Flashcards in Intro to Biochem Deck (50)
List 5 clinical pathology tests
What is biochemistry used for?
Evaluate different organ systems
Measure enzymes, metabolites etc.
Use with urinalysis and CBC
What fraction of blood is evaluated for buichemistry?
Serum (lacking clotting factors but means nothing is added to tube) vs. plasma which would have clotting factors (inc fibrinogen)
When may plasma be used?
Heparinized plasma used for reptiles and birds due to small sample size
What colour are serum tubes?
Red or brown
What additional chemicals may be added to serum tubes
Serum separator separates cells from serum to prevent RBCs metabolising glucose etc. affecting serum levels
What is another term for serum?
How should serum be stored?
4 degrees c
How is plasma collected?
Into EDTA, Heparin or citrate tubes
Separate plasma from cells by centrifuge
Store at 4 deg C
What does within reference interval (WRI) mean?
95% animals will be within the range when healthy
If multiple parameters assessed ^ chance of finding an out of range result.
What are blood levels of analytes dependent on?
Amount produced and amount excreted.
Remember if ^ production and concurrent ^ excretion, values will appear within normal range
Where is total protein measured from?
Serum or plasma
Which value of total protein will be higher (serum v plasma)?
Plasma greater as includes fibrinogen
What does total protein consist of?
Albumin and globulins
How may total protein be measured? How does this mean results may be affected?
Refractometer (in clinic) or colorimeter (in lab)
Results may be falsely raised by icterus, hemolysis and lipemia
When may increased total protein be seen?
When may decreased total protein be seen?
Loss (nephropathy or enteropathy)
How is albumin measured? In which species is this unrelable and how is this overcome?
Dye binding method
Unreliable in birds - use electrophoresis instead
When is increased albumin seen?
When is decreased albumin seen?
Loss (renal, hemorrhage, GI)
v synthesis (liver)
3rd spacing (effusions)
How is globulin concentration calculated?
Total protein - albumen
(Globulins = all remaining proteins)
How would individual globulins be separated and what may this show?
If polyclonal shows inflamation (eg. FIP)
If monoclonal shows neoplasia (eg. plasma cell tumour)
What 3 things are evaluated when looking at the liver?
What 2 enzymes, detectable in the blood, does the pancreas secrete most of? Are they pancreas specific?
Amylase and lipase
Not pancreas specific - can come from other sources
When are increases in amylase and lipase seen?
Pancreatitis - 4/5 fold increase in dogs, NOT cats
Which two analyses must be carried out to evaluate urinary system function?
Serum/plasma chemistry and urine
What are urea and creatinine indicators of? What else may they be associated with?
Urea produced by liver so reflects liver function too
Creatinine produced in muscle breakdown (recumbency and IM injections can ^)
What is azotemia and what are the possible causes?
^ urea and creatinine in circulation
- pre-renal: dehydration
- renal: renal disease
- post renal: obstruction
How may the cause of azotemia be diagnosed?
Check urine specific gravity - measure of kidneys ability to concentrate urine
If USG low, renal funciton is impaired
If USG normal, dehydration is the cause