Clinical Pathology - exam 4: clinical chemistry
NEWEST VERSION 2026 \COMPLETE QUESTIONS
AND ACCURATE DETAILED ANSWERS \VERIFIED
100% \GRADED A+ \LATEST UPDATE 2025 -
2026
creatine kinase (CK)
what enzymes are leaked
AST (aspartate aminotransferase)
from damaged muscle?
+/- ALT (alanine aminotransferase)
the gold standard for detection of muscle damage
-> is specific to muscle injury and sensitive (even if minor)
what is creatine kinase (CK)? -> mostly from skeletal muscle (minor amount in cardiac +
smooth)
-> has a short half-life: peak activity w/in 6-12 hours of
acute muscle injury; half-life is 2-4 hrs
non-specific enzyme (leakage enzyme) whose elevation has
good sensitivity for
muscle or liver damage (or hemolysis) in all common
what is aspartate veterinary species
aminotransferase (AST)? -> major sources: muscle damage, hepatocyte damage,
erythrocyte hemolysis
-> longer half-life than CK (~1 day to 1 week)
& takes longer than CK to increase (24-36h)
a hepatocyte cytosolic enzyme (leakage enzyme) w/ low levels
in skeletal muscle
-> if elevated, consider liver first but if also ↑CK & ↑AST, may
what is alanine indicate muscle injury
aminotransferase (ALT)? -> is highly specific for liver, especially in dogs & cats
(very mild activity for muscle; not useful for liver
assessment in horses, cattle, pigs, & birds)
only a mild increase with major muscle injury
creatine kinase (CK)
in muscle damage, (enzyme)
elevates first
, more time has passed since the muscle injury
-> AST has a longer half life (up to
what can ↑AST indicate if CK
1 week) whereas CK peaks within
is normal?
6-12 hours of injury
iron containing protein in muscle
-> if significantly increased, assoc w/ acute, severe muscle
what is myoglobin? injury
-> when released goes through glomeruli of kidney and is
excreted in urine (if ↑↑↑
can cause damage to renal tubular cells)
myoglobin in urine turns urine red-brown/brown
what is myoglobinuria?
-> indicates acute + severe muscle injury
1) hemoglobin: consider if hemolysis, ↓PCV
2) myoglobin: consider if muscle damage, ↑CK
3) intact RBCs: consider source of bleeding
a positive heme on dipstick
can be from presence of what hemoglobin & myoglobin will not separate upon urine
3 things? centrifugation; intact RBCs will separate
-> trauma
-> iatrogenic (IM inj, surgery, trailer ride)
-> thrombosis (feline aortic thromboembolism)
-> vit E/ selenium deficiency
-> toxins (ionophore antiprotozoals)
-> ischemia ("down cow", compartment syndrome)
-> exertional rhabdomyolysis
-> infectious/non-infectious myositis
what are sources of muscle
damage? -> degenerative diseases (muscular dystrophy)
,why is ALT not a useful because of minimal ALT in hepatocytes in species like horses,
indicator of liver function in cattle, pigs, & birds
some species?
highly specific liver enzyme (leakage) especially in horses &
what is sorbitol cattle
dehydrogenase (SDH) -> can also be used in dogs/cats but less commonly available (use
ALT instead)
-> is relatively unstable: refrigerate if delayed >4 hr or freeze if
>24 hr
hepatocyte mitochondrial enzyme (leakage enzyme)
that is highly specific for liver and used mostly in large
what is glutamate animals
dehydrogenase (GLDH)? -> more stable than SDH
(limited availability in US)
increased production of
membrane bound proteins
what is enzyme induction? leads to increased serum
activity
e.g. cholestasis (impaired bile
flow) causes ALP/GGT induction
inducible enzyme w/ several isoforms: L-ALP, B-ALP, C-ALP
-> ↑ALP does not differentiate which isoform is causing
the increase; must determine based on clinical reasoning
what is alkaline phosphatase other liver enzymes↑ ->
(ALP)? likely L-ALP cholestasis -
> likely L-ALP
pred/cushings in dogs ->
likely C-ALP phenobarb -
> likely L-ALP
bone remodeling -> likely B-ALP
liver-alkaline phosphatase (isoform) present in
hepatocytes and biliary epithelium cell membrane
what is L-ALP -> major source of serum ALP activity
-> can be increased w/ cholestasis and/or induced by some
drugs, notably
phenobarbital
, bone-alkaline phosphatase (isoform) present in osteoblasts
-> minor source of serum ALP activity
what is B-ALP?
-> can have mild ↑ALP from bone remodeling: growing
animals, fracture, osteosarcoma
NEWEST VERSION 2026 \COMPLETE QUESTIONS
AND ACCURATE DETAILED ANSWERS \VERIFIED
100% \GRADED A+ \LATEST UPDATE 2025 -
2026
creatine kinase (CK)
what enzymes are leaked
AST (aspartate aminotransferase)
from damaged muscle?
+/- ALT (alanine aminotransferase)
the gold standard for detection of muscle damage
-> is specific to muscle injury and sensitive (even if minor)
what is creatine kinase (CK)? -> mostly from skeletal muscle (minor amount in cardiac +
smooth)
-> has a short half-life: peak activity w/in 6-12 hours of
acute muscle injury; half-life is 2-4 hrs
non-specific enzyme (leakage enzyme) whose elevation has
good sensitivity for
muscle or liver damage (or hemolysis) in all common
what is aspartate veterinary species
aminotransferase (AST)? -> major sources: muscle damage, hepatocyte damage,
erythrocyte hemolysis
-> longer half-life than CK (~1 day to 1 week)
& takes longer than CK to increase (24-36h)
a hepatocyte cytosolic enzyme (leakage enzyme) w/ low levels
in skeletal muscle
-> if elevated, consider liver first but if also ↑CK & ↑AST, may
what is alanine indicate muscle injury
aminotransferase (ALT)? -> is highly specific for liver, especially in dogs & cats
(very mild activity for muscle; not useful for liver
assessment in horses, cattle, pigs, & birds)
only a mild increase with major muscle injury
creatine kinase (CK)
in muscle damage, (enzyme)
elevates first
, more time has passed since the muscle injury
-> AST has a longer half life (up to
what can ↑AST indicate if CK
1 week) whereas CK peaks within
is normal?
6-12 hours of injury
iron containing protein in muscle
-> if significantly increased, assoc w/ acute, severe muscle
what is myoglobin? injury
-> when released goes through glomeruli of kidney and is
excreted in urine (if ↑↑↑
can cause damage to renal tubular cells)
myoglobin in urine turns urine red-brown/brown
what is myoglobinuria?
-> indicates acute + severe muscle injury
1) hemoglobin: consider if hemolysis, ↓PCV
2) myoglobin: consider if muscle damage, ↑CK
3) intact RBCs: consider source of bleeding
a positive heme on dipstick
can be from presence of what hemoglobin & myoglobin will not separate upon urine
3 things? centrifugation; intact RBCs will separate
-> trauma
-> iatrogenic (IM inj, surgery, trailer ride)
-> thrombosis (feline aortic thromboembolism)
-> vit E/ selenium deficiency
-> toxins (ionophore antiprotozoals)
-> ischemia ("down cow", compartment syndrome)
-> exertional rhabdomyolysis
-> infectious/non-infectious myositis
what are sources of muscle
damage? -> degenerative diseases (muscular dystrophy)
,why is ALT not a useful because of minimal ALT in hepatocytes in species like horses,
indicator of liver function in cattle, pigs, & birds
some species?
highly specific liver enzyme (leakage) especially in horses &
what is sorbitol cattle
dehydrogenase (SDH) -> can also be used in dogs/cats but less commonly available (use
ALT instead)
-> is relatively unstable: refrigerate if delayed >4 hr or freeze if
>24 hr
hepatocyte mitochondrial enzyme (leakage enzyme)
that is highly specific for liver and used mostly in large
what is glutamate animals
dehydrogenase (GLDH)? -> more stable than SDH
(limited availability in US)
increased production of
membrane bound proteins
what is enzyme induction? leads to increased serum
activity
e.g. cholestasis (impaired bile
flow) causes ALP/GGT induction
inducible enzyme w/ several isoforms: L-ALP, B-ALP, C-ALP
-> ↑ALP does not differentiate which isoform is causing
the increase; must determine based on clinical reasoning
what is alkaline phosphatase other liver enzymes↑ ->
(ALP)? likely L-ALP cholestasis -
> likely L-ALP
pred/cushings in dogs ->
likely C-ALP phenobarb -
> likely L-ALP
bone remodeling -> likely B-ALP
liver-alkaline phosphatase (isoform) present in
hepatocytes and biliary epithelium cell membrane
what is L-ALP -> major source of serum ALP activity
-> can be increased w/ cholestasis and/or induced by some
drugs, notably
phenobarbital
, bone-alkaline phosphatase (isoform) present in osteoblasts
-> minor source of serum ALP activity
what is B-ALP?
-> can have mild ↑ALP from bone remodeling: growing
animals, fracture, osteosarcoma
