Icterus and hepatic encephalopathy in small animals Flashcards Preview

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Flashcards in Icterus and hepatic encephalopathy in small animals Deck (23):
1

icterus - define

hyperbilirubinaemia

2

bilirubin in the liver

conjugated with glucuronic acid - water soluble for excretion in the urine

3

pre-hepatic icterus - cause

Haemolysis
Conjugation + uptake of bilirubin into liver overwhelmed

4

hepatic icterus - cause

Uptake, conjugation and excretion of bilirubin in hepatocytes overwhelmed

5

post-hepatic icterus - cause

Cholestasis
Conjugation, excretion and uptake back into liver overwhelmed

6

clinical signs linked with gastrointestinal tract

Vomiting
Diarrhoea
Acholic faeces
Melaena
Abdominal effusion = ascites (cirrhosis)

7

clinical signs linked with neurological system

Personality change
Ptyalism (cats) (hypersalivation)
Head pressing
Disorientation
Seizures
stupor

8

clinical signs linked with renal/urinary system

PU/PD
Pollakiuria, stranguria, dysuria
Bilirubinuria

9

haematological signs

Pale mucous membranes - Anaemia from GI haemorrhage, anaemia of chronic disease, coagulation disorder, haemolysis

10

DDx for pre-hepatic

Immune Haemolytic Anaemia
Babesia infection
Toxins: Onions, lead, copper

11

DDx for hepatic - cat

Suppurative Cholangiohepatitis
Lymphocytic plasmacytic hepatitis
Hepatic Lipidosis
Feline Infectious Peritonitis
Toxins (acetaminophen, aspirin)
Neoplasia

12

DDx for hepatic - dog

Acute liver disease (toxins)
Leptospirosis
Chronic hepatitis
Neoplasia

13

DDx for post-hepatic

Pancreatitis
Neoplasia (Liver, duodenum, pancreas)
Cholelithiasis

14

How would you differentiate between prehepatic and hepatic icterus?

Perform PCV/TS
If prehepatic: PCV low, TS normal
If hepatic: usually PCV normal, TS can be low if Albumin low

15

How would you differentiate between hepatic and posthepatic icterus?

Ultrasound will identify obstruction of the gall bladder and masses or pancreatitis associated with it

16

full hepatic disease workup

Haematology, chemistry profile, UA
Abdominal ultrasound
Liver function tests
Coagulation tests
Aspirate effusion, cytology
Liver fine needle aspirate
Fine needle aspirate and culture of bile
Liver biopsy: Histology, culture

17

liver enzymes

ALT: most liver specific enzyme
AST: also present in muscle, intestines…
AP: Biliary duct cells, Isoenzymes: Cortisol-induced (only dogs!), bone, intestines, liver, placenta etc

18

indications for liver failure on chemistry profile

Low albumin
Low cholesterol
Low glucose
Low BUN (blood urea nitrogen)

19

measuring bile acid level

first measurement fasted
feed then take second measurement:
rate limiting step = re-uptake of bile acids from the blood into hepatocytes
elevated in liver failure/portosystemic shunt

20

hepatic encephalopathy

Digestion of proteins: NH3 und aromatic AA go directly into the blood without passing through the liver first
Exposure of CNS to shunted gut-derived toxins

21

hepatic encephalopathy - clinical signs

Neurologic signs
bizarre behaviour
head pressing
Seizures
intermittent blindness
Cats: Ptyalism
urate stone formation

22

Most important diseases causing HE in small animals - cats

Acute liver failure (toxic)
Hepatic lipidosis
Neoplasia
Portosystemic shunts

23

Most important diseases causing HE in small animals - dogs

Portosystemic shunts
Liver failure (acute): Toxic, infectious
Liver failure (chronic): cirrhosis