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Year 4 > Equine Liver > Flashcards

Flashcards in Equine Liver Deck (31)
1

What is jaundice?

Retention of bilirubin
Unconjugated form is more prominent in horses

2

What disease can mask jaundice and why?

Sepsis, as the mm are deep red/blue

3

Give some clinical signs of liver disease

Jaundice
Weight loss
Depression/CNS signs
Photosensitisation (accumulation of phylloerythrin from chlorophyl)
Haemorrhage
Colic
Oedema (due to hypoalbuminaemia, rare)
Diarrhoea
Dyspnoea (usually Ragwort; laryngeal paralysis)
Anorexia/inappetence

4

How would you diagnose liver disease?

Liver enzymes
Serum bilirubin
Liver function tests (bile acids)
Blood ammonia (hyperammonaemia)

5

Give the functions of the liver

Digestive and secretory (bile salts)
Metabolic (CHO, protein, fat metabolism)
Detoxification/excretory
Synthetic (clotting factors, proteins)
Storage (vitamins, minerals)

6

Elevated GGT would indicate disease where?

Mainly biliary tract
Also specific to liver and pancreas

7

Elevated AST indicates what?

Hepatocellular damage

8

Elevated SDH indicates what?

Hepatocellular damage

9

What is the best test for liver function?

Bile acids
Continuous production so no need to fast
Correlated with severity

10

High blood ammonia levels may then cause what?

Encephalopathy (decline in brain function)

11

Which clotting factor has the shortest half life so is the first to have a prolonged PT (prothrombin time) when testing liver function?

VII

12

Give some risks of performing a liver biopsy

Haemorrhage (don't do if clinical coagulopathy)
Inappropriate sample eg focal lesions
Negative culture
Infections
Pneumothorax (rare)

13

Give some advantages of performing a liver biopsy

Biopsy score is the best indicator of prognosis in liver disease
(>6= poor prognosis)

14

Give some clinical signs of ragwort poisoning

Frequently only see signs of liver failure just prior to death
Early clinical signs are hard to difficult to detect and non-specific:
weight loss, behavioural change, anorexia
Other signs: inspiratory dyspnoea (laryngeal paralysis), severe CNS signs (hepatic encephalopathy), colic (gastric impaction), photosensitisation, haemorrhages, icterus

15

How do you diagnose ragwort poisoning?

History
Clinical presentation
Clinical pathology (GGT best enzyme to screen)
US (small liver may be difficult to find)
Biopsy (may not always see megalocytosis)

16

How do you treat ragwort poisoning?

Probably shouldn't treat if bile acids >50 umol/L (>20=poor prognosis)
Can try supportive therapy (fluids, electrolytes, glucose)
Reduce hepatic encephalopathy (moderate to low protein diet, high branched chain amino acids -BCAAs, neomycin or metronidazole)

17

What causes cholangiohepatitis and cholelithiasis?

Ascending bile duct infection form GIT
Gram-negatives deconjugate bilirubin -> precipitates out and causes choleliths

18

Give the clinical signs of cholangiohepatitis and cholelithiasis

Fever, jaundice, colic
Marked increase in liver enzymes esp GGT
Biopsy may yield a positive culture (neutrophilic inflammation)

19

How would you treat cholangiohepatitis and cholelithiasis?

Long-term antibiotic therapy

20

What is chronic active hepatitis?

Any progressive inflammatory hepatitis
Biopsy may indicate immune-mediated (plasmocytic-lymphocytic)

21

How should you treat chronic active hepatitis?

Corticosteroids or other immunosuppressive medications eg azathioprine

22

Give the clinical signs of acute hepatitis

Severe CNS signs, jaundice, discoloured urine

23

Give some risk factors for hyperlipaemia

Breed
Obesity
Females
Age vs insulin sensitivity (older)
Underlying disease
Transport, stress, lactation
Starvation

24

Describe the pathogenesis of hyperlipaemia

Breakdown of stored fat (hormone-sensitive lipase) -> fatty acids to liver -> energy
Liver has poor ketogenic capability -> energy production is overwhelmed -> trigylcerides accumulate in liver and in plasma -> hyperlipaemia -> liver failure -> death
Ideally want to promote re-uptake in periphery by LPL (lipoprotein lipase) but LPL can't keep up with HSL and liver

25

Give some presenting signs of hyperlipaemia

Non-specific: anorexia, weakness, lethargy, progress to more severe CNS and other signs
Signs may be due to hyperlipaemia, underlying disease, or secondary liver disease
Be aware of at risk animals eg colic surgery

26

How do you diagnose hyperlipaemia?

Cloudy serum
-Triglycerides >5 mmol/L = hyperlipaemia
-Triglycerides <5 (but over 1.5) = hyperlipidaemia
Presence of liver disease, azotaemia (inhibits LPL-lipprotein lipase)

27

How do you treat hyperlipaemia?

Treat underlying disease and parasites
Positive energy balance
Correct dehydration, electrolyte imbalance, acidosis
Other symptomatic therapy
Normalisation of lipid metabolism
-Insulin therapy? Risk of laminitis. Don't give unless you have to.

28

What is the prognosis like for hyperlipaemia?

Guarded to poor
Worse if female, other organ involvement, poor initial response, failure to eat
Get horse out of the box

29

Give 2 causes of jaundice

Anorexia (causes hyperbilirubinaemia)
Haemolysis

29

How do you distinguish between the liver and spleen on ultrasound?

Spleen is more hyperechoic (brighter/more white) than liver

30

What should you do before taking a liver biopsy?

Check clotting profile