Hepatology Flashcards
AST is found in significant quantities in all of the following EXCEPT?
a. Liver
b. Muscle
c. RBC
d. Kidney
Answer: d. Kidney
Source: “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals.” Chapman, SE and Hostutler, RA. VCNA 43, 2013. Pg. 1213.
Of the following enzymes, which has the shortest half-life in dogs?
a. AST
b. ALP
c. GGT
d. ALT
Answer: a. AST
Source: “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals.” Chapman, SE and Hostutler, RA. VCNA 43, 2013. Pg. 1213.
Which of the following statements is true regarding ALT?
a. ALT is both an inducible and a leakage enzyme
b. ALT can be increased due to liver and/or muscle damage
c. In vitro hemolysis can falsely decrease ALT
d. ALT has a half-life of approximately 2-3 hours in dogs
Answer: b. ALT can be increased due to liver and/or muscle damage
Source: Stockham and Scott. Fundamentals of Veterinary Clinical Pathology. 2nd ed. Pg. 650-651
An enzyme created by a post-translational modification of an original gene product is a(n):
a. Isoenzyme
b. Isoform
c. Apoenzyme
d. Holoenzyme
B Isoform
Stockham, S. L., Scott, M. A. (2008), Fundamentals of Veterinary Clinical Pathology. 2nd ed. Ames, Iowa: Blackwell Publishing, pg. 640
Which of the following group of enzymes can originate from both the liver and muscle:
a. ALT, ALP, AST
b. ALT, ALP, LDH
c. ALT, AST, LDH
d. ALT, AST, GGT
c. ALT, AST, LDH
Stockham, S. L., Scott, M. A. (2008), Fundamentals of Veterinary Clinical Pathology. 2nd ed. Ames, Iowa: Blackwell Publishing, pg. 641
Which of the following enzymes has the shortest half-life in the dog:
a. LDH
b. ALT
c. C-ALP
d. L-ALP
c. C-ALP
Stockham, S. L., Scott, M. A. (2008), Fundamentals of Veterinary Clinical Pathology. 2nd ed. Ames, Iowa: Blackwell Publishing, pg. 641
Which chemistry panel may be seen as a result of cholestasis?
a. Hypercholesterolemia
b. Hypocholesterolemia
c. Hyperalbuminemia
d. Hypoalbuminemia
a. Hypercholesterolemia
Reference: Chapman. A laboratory diagnostic approach to hepatobiliary disease in small animals. Small animal Clinics. Pg 1219- 1220
The stimulated increase in production of the enzyme protein via modified transcription, translation, or other processes refers to what term? Increases in serum ALP activity result mostly from this process.
a. Inflammation
b. Induction
c. Proliferation
d. Hemolysis
b. Induction
Reference: Enzymes – Leakage enzymes - Stockham and Scott, Fundamentals of Veterinary Clinical Pathology (2nd Ed.) pp. 644
Elevated ALT would be most likely to be noted in the following clinical diagnoses:
a. Bile duct carcinoma
b. Benign familial hyperphosphatesemia in Siberian huskies
c. Osteosarcoma
d. Copper toxicosis
d. Copper toxicosis
All other diagnoses would result in elevation of ALP.
Reference: Enzymes – Leakage enzymes - Stockham and Scott, Fundamentals of Veterinary Clinical Pathology (2nd Ed.) Pg 651
Which compound is inhibitory to Alkaline Phosphatase and which isoenzymes are inhibited?
a. Levamisole inhibits C – ALP
b. Doxycycline inhibits C – ALP
c. Levamisole inhibits L – ALP & B – ALP
d. Doxycycline inhibits L – ALP & B – ALP
c. Levamisole inhibits L – ALP & B – ALP
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology, 2nd edition, pg. 656
In these two species, _______________ & __________________, colostrum has a high level of GGT. Where did the GGT originate from?
a. Bovine & equine, white blood cells
b. Bovine & feline, prolactin byproduct
c. Canine & bovine, mammary epithelium
d. Equine & canine, intra-mammary bacteria
c. Canine & bovine, mammary epithelium
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology, 2nd edition, pg. 661
Which one of the following statements is accurate?
a. Mild elevation (<2 x Upper Reference Interval) of one hepatic biomarker/enzyme in a dog warrants immediate further diagnostic evaluation.
b. Minimal elevation of ALP and GGT with marked (>5 x Upper Reference Interval) elevation of ALT and AST is indicative of hepatocellular damage.
c. Moderate elevation (3-4x Upper Reference Interval) of ALT and AST are definitively indicative of cholestatic disease.
d. Hepatic enzyme level elevations are definitive diagnostics that do not need to be corroborated by other diagnostic test modalities.
B. Minimal elevation of ALP and GGT with marked (>5 x Upper Reference Interval) elevation of ALT and AST is indicative of hepatocellular damage.
Chapman and Hostutler, “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals,” pg. 1210
The most severe elevations of ALT in serum tend to occur with this category of disease.
A) Hepatic neoplasia B) Biliary tract disease C) Cirrhosis D) Inflammation or necrosis
D) Inflammation or necrosis
Source: Diagnostic Approach to Hepatobiliary Disease, p. 1211
This/these ALP isoform(s) contribute to the increased total ALP activity in serum that is sometimes seen in hyperthyroid cats.
A) B-ALP and L-ALP B) L-ALP C) B-ALP D) C-ALP
B) L-ALP
Source: Stockham and Scott, p. 658
This is the conventional/standard method by which the relative contributions of different ALP isoforms to total ALP activity can be determined.
A) Thermal stability B) Enzyme affinity electrophoresis C) Selective inhibition D) Selective precipitation
B) Enzyme affinity electrophoresis
Source: Stockham and Scott, p. 658
The half-life of canine ALT is ________; the half-life of canine AST is _______.
A. 6 minutes; 1 day
B. 6 minutes; 4-5 days
C. 2-3 days; 1 day
D. 2-3 days; 4-5 days
C. 2-3 days; 1 day
Stockham and Scott, Ch. 12 Enzymes, pg. 641
Skeletal and cardiac muscle are sources of _______ and _______.
A. AST; GGT
B. AST; ALT
C. ALP; GGT
D. ALP; ALT
B. AST; ALT
Stockham and Scott, Ch. 12 Enzymes, pg. 642
Which one of the following statements is true regarding ALT and AST?
A. Phenobarbital may cause increased levels of AST.
B. AST is a more specific indicator of hepatocyte damage than ALT.
C. Hemolysis may cause elevated levels.
D. The degree of increase always correlates with the severity of disease.
C. Hemolysis may cause elevated levels.
Stockham and Scott, Ch. 12 Enzymes, pg. 651-652
Which one of the following is the primary mechanism by which serum membrane-associated enzymes may increase ?
a. Increased release by the formation of membrane blebs
b. Increased production because of induced synthesis
c. Increased production because of cell proliferation
d. Increased half-life by the formation of complexes
b. Increased production because of induced synthesis
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology (2nd Ed.), Chapter 12 : Enzymes (p. 644)
Which one of these enzymes is most specific and useful as a marker of hepatocellular damage in horses and cattle in the United States ?
a. Alanine transaminase (ALT)
b. Aspartate transaminase (AST)
c. Iditol dehydrogenase (ID)
d. Lactate dehydrogenase (LD)
c. Iditol dehydrogenase (ID)
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology (2nd Ed.), Chapter 12 : Enzymes (p. 654)
Which of the following regarding ALT is true?
A) The half-life of ALT in the cat is 40-61 hours.
B) Peak ALT concentrations occur in approximately 12hrs.
C) Increased ALT reflects increases in membrane permeability.
D) Hemolysis can be associated with significant increases in ALT.
Answer: C Increased ALT reflects increases in membrane permeability.
(Chapman pg 1213)
Which of the following regarding serum bile acids is true?
A) The predominant bile acid in dogs and cats is cholic acid.
B) Spontaneous gall bladder contraction may result in values outside the reference range.
C) Bile acids are made from cholesterol and 11B-hydroxylase.
D) High fat foods should be given 1hr prior to collecting the Post prandial sample to maximize gall bladder contraction.
A) The predominant bile acid in dogs and cats is cholic acid.
(Chapman pg 1217)
Which of the following is true regarding hepatic dysfunction?
A) γ Globulins are markedly decreased in cases of hepatic dysfunction.
B) Liver dysfunction results in decreased coagulation factors V, VIII and I
C) Increased serum globulins can occur as a result decreased portal filtration.
D) Protein S and C are increased in cases of hepatic dysfunction.
C) Increased serum globulins can occur as a result decreased portal filtration.
(Chapman pg 1219)
How long is the serum half-life of liver-specific ALP in cats?
A. 70 hours B. 1 hour C. 6 hours D. 1 week
C. 6 hours
(pg 1213, “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals” Chapman, SE, Hostutler, RA. VCNA 43, 2013, pp. 1209-1225)
What is NOT a cause of an elevated alkaline phosphatase level in a cat?
A. hepatic lipidosis B. methimazole C. diabetes mellitus D. glucocorticoids
D. glucocorticoids
(pg 1213-1215, “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals” Chapman, SE, Hostutler, RA. VCNA 43, 2013, pp. 1209-1225)
Approximately 80-100% of canine patients with what disease will have an elevated C-ALP?
A. Hyperadrenocorticism B. Hypoadrenocorticism C. Hemangiosarcoma D. Hyperthyroidism
A. Hyperadrenocorticism
pg 657; Stockham and Scott, Fundamentals of Veterinary Clinical Pathology; 2nd Ed.
Alkaline phosphatase could be elevated in each of the following instances in a cat EXCEPT:
A. Hyperthyroidism
B. Pancreatitis
C. Corticosteroid administration
D. Hepatic lipidosis
C. Corticosteroid administration
A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals pg 1215
The average half-life of alanine aminotransferase in cats is:
A. 3.5 hours
B. 24.5 hours
C. 60.5 hours
D. 72.5 hours
A. 3.5 hours
A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals pg 1213
In young, growing dogs under 8 months of age alkaline phosphatase can typically be increased ______ to ______ times the upper reference interval.
A. 2, 3
B. 4, 5
C. 6, 7
D. 8, 9
A. 2, 3
A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals pg 1213
- This hormone promotes bile formation by stimulating HCO3- and Cl- secretion into bile
a. Secretin
b. Gastrin
c. Cholecystokinin
d. Gastric inhibitory peptide
a. Secretin
Reference: Stockham and Scott. Liver Function Page 677
- This term refers to a group of cholesterol derived anionic acids and their dissociated anions
a. Bile Acids
b. Ammonia salts
c. Cholesterol
d. Bilirubin
a. Bile Acids
Reference: Stockham and Scott. Liver Function Page 691
- The pathogenesis of functional cholestasis, or sepsis associated cholestasis, is associated with this cytokine:
a. TNF alpha
b. IL 5
c. IL 10
d. Endothelin 1
a. TNF alpha
Reference: Stockham and Scott. Liver Function Page 688
Which of the following regarding cholestatic disease is true?
A) ALP and GGT are not typically increased until there is marked obstructive icterus in dogs.
B) Functional cholestasis has been reported in dogs associated with E. coli.
C) IL6 results in decreased BA transport proteins to be placed in the hepatocyte membranes resulting decreased bile transport.
D) Bilirubin has a half life of 3 days.
B) Functional cholestasis has been reported in dogs associated with E. coli.
pg 689 Stockham
Which of the following is true regarding serum ammonia concentrations?
A) If stored at room temperature NH4+ will decrease by 2/3 due to degredation.
B) NH4 is produced in the liver by the breakdown of amino acids presented to the liver.
C) Plasma NH4+ is stable up to 4hrs at 4dC and 1-2d at -20C.
D) The dominant analyte is blood ammonia (NH3) compared to ammonium (NH4+)
C) Plasma NH4+ is stable up to 4hrs at 4dC and 1-2d at -20C.
Stockham pg 699
Which of the following is true regarding hyperbilirubinemia.
A) Destruction of heme proteins myoglobin, cytochromes and peroxidases can also result in hyperbilirubinemia
B) Bc and Bu are able to easily distinguish between hemolytic and hepatobiliary icterus.
C) Excess colostrum ingestion by veal calves can lead to perceived hyperbilirubinemia.
D) Fasted horses’ hyperbilirubinemia is due to deficiencies in glucoronide and impaired bile acid conjugation.
A) Destruction of heme proteins myoglobin, cytochromes and peroxidases can also result in hyperbilirubinemia
pg 685 stockham
For which one of these situations may bile acids testing have unreliable results?
a. Administration of lactulose
b. Cirrhosis
c. Hyperbilirubinemia
d. Ileal disease
d. Ileal disease
Chapman SE, Hostutler RA. A laboratory diagnostic approach to hepatobiliary disease in small animals. Vet Clin North Am Small Anim Pract. 2013 Nov;43(6):1209-25. (p. 1217)
When hepatic insufficiency is suspected based on laboratory test results, which one of these conclusions is correct ?
a. It is associated with decreased liver size. b. It indicates that hepatocellular damage is irreversible. c. It may have progressed slowly or rapidly. d. It is consistently associated with increased hepatocellular enzymes activity.
c. It may have progressed slowly or rapidly.
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology (2nd Ed.), Chapter 13: Liver function (p. 679)
Which one of these definitions best describes functional cholestasis ?
a. Defective excretion of bile acids and conjugated bilirubin in the absence of biliary obstruction b. Defective postprandial contraction of the gallbladder caused by poor cholecystokinin response c. Impaired bile flow caused by extrahepatic or intrahepatic obstructive lesions d. Regurgitation of bile acids into sinusoidal blood due to down-regulation of canalicular transport proteins
a. Defective excretion of bile acids and conjugated bilirubin in the absence of biliary obstruction
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology (2nd Ed.), Chapter 13: Liver function (p. 688, 693)
Horses are more prone to hyperbilirubinemia when fasted because,
a. horses primarily conjugate bilirubin with glucose; therefore, a lack of food intake results in a decreased glucose concentration for bilirubin to bind to.
b. horses primarily conjugate bilirubin with lipids; therefore, a lack of food intake results in a decreased lipid concentration for bilirubin to bind to.
c. horses primarily conjugate bilirubin with albumin; therefore, a lack of food intake results in a decreased albumin concentration for bilirubin to bind to.
d. horses do not typically become hyperbilirubinemic.
a. horses primarily conjugate bilirubin with glucose; therefore, a lack of food intake results in a decreased glucose concentration for bilirubin to bind to.
A. Stockham and Scott, Fundamentals of Veterinary Clinical Pathology, 2nd edition, pg. 686
At what rumen pH does the NH3:NH4+ shift towards NH3 and what is the result?
a. pH > 8.0, shifting the NH3:NH4+ towards NH3 results in urea toxicosis and an increased NH4+ plasma concentration.
b. pH < 8.0, shifting the NH3:NH4+ towards NH3 results in urea toxicosis and an increased NH4+ plasma concentration.
c. pH > 6.0, shifting the NH3:NH4+ towards NH3 results in urea toxicosis and an increased NH4+ plasma concentration.
d. pH > 8.0, shifting the NH3:NH4+ towards NH4+ results in urea toxicosis and an increased NH4+ plasma concentration.
a. pH > 8.0, shifting the NH3:NH4+ towards NH3 results in urea toxicosis and an increased NH4+ plasma concentration.
Stockham and Scott, Fundamentals of Veterinary Clinical Pathology, 2nd edition, pg. 701
Which of the following typically causes a greater increase in unconjugated bilirubin compared to conjugated bilirubin?
a. Hepatocellular damage
b. Hemolytic disorders
c. Obstructive cholestasis
d. Functional cholestasis
b. Hemolytic disorders
Source: Stockham and Scott. Fundamentals of Veterinary Clinical Pathology. 2nd ed. Pg. 685
What percentage of hepatocyte dysfunction must be present before biochemical abnormalities are detected?
a. 20-30%
b. 40-50%
c. 50-60%
d. 70-80%
d. 70-80%
Source: “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals.” Chapman, SE and Hostutler, RA. VCNA 43, 2013. Pg. 1219.
Which enzyme is responsible for gallbladder contraction?
a. Gastrin
b. Secretin
c. Cholecystokinin
d. Bradykinin
c. Cholecystokinin
Source: Stockham and Scott. Fundamentals of Veterinary Clinical Pathology. 2nd ed. Pg. 691
Hyperbilirubinemia can be associated with obstructive cholestasis. Which of the following diseases is NOT a common cause of obstructive cholestasis?
A. Blastomycosis
B. Histoplasmosis
C. Diabetes Mellitus
D. Lymphoma
A. Blastomycosis
Stockham and Scott, Fundamentals of Clinical Pathology, pg 684
Handling of collected blood samples is important. Ultraviolet light is reported to cause degradation of bilirubin. According to Stockham and Scott direct exposure to sunglight may cause a ______ decrease within ______.
A. 50%, 1 hour
B. 50%, 6 hours
C. 50%, 12 hours
D. 50%, 24 hours
A. 50%, 1 hour
Stockham and Scott, Fundamentals of Clinical Pathology, pg 683
Dysfunction of the liver can be expected when what percentage of the liver mass is decreased?
A. 40-50%
B. 50-60%
C. 60-70%
D. 70-80%
D. 70-80%
Stockham and Scott, Fundamentals of Clinical Pathology, pg 680
Which one of these abnormalities on a CBC and chemistry would be most suspicious for decreased hepatic functional mass?
a) Anemia, microcytosis, lipemia, hypobilirubinemia
b) Codocytosis, hypoalbuminemia, hypocholesterolemia
c) Acanthocytosis, hyperglycemia, increased liver enzymes
d) Hyperbilirubinemia, hypercholesterolemia, increased ALP
b) Codocytosis, hypoalbuminemia, hypocholesterolemia
Page 678. a) hyperbilirubinemia would be expected from hepatic insufficiency from decreased ability to excrete bilirubin c) acanthocytosis is characteristic of HAS or a lipid metabolic defect, hypoglycemia would be expected from hepatic insufficiency D) this is characteristic of cholestasis
Source: Stockham, S.L. and M.A. Scott, Fundamentals of veterinary clinical pathology. 2nd ed2008, Ames, Iowa: Blackwell Pub
Fasting hyperbilirubinemia in horses is partly due to?
a) Functional cholestasis
b) Obstructive cholestasis from hepatic lipidosis
c) Increased plasma fatty acids from lipolysis
d) Increased glucose/glucuronide conjugation
c) Increased plasma fatty acids from lipolysis
Page 686. c) fatty acids compete with Bc for update by Y-protein and Z-protein on the surface of hepatocytes D) horses are more susceptible because they use more glucose than other species to conjugate Bu and thus they have decrease ability to conjugate Bu when fasting
Source: Stockham, S.L. and M.A. Scott, Fundamentals of veterinary clinical pathology. 2nd ed2008, Ames, Iowa: Blackwell Pub
In cholestasis how is excess Bc handled in the body?
a) Excreted in the urine as Bc
b) Spills over into the systemic circulation and becomes covalently bound to albumin forming Bα
c) Increased rate of transport into the bile canaliculi
d) Increased rate of production in the intestine to urobilinogen
a) Excreted in the urine as Bc
Page 688. b) Bδ c) in cholestasis there is decreased rate of transport into the bile canaliculi d) since there is a decreased rate of transport to the bile there is a decreased rate of Ub production
Source: Stockham, S.L. and M.A. Scott, Fundamentals of veterinary clinical pathology. 2nd ed2008, Ames, Iowa: Blackwell Pub
Which one of the following statements is TRUE regarding bile acids (BA) in small animals?
A. Cytokines such as TNF-alpha often cause an increase in bile acid transport, resulting in lower levels of serum BA.
B. Healthy animals with normal liver function should not have an increase in serum BA following a meal.
C. Accumulation of BA in the liver can lead to hepatocellular damage.
D. Congenital portosystemic shunts cause an increase in serum BA, but acquired shunts do not.
C. Accumulation of BA in the liver can lead to hepatocellular damage.
Stockam and Scott, Ch. 13 Liver Function, pg. 692-693
Which one of the following statements is TRUE regarding bilirubin?
A. A large amount of bilirubin is globulin-bound.
B. It is normal to see small amounts (1+ or 2+) of bilirubin in feline urine.
C. A normal serum total bilirubin completely rules out hemolytic disorders.
D. Due to its long half-life, hyperbilirubinemia may persist for days even after correcting the underlying cause.
D. Due to its long half-life, hyperbilirubinemia may persist for days even after correcting the underlying cause.
Stockam and Scott, Ch. 13 Liver Function, pg. 681-684
Which one of the following statements is TRUE regarding ammonium?
A. Most ammonium is produced in muscle fibers.
B. Congenital diseases affecting the urea cycle may lead to hyperammonemia.
C. Hyperammonemia can result from portosystemic shunts, but not from hepatocellular disease.
D. Strenuous exercise can cause a decrease in plasma ammonium levels due to large amounts of ATP production.
B. Congenital diseases affecting the urea cycle may lead to hyperammonemia.
Stockam and Scott, Ch. 13 Liver Function, pg. 698-701
Bile acids are primarily synthesized in the liver from what?
A. Vitamin K B. sucrose C. cholesterol D. glucose
C. cholesterol
(pg 1217, “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals” Chapman, SE, Hostutler, RA. VCNA 43, 2013, pp. 1209-1225)
Ammonia is produced primarily as a byproduct of colonic bacteria digestion of what?
A. water B. lipids C. dietary carbohydrates D. dietary protein
D. dietary protein
(pg 1218, “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals” Chapman, SE, Hostutler, RA. VCNA 43, 2013, pp. 1209-1225)
Which of the following is NOT a cause of increased ammonia levels?
A. administration of lactulose B. high-protein meals C. hepatic insufficiency D. excessive exercise
A. administration of lactulose
(pg 1219, “A Laboratory Diagnostic Approach to Hepatobiliary Disease in Small Animals” Chapman, SE, Hostutler, RA. VCNA 43, 2013, pp. 1209-1225)
Bu (unconjugated bilirubin) is often greater than Bc (conjugated bilirubin):
a. In an anorexic horse
b. In a cow with hemolysis associated with Anaplasma marginale infection
c. In a dog with sepsis due to Staphylococcal pneumonia
d. Both a & b
e. All of the above
d. Both a & b
Stockham, S. L., Scott, M. A. (2008), Fundamentals of Veterinary Clinical Pathology. 2nd ed. Ames, Iowa: Blackwell Publishing, pg. 685
Which of the following inflammatory cytokines interferes with a hepatocyte’s ability to excrete conjugated bilirubin:
a. IL-1
b. IL-10
c. TNF-α
d. TNF-β
c. TNF-α
Stockham, S. L., Scott, M. A. (2008), Fundamentals of Veterinary Clinical Pathology. 2nd ed. Ames, Iowa: Blackwell Publishing, pg. 688
High NH4+ concentrations can result in an increase in lactate:
a. Via interference with the Krebs Cycle and an increase in ATP causing a shift towards anaerobic glycolysis.
b. By directly stimulating myocyte activity and increasing anaerobic glycolysis, similar to strenuous exercise.
c. By antagonizing insulin, thereby reducing the ability of glucose to be transported into the cell.
d. All of the above
a. Via interference with the Krebs Cycle and an increase in ATP causing a shift towards anaerobic glycolysis.
Stockham, S. L., Scott, M. A. (2008), Fundamentals of Veterinary Clinical Pathology. 2nd ed. Ames, Iowa: Blackwell Publishing, pg. 542
All of the following metabolic diseases can cause decreased hepatic functional mass except:
A) Hepatic lipidosis B) Hypoadrenocorticism C) Hyperadrenocorticism D) Diabetes mellitus
B) Hypoadrenocorticism
Source: Stockham and Scott, p. 690
This is the main cytokine that has been implicated in decreasing bile acid transport proteins in hepatocyte canalicular membranes, leading to a functional (sepsis-associated) cholestasis.
A) TNF-a B) IL-10 C) IL-1 D) TGF-B
A) TNF-a
Source: Stockham and Scott, p. 698
All of the following are true regarding testing for ammonium concentration except:
A) Hemolysis causes false decreases of NH4+ in some assays. B) In dogs with liver disease, arterial samples have greater NH4+ than venous samples. C) The sample is considered to be stable for up to 4 hours at 4 degrees Celsius. D) Within hours of storage at room temperature, the NH4+ concentration will be up to 2-3 times its starting value.
A) Hemolysis causes false decreases of NH4+ in some assays.
The heme pigment interferes with light transmittance and erythrocytes contain NH4+, causing a false increase in the value.
Source: Stockham and Scott, p. 709
