinary changes.
What are causes of azotemia in pre-renal, renal and post-renal cases?
Pre - dehydration
Renal - renal disease
Post - obstruction
What will a healthy kidney do?
It will still concentrate urine (specific gravity)
Give a normal USG for:
Why is urea not a reliable indicator of renal function in a cow?
They can secrete urea into their saliva so urea levels can be influenced by high protein meals or GI bleeding
What does one need to remember when assessing sodium levels?
It is influenced by water intake, water loss and intake of the metabolite itself.
What is increased potassium levels associated with?
Renal failure (failure to clear) and hypoadrenocorticism
What are decreased potassium levels associated with?
Other than renal dysfunction and vomiting/diarrhoea, what else influences potassium balance?
When are changes in chloride without concurrent changes in sodium likely to occur?
With vomiting or with changed in acid-base status.
Iodine/Bromide salts (iatrogenic) can also affect the number on the machine
When should free calcium levels be checked and why?
If total calcium is raised/decreased as most calcium is bound to albumin so total calcium levels are affected by albumin levels. If a change in total calcium is not accompanied by a change in albumin levels.
Which other mineral is affected by PTH levels?