Liver: case studies Flashcards Preview

Digestive System > Liver: case studies > Flashcards

Flashcards in Liver: case studies Deck (31):
1

Cholestatic enzymes

GGT (gamma-glutamyl transferase) and ALP (alkaline phosphatase)

This often indicate a mass or biliary obstruction

2

Inflammation enzymes

ALT (alkaline-transferase) and AST (aspartate-transferase)

3

What causes jaundice?

Elevated bilirubin. causes yellow sclera and skin.
Due to a biliary obstruction (bile release), or hepatocellular injury (lysis)

Haemolysis also causes bilirubin

4

What measure the livers synthetic function

Prothrombin Ratio (clotting factors)
Albumin

5

What measure the livers detox function

NH3 ammonia levels, if not detoxified they can build up in the brain > hepatic encephalopathy

6

If the AST and ALT are really high, what is the much common cause to look at first?

Viral infection, most commonly Hep A, B, C

7

Why should you be worried about blood transfusions pre 90's

Because there wan't the regulations there are now, so potentially carrier of infection. eg) hep B and C

8

Chronic Hepatitis A

Doesn't exist, Hep A is benign and self-limiting

9

How do you determine if viral hepatitis is acute of chronic

Acute: first 6 months
Chronic: post 6 months

10

Causes of Hep B and Hep C, how are they transmitted, what do they cause and available treatment?

Causes of Hep B:
*** sexually transmitted
drug use
mother to child
horizontal transmission

Causes of Hep C
***Drug use
blood transfusion
low sexual transmission risk
mother to child
occupational
tattoo

Both transmittable through blood

Can lead to cirrhosis and hepatocellular carcinoma (if aqquired later some Hep B patients will resolve)

There is a vaccine for Hep B but not Hep C (incurable)

11

Interferon

Old drug for HCV, many adverse side -effects, low success rate (50%), a cytokine so gives flu like effect.
-given as a sub-cutaneous injection
Initially alone
the interferon + ribavirin

12

Breakthrough HCV treatment

Direct-acting Antiviral agents
-tablets
- Cure rates >90%
Been the cause of declining need for liver transplants

13

Oesophageal/ gastric Varices

Due to pressure increase due to portal hypertension (associated with cirrhosis), these are dangerous as they have potential to bleed.

Treatments: 'Banding', suck varices up into a cap, rubber band strangles varices and stops the bleeding

This may need to be done several times, but they can REFORM, so it's only temporary!

14

Portal circulation consists of?

Portal Vein: that drains nutrient rich blood from the GI tract and spleen to the liver
venous blood passes through the
Liver > IVC > heart

15

Portal Hypertension

High pressure in the portal vein, more resistance making it harder for blood in the portal circulation to return to the heart.
Portosystemic shunts/collaterals form, that enlarge and try to divert blood away from the portal system to the heart > varices

16

Two most common place to get varices

1) Gastro-oesophageal Junction: work upwards
2) Stomach: particularly fundus

17

Normal Portal BF vs Cirrhosis (Portal hypertension)

BP: 55mmHg
Supplies 3/4 Blood flow to liver (70% O2)
100% blood > hepatic vein > systemic circulation

BP: 12mmHg
portosystemic shunts formed > varices

18

Liver intitially ______ then progressively ______

Liver intitially elarged then progressively shrinks

19

Is fibrosis reversible?

Potentially if the liver is allowed time to regenerate by removing inflammatory cause. If this doesn't occur >> cirrhosis 'irreversible scarring'

20

What causes fibrosis

repeated bouts of inflammation

21

Can the liver function with cirrhosis?

When it is mild, as the liver is good at compensating, huge reserve capacity. However as it progresses more and more function is lost (liver failure at 80-90%)

22

Hepatic Encephalopathy. Early and late symptoms

Build up of NH3 toxins in the brain due to liver failure. THe liver is unable to detoxify substances from the bacterial metabolism. Also portosystemic shunts bypass the liver entirely (no detox at all). You get a build up of ammonia in the blood (passes blood-brain barrier)

Early Symptoms: mood and personality change. Inverted sleep pattern. (hard to diagnose)

Late Symptoms; Confusion and bizarre behaviour, drowsiness and coma.

23

Treatment of HE

Lactulose
-normally a laxative to treat constipation
-decrease ammonia production by bacteria
-makes it a non-absorbable substance > excreted

For management but not definitive treatment.

24

Ascites

fluid accumulation in the peritoneum > abdominal distention.
Often caused by portal hypertension
-Elevated hydrostatic pressure in PV > fluid moves out of circulation
-Low oncotic pressure in PV (low serum albumin) unable to hold onto fluid

25

Hypersplenism

1) Splenomegaly : swollen spleen
2) Low platelet count: platelets going through spleen are destroyed at a higher rate

26

People can donate upto _____% of their liver

50%

27

Definitive treatment for liver failure

Liver transplant

28

Acute thrombosis of Hepatic veins

Budd-Chiari
-outflow of blood from liver obstructed
- liver becomes congested > hepatocellular damage
-Results in PH with ascites forming

29

Fulminant

very severe and sudden

30

Causes of Budd-Chiari

75% no obvious cause
25% cause identifies
-tumor
-pregnancy
-Contraceptive pill
-clotting disorders

31

Management of Budd-Chiari

Portocaval shunting to divert blood flow
-TIPSS (transjugular intrahepatic portosystemic shunt): reduces resistence of BF to liver, done for PH
-surgical

Anticoagulation : thin blood and dissolve clot

Diuretics