Chemistries Flashcards
basic function tests
hepatic function test, renal function test, thyroid function test, electrolyte function test
what are the basic panels done for each function test?
hepatic: albumin/globulin, alk phos, ALT, AST, GGT, total bilirubin, bile acids, fibrinogen
renal: BUN, creatine
thyroid: T4, T3, TSH, free T4
electrolytes: potassium, calcium, sodium
what to do before collecting a sample for chemistries?
get patient history (fasting, meds, etc), know which samples are needed
which anticoagulant should be used for sample collection of chemistries?
heparin plasma, lithium heparin
no EDTA
what should be done with the chemistry sample after collecting?
centrifuge right away
serum can be kept in the fridge or freezer but make sure it returns to room temp before using
what tests can dehydration effect the results of?
serum or plasma protein, PCV, BUN, urine specific gravity
what effect can the quality of serum/plasma have on the test results?
quality of serum/plasma can cause a false increase in values
icterus serum/plasma
normal for some species
or can be caused by liver disease or hemolysis
hemolysis serum/plasma
usually from handling
lipemia serum/plasma
increased lipids (triglycerides) from metabolic disease, diet, or lack of fasting
advantages and disadvantages of in-house analyzers for chemistries
advantages: will get results sooner
disadvantages: sending out can save money, might not have enough staffing that can do chemistries
Abaxis VetScan for chemistries
uses rotors/cartridges
panels/profiles can’t be customized
step-by-step interface
rotors are expensive
Idexx Catalyst One for chemistries
variety of profiles
uses plastic clips or individual slides
can be customized
no direct interface
expensive
Idexx VetTest for chemistries
variety of profiles
can be customized
interface walks you through the steps
slides are less expensive
Abaxis 1-Stat for chemistries
small and portable: used for mobile procedures and fieldwork
multiple profiles are available
uses cartridges
small samples
2 minute results
not customizable
requires software updates
kidney function
conserve/eliminate water, electrolytes, nutrients, and remove ammonia waste (urea and creatinine)
blood urea nitrogen
principal waste product of protein metabolism
creatinine
muscle waste product
increased BUN and creatinine
azotemia
what is the normal kidney function in terms of BUN and creatinine removal?
BUN and creatinine are primarily cleared by the kidneys through glomerular filtration and excreted in urine with minimal tubule reabsorption
SDMA
symmetric dimethylarginine glomerular filtration
Idexx test
not affected by muscle breakdown
can detect from 40-25% renal dysfunction
uric acid
like a paste, not more soluble than BUN
preferred indicator of kidney function in birds/reptiles as well as Dalmatians
Dalmatians have decreased conversion to allantoin (oxidized uric acid) which is more water soluble than urea so they excrete uric acid
liver function
metabolism of amino acids/carbs/lipids, synthesis of albumin/cholesterol/clotting factors, digestion and absorption of nutrients related to bile formation, secretion of bile and pigments, elimination of toxins and catabolism of drugs
bile
emulsification of fat
absorbs fatty acids and vitamins
pigments (liver)
bilirubin from red blood cells and hemoglobin
liver tests
enzyme leakage tests: ALT/AST
cholestatic tests: ALP/GGT
other: bilirubin, albumin/globulin/A:G ratio, fibrinogen, bile acids, ammonia, cholesterol
ALT test
liver enzyme leakage test
alanine aminotransferase
liver specific
tests for heptocellular damage on dogs, cats, primates
what was ALT formerly known as?
serum glutamate pyruvate transaminase (SGPT)
AST test
liver enzyme leakage test
aspartate aminotransferase
not liver specific
increased AST = some type of liver or muscle damage
what was AST formerly known as?
serum glutamine oxaloacetate transaminase (SGOT)
GD or GLDH
glutamine dehydrogenase
interface between carbohydrate and amino acid metabolism
highly concentrated in large animal and bird livers
levels return to normal 24 hours after eating
creatine kinase (CK) or creatine phosphokinase (CPK)
specific for muscle damage
can’t tell you which muscle is damaged
elevation of AST and/or ALT with normal CPK levels suggest hepatocellular injury but could be prior muscle injury and CPK has already returned to normal