Icterus and liver / pancreas disease Flashcards Preview

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Flashcards in Icterus and liver / pancreas disease Deck (31):

pancreas enzyme specificity?

amylase and lipase arent very specific

can use CPLI (canine pancreatic lipase) which is specific


What hepatocellular enzymes are used to measure damage to hepatocytes?

ALT - most specific in cats and dogs, can be released from massively damaged muscle
AST - also in muscle and RBC
SDH - used in horse


What can you measure to rule out muscle involvement?

Creatinine kinase - increases and decreases faster than ALT and AST


What enzymes are used to measure cholestasis?

ALP - from bile duct ep and increases with cholestasis, there is a steroid induced isoform in dogs, very short half life in cats

GGT - from bile duct ep, used in large animals


How would you expect the measure of hepatic function to change with liver failure?

high bilirubin
low urea
high ammonia
low glucose
low albumin
altered cholesterol


What are the 6 main things measured to test hepatic function?

bilirubin - check conjugated vs unconjugated

ammonia and urea
cholesterol - increase with cholestasis and decrease with hepatic failure
bile acids (no gall bladder in horses)
ammonium - hard to measure


How is icterus categorised?

pre-hepatic, hepatic and post hepatic


What is pre-hepatic icterus?

increased bilirubin production - haemolysis

mainly unconjugated bilirubin


What are the main causes of pre-hepatic icterus in horses?

neonatal isoerythrolysis, EIA, autoimmune haemolytic anaemia


What is hepatic icterus?

impaired hepatic uptake or conjugation of bilirubin

increased unconjugated than normal


Main causes of hepatic icterus in horses?

(hepatocellular disease,) anorexia


What is post-hepatic icterus?

impaired excretion of bilirubin

more conjugated


Main causes of post - hepatic icterus in horses?

cholangitis, cholangiohepatitis


Main ddx for horse icterus?

1) anorexia
2) anaemia
3) liver disease


Horse clinical signs of liver disease?

colic (mild)
weight loss

photosensitization, diarrhoea, bilateral laryngeal paralysis, haemorrhagic diathesis, ascites, dependent oedema


What is hepatic encephalopathy?

severe hepatic dysfunction causing clinical signs of cerebral disease

can be due to reduced ammonia clearance so toxic ammonia gets to brain

cat causes: acute liver failurs, hepatic lipidosis, neoplasia
dog causes: portosystemic shunt, liver failure


Main diagnostics for hepatic disease in horses?

bile acids

hepatic biopsy


Treatment of hepatic disease in horses?


HE - sedate and hypertonic saline for cerebral oedema

Dietary - high carb., limited protein


What is pyrrolizidine alkaloid toxicity in horses?

Ragwort poisoning
cumulative over 4 - 12 weeks
PA is normally metabolised by the liver to toxic pyrrole derivatives which are anti-mitotic to see megalocytes on biopsy

poor prognosis


What is Theillers disease in horses?

unknown cause
widespread hepatic necrosis and a small liver


What is Tyzzer's disease in horses and what is it caused by?

Clostridium piliformis
in 7-42 day old foals
found dead
multifocal hepatitis and enteritis


What can cause and how to diagnose and prognosis of cholelithiasis in horses?

Cause: parasites, ascending biliary inf, biliary stasis
Diagnose: fever + icterus + colic , lliver enzymes, ultrasounds, biopsy and histopath.
Prognosis: depends on degree of fibrosis


What is hyperlipaemia in horses?

- mainly seen in obeses shetlands/ ponies
- due to a negative energy balance recruiting fat stores so triglycerides (TG) are made in the liver and as they are obese there is so much fat broken down that the TG cant be taken up by peripheral tissues so stays in the liver
- measure TG in serum
- treat: reverse NEB, support hepatic disease, eliminate stress, inhibit further fat metabolism (insulin) , try and increase TG uptake by peripheral tissues
- poor prognosis


DDX for pre-hepatic icterus in small animals?

immune mediated haemolytic anaemia, babesia,toxins


DDX for hepatic icterus in cat and dog?

cat - suppurative (neutrophilic) / non suppurative (lymphocytic) cholangiohepatitis, lymphocytic plasmocytic hepatitis, hepatic lipidosis, FIP, toxins, neoplasia

dog - acute liver disease, leptospirosis, chronic hepatitis, neoplasia


DDX for post- hepatic icterus in small animals?

pancreatitis , neoplasia, cholelithiasis, pancreatic disease ( neoplasia, abscess) , bile duct rupture


How do you differentiate between pre / hepatic/ post icterus?

pre vs hepatic : blood (PCV)

hepatic vs post : abd rads / ultrasound - blockages
Cat-, serum albumin as if hypoalbuminaemia then likely hepatic but normal doesn't help


Small animal clinicalCats signs of icterus?

-GI : vom, dia, acholic faeces, melaena, ascites
-neurologic: personality change, ptyalism (drooling cats) , head pressing, disorientation, seizures, stupor
-Renal / urinary: PU/PD , pollakiuria, stranguria, dysuria, bilirubinuria
-Haematologic : pale MM


How does the bile acid function test work?

test fasted levels then feed
should normally increase then decrease in blood
if remains increased then impaired uptake back into liver


What is hepatic lipidosis in cats?

Cats normally live on a protein only diet so if theyre anorexic then FA are released from adipose tissue and go to the liver. Normally they are b-oxidised and made into energy and low density lipoproteins but when liver isnt working they accumulate


Outline normal bilirubin metabolism

from old RBC , unconjugated but bound to albumin in the blood - liver - conjugated to glucronic acid and unbound from albumin - now water soluble - liver