Liver and gall disease

Question 1

The normal liver

Answer 1

Right lobe

Left lobe

Question 2

The portal circulation ‘the third arm’

Answer 2

Portal vein
Umbilical vein
Pancreas
Spleen
Inferior mesenteric vein
Superior mesenteric vein
-nutrients from gut into liver

Question 3

Bile flow

Answer 3

Produced in liver as primary bile acids –> bile salts
Helps to digest food
Primary and secondary bile acids

Question 4

Functions of liver

Answer 4

Approx 500 different functions
Detoxification
-filters and cleans blood of waste products 
-drugs, hormones
Immune functions
-fights infections and diseases
-RE system
Iinvolved in synthesis of clotting factors, proteins, enzymes, glycogen and fats
Production of bile and breakdown of bilirubin
Energy storage (glycogen and fats)
Regulation of fat metabolism
Ability to regenerate

Question 5

Microanatomy

Answer 5

Organised in lobules with central (hepatic vein)

Hexagon - portal triads in the “corner”

Question 6

Types of liver injury

Answer 6

Acute
–>viral (A,B, EBV), drugs, alcohol, vascular –> liver failure
–> recovery
Chronic
–>recovery
–>cirrhosis –> liver failure (varices, hepatoma)
–> alcohol, viral (B, C), autoimmune, metabolic (iron, copper) –> liver failure (varices, hepatoma)

Question 7

Presentation of acute liver injury

Answer 7

Asymptomatic
abnormal LFTs
Malaise, nausea, anorexia
Jaundice 
Confusion - think ALF
*rarer*:
Bleeding 
Liver pain

Question 8

Presentation of chronic liver injury

Answer 8

Ascites, oedema
Haematemesis (varices)
Malaise, anorexia, wasting 
Easy bruising
Itching
Hepatomegaly, 
Abnormal LFTs
*rarer*:
Jaundice
Confusion

Question 9

Serum “liver function tests” (LFTs)

Answer 9

Albumin
ALP – Alkaline phosphatase
GGT – gamma GT
ALT – Alanine Aminotransferase
AST – Aspartate Aminotransferase
Bilirubin 
Globulin 

Prothrombin time (PT)/ INR
Platelet count
-normal LFTs and normal PT and platelet count do not exclude liver disease/ cirrhosis, but while normal the function is relatively preserved

Question 10

Albumin
Bilirubin
Prothrombin time (PT)

Answer 10

Give some index of liver function

-if normal would suggest a “preserved” liver function

Question 11

ALP – Alkaline phosphatase
GGT – gamma GT
AST – Alanine Aminotransferase
ALT – Aspartate Aminotransferase

Answer 11

Give no index of liver function

Question 12

Jaundice causes

Answer 12

Pre-hepatic
-haemolysis
Hepatic
-cirrhosis
-acute hepatitis (viral, alcoholic, autoimmune, drug-induced)
-infiltration of the liver by tumours
Post-hepatic (obstruction of biliary outflow)
-gallstones
-external compression: pancreatitis, lymphadenopathy, pancreatic tumour, ampullary tumour

Question 13

Bilirubin metabolism and excretion

Answer 13

Breakdown product of haemoglobin
Metabolised in liver
Excreted via intestine (and renally)
If bilirubin rises and is not excreted the motion turns pale
Bilirubin metabolism can be interrupted at various points

Question 14

Cirrhosis of the liver

Answer 14

Scarring of the liver
Result of chronic longstanding damage to the liver
Scar tissue replaces healthy tissue (exceed healing capacity of liver) –> leading to disruption of liver architecture
> resistance to blood flow through the liver, leading to portal hypertension and its complication

Question 15

Causes of chronic liver disease: most common

Answer 15

Alcohol
Non Alcoholic Steatohepatitis (NASH)
Viral hepatitis (B, C)

Question 16

Jaundice

Answer 16

Mild can be difficult to spot (light; skin tone)
Scleral jaundice usually first noted
Due to > bilirubin

Question 17

Less common causes of chronic liver disease

Answer 17

Immune
-autoimmune hepatitis
-primary biliary cirrhosis
-primary sclerosing cholangitis
Metabolic
-haemochromatosis
-Wilson’s
-alpha 1 antitrypsin deficiency…
Vascular
-Budd-Chiari
Drugs
-amiodarone

Question 18

Alcoholic liver disease

Answer 18

Commonest cause of cirrhosis in the UK

Deaths from ALD rising dramatically

Question 19

Weekly safe limits

Answer 19

14 units

Question 20

Harmful drinking

Answer 20

15-28 units

Question 21

Hazardous drinking (very heavy)

Answer 21

> 28 units

Question 22

Binge drinker

Answer 22

Men = >10 units in one session
Women = >7 units in one session

Question 23

The burden of alcohol

Answer 23

9 million adults in the UK who are drinking over the recommended daily limits
People aged 16-24 are the heaviest drinkers
In inner city A&E departments approximately 75% of patients attending after midnight are drunk
20% of patients admitted to hospital for illnesses unrelated to alcohol, are drinking at hazardous levels

Question 24

Taking an alcohol history

Answer 24

1 unit = 8g EtOH
= half pint normal beer/ lager
= small glass of wine
= pub measure of spirits

Question 25

Hepatitis B

Answer 25

``` DNA virus Reads in hepatocyte genome Persists in liver even if no longer in blood Can reactivate Mainly transmitted via intercourse/ vertically Early infection: chronicity Vaccination available Longterm treatment ```

Question 26

Hepatitis C

Answer 26

RNA virus Mainly transmitted through IVDA; needles blood products Once cleared = cleared Reinfection possible - no immunity Time limited treatment - well tolerated, 90% cure No vaccination

Question 27

Non-alcoholic fatty liver disease

Answer 27

``` On the rise; often unrecognised Risk factors -diabetes -obesity -hypertension -dyslipidaemia = metabolic syndrome LFTs may be normal; even in advanced disease Affecting 20% of Western population ```

Question 28

Iceberg of fatty liver disease

Answer 28

``` HCC NASH CirrhosisNASH NAFLD with abnormal LFT NAFLD normal LFT Normal liver ```

Question 29

UK HCV prevalence

Answer 29

``` <1% 2-400,000 IV drug use Medical treatment abroad Blood donation screening 1991 ```

Question 30

Complications of cirrhosis

Answer 30

``` Portal hypertension -ascites -varices ± haemorrhage -hypersplenism → thrombocytopenia (↓ platelets) Hepato-renal syndrome Encephalopathy Hepatocellular carcinoma ```

Question 31

Portal hypertension

Answer 31

< platelets (thrombocytopenia)

Question 32

Signs of chronic liver disease

Answer 32

Jaundice -sign of decompensation in chronic liver disease Leuconchia -white nails fro hypoalbuminaemia (not liver disease specific) Palmar erythema Spider naevi -sign of advanced liver disease but does not imply decompensation Gynaecomastia -sign of liver disease (related to low testosterone) but can also be drug related (spironolactone) Finger clubbing -not liver specific Ascites -advanced liver disease - decompensation

Question 33

Dental considerations for pts with liver disease

Answer 33

Potential for increased bleeding in patients with liver disease -coagulopathy -thrombocytopenia Potential for increased drug toxicity in patients with advanced liver disease -caution should be used in prescribing medications metabolized in the liver Infection risk, consider extra precautions if higher risk of injury (double gloves) Hep B vaccination HCV now very treatable

Question 34

Dental considerations in practice in liver disease

Answer 34

Comprehensive medical and dental histories Appropriate laboratory investigations -full blood count (FBC) -prothrombin Time (PT) -LFTs Consultation with and/or referral to treating physician(s) prior to dental treatment Minimization of soft tissue trauma during dental procedures Consideration of hospital setting for advanced surgical procedures or severely coagulopathic pts

Question 35

Stages of (chronic) liver disease

Answer 35

``` NCPH = non-cirrhotic portal hypertension -often due to vacular problems in liver -tolerating bleeding well and clotting generally intact -relatively rare (pts generally aware) Pre-cirrhotic -no effect on dental work -may be asymptomatic Liver cirrhosis ```

Question 36

Dental considerations in liver disease - medications

Answer 36

Caution in prescribing meds metabolised in liver and/ or impair haemostasis -anaesthetics: local (amides) and general (halothane) -spot antiplatelet (aspirin) 7 days before -increased DILI with flucoloxacillin and co-amoxylav -sedatives Potential for increased drug toxicity in pts with advanced liver disease -avoid NSAIDs -paracetamol is safest pain killer in liver disease -opiates: slow and low

Question 37

Spotting liver cirrhosis

Answer 37

``` Compensated -invisible -blood can be normal -risk low Decompensated -visible -abnormal blood tests -risks high ```

Question 38

Prognosis in cirrhosis (diagram)

Answer 38

``` Time (big to small) Bilirubin (small to big) Albumin (big to small) -as it gets lower ascites develops INR small to big Encepalopathy over time ```

Question 39

Complications of chronic liver disease: chronic

Answer 39

Malnutrition | Bone disease

Question 40

Complications of chronic liver disease: acute

Answer 40

``` GI bleeding and ascites (due to portal hypertension) Jaundice Hepatic encepalopathy Renal impairment Coagulopathy Infection ```

Question 41

Treatment of liver disease: symptomatic

Answer 41

Diuretics Nutrition support Supplements Propanolol

Question 42

Treatment of liver disease: specific

Answer 42

``` Antiviral Immunosuppression Relieving obstruction Venesection Detox from alcohol ```

Question 43

Hepatic encephalopathy

Answer 43

One of several features of decompensation Difficult to spot if subtle Can present as overt confusion in patient with CLD Often more troublesome for other than pt, but can be disabling Indicates underlying problem -bleed -infection -compensation -worsening chronic disease Collateral history

Question 44

Recognising hepatic encephalopathy

Answer 44

Confusion Altered behaviour Coma Collateral history

Question 45

How to test for hepatic encephalopathy

Answer 45

``` Serial 7s from 100 "baby hippopotamus" 5-star drawing Number connection test Ammonia level >50 (poor correlation) ```