Term
| Does liver disease cause an elevation or fall in liver enzymes? What about liver failure? |
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Definition
-disease = elevation in enzymes
-failure = failure to synthesize and/or failure to clear |
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Term
| Does hepatocyte injury cause increase in leakage or induced enzymes? What about cholestasis? |
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Definition
-hepatocyte injury = leakage
=cholestasis = induced |
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Term
| True or False: Liver enzymes DO NOT give information about liver function! |
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Definition
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Term
| Liver failure does not occur until loss of ___-___% functional mass. |
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Definition
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Term
| Is ALT liver or muscle specific? |
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Definition
| -livr specific except severe muscle injury |
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Term
| What kinds of drugs cause mild increases ALT in dogs? |
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Definition
-steroids, anticonvulsants
-typically mild increases (2-5X URL) |
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Term
| Is SDH liver or muscle specific? |
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Definition
|
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Term
| Does SDH have a short or long half life? |
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Definition
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Term
| In what animals is SDH useful? |
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Definition
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Term
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Definition
-highly sensitive in dogs
-cholestasis, drug induction (dogs: steroids and anticonvulsants), osteoblastic activity (young animals), neoplasia, colostrum |
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Term
| What are the 3 isoforms of ALP? |
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Definition
-LALP (liver)
-BALP (bone)
-CALP (corticosteroid induced) |
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Term
| In what species is GGT useful? |
|
Definition
-Dogs and Cats: inc parallel ALP
-Horses and Ruminants: better than ALP |
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Term
|
Definition
-cholestasis
-drug induction in dogs: glucocorticoids, anticonvulsants
-neonates: bovine, ovine, canine, foals |
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Term
| What do enzymes indicate? What do they not tell us? |
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Definition
-Indicate: site of tissue injury, damage or cholestasis (if r/o drug induction)
-don't tell us: type of hepatic injury, prognosis, about hepatic function |
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Term
| How does the significance of rises in ALP change in a dog vs a cat? |
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Definition
-cat's liver has much less ALP thus mild increases (2-3X) are significant
-cats also do not have drug induction but hyperthyroidism can cause an increase |
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Term
| GGT is usually more sensitive than ALP in cats. What is the only exception? |
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Definition
| -hepatic lipidosis (high ALP with normal GGT) |
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Term
| Icterus is visible when total bilirubin > ___ mg/dL. |
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Definition
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Term
| What is the major cause of pre-hepatic hyperbilirubinemia? |
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Definition
| -increased erythrocyte destruction |
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Term
| What is the physiologic process behind hepatic hyperbilirubinemia? Possible causes? |
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Definition
-decrreased uptake and/or conjugation
-Possible causes: dec functional mass, fasting (horses) |
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Term
| How do you treat fasting hyperbilirubinemia in horses? What is the mechanism? |
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Definition
-resolves within 48 hrs of refeeding
-mech: mobilized FAs compete for carrier proteins |
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Term
| What are the possible causes of hyperbilirubinemia due to disruption of bile flow (hepatic or post-hepatic)? |
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Definition
-biliary system: inflammation, neoplasia, calculi
-hepatocyte swelling
-intestinal/pancreatic mass effect
-bile leakage into abdomen
-sepsis (functional cholestasis) |
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Term
| In small animals most is (conjugated/unconjugated) billirubin. In large animals, most is (conjugated/unconjugated) billirubin. |
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Definition
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Term
| Do dogs have low or high renal threshold for bilirubin? |
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Definition
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Term
| Total bilirubin is (consistantly/inconsistantly) increased with liver dz in ruminants. |
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Definition
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Term
| Why do we check the PCV in regards to total bilirubin in ruminants? Why do we ask about fasting state? |
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Definition
-total bilirubin is commonly increased with hemolysis
-because fasting/rumen stasis can cause mild increases in total bilirubin |
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Term
| What is the purpose of bile acids? |
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Definition
| -emulsify fats for the absorption of fat and fat-soluble vitamins |
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Term
| What are the 3 most common reasons for increased bile acids? |
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Definition
-portosystemic shunt: congenital or from cirrhosis (no first-pass clearing of bile acids)
-decreased heatocyte bile acid uptake (liver dz and failure)
-dec bile acid excretion with subsequent regurgitation (cholestasis and leakage from bile duct or gall bladder) |
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Term
| True or False: If bilirubin is increased due to cholestasis, bile acids will also be increased. |
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Definition
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|
Term
| Is total bilirubin or bile acids more sensitive fore evaluating hepatic function? |
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Definition
|
|
Term
| How does bile acid testing differ b/n dog, cat, and horse? |
|
Definition
-same in dog and cat
-no gall bladder in a horse so no post sample |
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Term
| nWhere is blood ammonia generated? Where is it cleared? |
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Definition
-generated in GI tract
-cleared by liver |
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Term
| When are blood ammonia levels increased? |
|
Definition
-portosystemic shunt
-loss of >60% hepatic function |
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|
Term
| Are bile acids or blood ammonia levels more sensitive? |
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Definition
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Term
| What is liver failure? It results in a decrease in what? |
|
Definition
-loss of 60-80% of hepatic function
-dec in albumin, urea (BUN), glucose, cholesterol, and coagulation factors |
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Term
| What happens to PT and APTT in the case of liver failure? Why? |
|
Definition
-both prolonged
-due to decreased factory synthesis |
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|
Term
| Can PT and APTT be prolonged with severe cholestasis? |
|
Definition
-yes
-due to blockage of bile flow => reduced vitamin K absorption => inactive Vitamin K dependent factors |
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