Liver Disease Symposium: Introduction to Liver disease Flashcards
4 roles of the liver
- Glucose + Fat metabolism
- Detoxification + excretion
- Protein synthesis
- Defence against infection
What excretion takes place in the liver
- Bilirubin
- Ammonia
- Drugs/hormones/pollutants
Through what vessel does blood enter the liver
Portal vein + hepatic artery
What epithelium lines the hepatic artery, portal vein and bile duct
CUBOIDAL EPITHELIUM
Result of chronic liver damage
Fibrosis
What is severe fibrosis of the liver called
Cirrhosis
Presentation of liver injury
- Malaise
- Nausea
- Anorexia
- Jaundice
RARER:
- Confusion
- Bleeding
- Liver pain
- Hypoglycaemia
What would liver pain indicate
Obstruction
Presentation of chronic liver injury
- Ascites
- Oedema
- Haematemesis
- Malaise
- Anorexia
- Wasting
- Itching
- Hepatomegaly
- Abnormal LFTs
How do we test for liver function
- Serum bilirubin
- Albumin
- PTT
What cholestatic enzymes are looked at in blood tests
- Alkaline phosphatase
2. Gamma-GT
What hepatocellular enzymes are looked at in blood tests
Transaminases
Does looking at serum enzyme give an indication of liver function
No
What causes pre-hepatic jaundice
Haemolysis
Gilberts
What causes cholestatic jaundice (conjugated)
Liver disease
Bile duct obstruction
Why is PTT a good indicator of acute and chronic liver disease
Sue to its short half-life
What can cause a prolonged prothrombin time
Vit K deficiency in biliary obstruction - low conc. of bile salts causes poor absorption of vit K
In what disease is alkaline phosphatase levels raised
Intrahepatic and extra hepatic cholestatic disease - increased synthesis
Cirrhosis
Hepatic infiltration
How do bile pigments form
From harm when old/damaged erythrocytes are broken down in the spleen and liver
What is the most predominant bile pigment
Bilirubin
Where is bilirubin extracted
Hepatocytes
What colour is bilirubin
Yellow
What is haemoglobin broken down into
Haem + global
What is global broken down into
Amino acids - used to make new erythrocytes
What happens to harm
Broken down in bilirubin and Fe2+
What happens to biliverdin
Reduced to unconjugated bilirubin
Property of bilirubin
Lipid-soluble and insoluble in blood so must be bound to ALBUM
Where does bilirubin go
Glucuronidation in the liver
Describe the production of conjugated bilirubin
Action of UDP glucuronyl transferase
Why does Gilbert’s result in pre-hepatic jaundice
Lack of UDP glururonyl transferase
Where does the conjugated bilirubin go
Travels to ileum where it is reduced by bacteria into urobilinogen
What happens to urobilinogen
Some is absorbed into the blood + bound to albumin
Some is oxidised to form stercobilin
What give urine its yellow colour
Urobilinogen
What can cause post-hepatic jaundice
- Gall-stones
2. Mirizzi syndrome
What is mirizzi syndrome
Stone in gallbladder/cystic duct presses on common bile duct)
What questions should i ask as a doctor if suspected jaundice
- Dark urine, pale stool + itching
- Biliary pain (radiates to shoulder)
- Rigors
- Abdomen swelling
- Weight loss
past history
Drug history
Social history
Test for jaundice
- High AST/ALT suggests liver disease
Dilated intrahepatic bile ducts on ULTRASOUND - shows bile obstruction
What is biliary colic
Term used for pain associated with temporary obstruction of the cystic or common bile duct by a stone migrating from the gall bladder
How to detect stone-induced ductular obstruction
Sudden onset, severe but constant and has crescendo characteristic
What is cholecystitis
Gallbladder inflammation
What doe bile consist of
Cholesterol
Bile Pigments
Phospholipids
What gender do gallstones commonly effect
Females
What ethnicity do gallstones generally effect
Scandinavians
SA
NA
Symptoms of gall stones
Usually asymptomatic
Main causes of gallstones
- Obesity + rapid weight loss
- Diet high in animal fat + low in fibre
- Diabetes mellitus
- Contraceptive pill
- Liver cirrhosis
Risk factors of gallstones
- Female
- Fat
- Fertile = increased risk of gallstones
- Smoking
What is the most common type of gallstone
Cholesterol gallstones
Main causes of cholesterol gallstones
Female
Age
Obesity
How do cholesterol gallstones form
- Cholesterol crystallisation in bile
- Cholesterol held in solution by bile salts and phospholipids which form micelles and vesicles
- Cholesterol gallstones form in EXCESS cholesterol
How does an excess cholesterol arise
TOO little bile salts + phospholipids
Excess of cholesterol
Why will many people with supersaturated bile never develop stones
Balance between cholesterol crystallising and solubilising factors that determines whether cholesterol with crystallise out of solution
What other factors contribute to gallstone formation
- Reduced gallbladder motility and stasis
2. Crystalline promoting factors in bile
Main cause of bile pigment stones
Haemolysis
How do BLACK pigment gallstones from
Calcium bilirubinate and network of mucin glycoproteins that interlace with salts
In what diseases are black pigment gallstones seen in
Haemolytic anaemia
Spherocytosis
Sickle cell
Thalassaemia
What are brown pigment stones made of
composed of calcium salts
When do brown pigment stones form
Presence of bile stasis and/or biliary infection
What is the most common cause of brown pigment stones
Recurrent bile duct stones following cholecystectomy
What is the problem if gallstones become symptomatic
Start to become recurrent
Do gallstones cause dyspepsia, fat intolerance, flatulance
No
Define gallstone colic
Pain associated with temporary obstruction of the cystic or common bile duct by a stone migrating out of the gallbladder
When do symptoms for gallstone colics com in
Mid-evening + last till early hours of morning
Initially where are gallstone colics felt
Pain in epigastrium and radiates to upper right quadrant component (right shoulder + right sub scapular region)
Symptoms of gallstone colics
Nausea and committing
What is the consequence of acute cholecystitis
Obstruction of gallbladder tempting
What is acute cholecystitis caused by
Gallstones
Pathophysiology of acute cholecystitis
- Obstruction = increased gall bladder glandular secretion leading to progressive distension that may compromise vascular supply to gall bladder
How do we distinguish from cute cholecystitis from biliary colic
Inflammatory response in acute cholecystitis
Where is pain felt in acute cholecystitis
Epigastrium
What happens to the pain in acute cholecystitis over time
Localises in right upper abdominal quadrant corresponding to parietal peritoneal involvement (inflammation begins to irritate parietal peritoneum)
NON-SPECFIC symptoms of acute cholecystitis
VOMITING
FEVER
LOCAL PERITONITIS
What may happen if a stone from acute cholecystitis moves into the common bile duct
Cholangitis and JAUNDICE
Differential diagnosis of Biliary colics
- IBS
- Carcinoma on right side of colon
- Pancreatitis
Differential diagnosis of acute cholecystitis
Acute episodes of pancreatitis
Peptic ulceration
Basal pneumonia
Intrahepatic abscess
How is biliary colic diagnosed
Abdominal ultrasound
Blood tests when diagnosing acute cholecystitis
- RAISED WBC (due to inflammation) and C-reactive protein
2. Raised serum bilirubin, alkaline phosphatase and aminotransferase levels
Abdominal ultrasound in acute cholecystitis
- Thick-walled, shrunken gallbladder
- Pericholecystic fluid
- Stones
Clinical examination of acute cholecystitis
Right upper quadrant tenderness
Murphy’s signs
What is murphy’s sign
Pain on taking a deep breath when examiner places two fingers on right upper quadrant
How is acute cholecystitis and biliary colics treated surgically
Laparoscopic cholecystectomy (gallbladder removal)
When is surgical intervention for acute cholecystitis and biliary colics needed
symptomatic
How is acute cholecystitis non-surgically treated
- Nil by mouth
- IV fluid
- OPIATE ANALGESIA
- IV antibiotic - CEFUROXIME or CEFTRIAXONE
What bacteria are associated with cholecystitis
- Klebsiella
- Enterococcus
- E.coli
How are gallstones dissolved
- Increasing bile salt content
ORAL URSODEOCYCHOLIC ACID
SIMVASTATIN (lowers hcolesterol
Why is shock-wave lithotripsy done in acute cholecystitis
- Shock wave directed on gallbladder stones to turn them into fragments
When can shock wave lithotripsy be done
When cystic duct is patent - allows fragments to pass