Liver disease

Question 1

where is the liver in the abdonmen?

Answer 1

upper right quadrant (left hypochondriac)

Question 2

what are the functions of the liver?

6

Answer 2

1. digestion (produces bile)
2. storage (glycogen, copper, iron, vitamins A,B12, D, E, K)
3. synthetic (coagulation factors, albumin, thrombopoeitin, IGF-1)
4. breakdown (drugs, alcohol, toxins, ammonia, bilirubin)
5. immune (filtration of blood, kupffer cells)
6. metabolism (carbohydrate, protein, lipids)

Question 3

what is the blood supply to the liver?

2

Answer 3

• hepatic artery (25%)
• hepatic portal vein (75% from GI tract)

Question 4

where does the blood from the liver drain to?

Answer 4

hepatic vein

Question 5

describe the structure of the liver

Answer 5

• arranged into lobules (functional unuits)
• portal triad (arteriole, venule, bile duct) (6)
• central vein in centre of lobule

Question 6

what are the main cells called in the liver lobules?

Answer 6

hepatocytes

Question 7

what is the portal triad in the liver comprised of?

3

Answer 7

• arteriole from hepatic artery
• venule from hepatic portal vein
• bile duct leaving liver to bile duct

Question 8

what are the functional units of the liver called?

Answer 8

lobules

Question 9

how does liver disease occur?

Answer 9

damage to the hepatocytes

Question 10

what is liver failure?

Answer 10

the loss of important functions of the liver

Question 11

what can cause acute liver failure?

2

Answer 11

• paracetamol overdose
• viral hepatitis (A,B,E)

Question 12

what can cause chronic liver failure?

4

Answer 12

• alcohol
• viral hepatitis (B,C)
• non-alcohol fatty liver disease (NAFLD)
• other - haemochromatosis, autoimmune hepatitis, Wilson’s disease, cystic fibrosis

Question 13

what are some signs and symptoms of liver disease?

10

Answer 13

• cachexia - wasting of body and muscles due to impaired metabolic funciton
• encephalopathy - brain disturbance due to build up of ammonia
• jaundice - build up of bilirubin
• excoriations - scratches on skin due to itching
• coagulopathy - easy bleeded due to loss of TPO and coagulation factors
• bruising - due to easy bleeding
• ascites - fluid in abdomen due to reduced albumin production = decreased oncotic pressure
• peripheral oedema - fluid in legs due to reduced albumin production = decreased oncotic pressure
• palmar erythema - red palms due to elevated oestrogen levels
• gynaecomastia - development of breast tissue in males (increased oestrogen levels)

Question 14

how do you manage acute liver failure?

4

Answer 14

• critical care (very unwell)
• supportive measures and invavsive monitoring (Iv fluids, IV glucose, vitamin K, blood products)
• NAC (N-acetylcystein) if paracetamol overdose (prevents hepatocyte necrosis)
• liver transplant - early consideration

Question 15

what is the maximum dose of paracetamol you can take in 24 hours if adult body weight >50kg?

Answer 15

4000mg = 8 500mg tablets (2 tablets every 4-6 hours)

Question 16

what is the maximum dose of paracetamol you can take in 24 hours if adult body weight <50kg?

Answer 16

2000mg = 4 500mg tablets (1 tablet every 4-6 hours)

Question 17

what is the product of broken down paracetamol, what can it cause and what drug can prevent it?

2

Answer 17

NAPQI
* causes hepatocyte necrosis (NAC prevents this)

Question 18

what are the symptoms of paracetamol overdose after 24 hours, 2-3 days and 3-4 days?

Answer 18

• 24 hours: nausea and vomiting
• 2-3 days: right upper abdominal pain, recurrence of nausea and vomiting
• 3-4 days: signs of acute liver failure

Question 19

what is cirrhosis?

Answer 19

end stage chronic liver failure
* chronic inflammation and damage to liver cells
* damaged cells are replaced with scar tissue (fibrosis)

Question 20

what are the stages of chronic liver disease?

5

Answer 20

1. healthy
2. staetosis inflammation
3. fibrosis
4. cirrhosis
5. HCC (HepatoCellular Carcinoma)

Question 21

until what stage of chronic liver disease can the liver repair itself?

Answer 21

until fibrosis of the liver

Question 22

what do you use to measure the severity of chronic liver disease? what are the different classes?

Answer 22

Child’s-Pugh classification
* A, B, C (C is most severe)

Question 23

what does fibrosis of the liver lead to?

Answer 23

• increased resistance to the hepatic portal vein blood blow
• results in back pressure of blood in the portal system - portal hypertension
• causes varices (swollen blood vessels) - often at lower part of oesophagus
• high risk of vessel bursting = variceal bleed

Question 24

what are the stages of alcohol related liver disease?

3

Answer 24

1. alcohol fatty liver
2. alcohol hepatitis
3. cirrhosis

Question 25

what are the dental implications of alcohol? | 6

Answer 25

* oral cancer * tooth erosion (NCTSL - non-carious tooth surface loss) * staining * trauma risk * caries * oral hygiene

Question 26

what are the other health risks of alcohol-related liver disease? | 7

Answer 26

* alcohol dependence and withdrawal * cardiovascular disease * stroke * oesophageal, stomach and bowel cancer * dementia * depression * pancreatitis

Question 27

what is non-alcoholic fatty liver disease?

Answer 27

exessive fat deposition in liver tissue leading to impaired hepatocyte function

Question 28

what are the stages of non-alcoholic fatty liver disease? | 5

Answer 28

1. healthy 2. fatty liver 3. steatohepatitis 4. fibrosis 5. cirrhosis

Question 29

what is factors are associated with non-alcoholic fatty liver disease? | 6

Answer 29

* obesity * type 2 diabetes * poor diet * sedentary lifestyle * smoking * hypertension

Question 30

how is non-alcoholic fatty liver disease managed? | 3

Answer 30

* weight loss * control of cholesterol * reducing alcohol intake

Question 31

what is viral hepatitis? how does it affect the liver?

Answer 31

blood borne viruses that can be transmitted sexually, vertically (mother to child) and IV drug use * causes chronic liver disease by infecting hepatocytes, damaging them, resulting in loss of function

Question 32

what are the dental implications of liver disease? | 3

Answer 32

* **increased bleeding risk** = reduced coagulation factor and thrombopoietin (TPO), and increased breakdown of platelets in spleen * **impaired drug metabolism** = less plasma proteins for drug binding, more free drug in blood * **alcohol** = oral cancer risk, non-carious tooth surface loss (NCTSL), interaction with metronidazole

Question 33

what blood tests can be used to assess liver disease patients? | 4

Answer 33

* **full blood count (FBC)** - platelet count <50x10^9/L bad * **liver function test (LFT)** - bilirubin, albumin and liver enzymesn (for liver inflammation) * **coagulation screen** - intrinsic and extrinsic pathways of coagulation cascade * **INR** - time taken for blood to clot