Microscopic anatomy of the liver and cirrhosis Flashcards
How much does a normal liver weigh?
1500g
What are the 3 main structures found in the portal tract?
Hepatic artery
Hepatic vein
Bile duct
What is the main cause of death due to alcohol toxicity?
Respiratory failure
List the stages of chronic alcoholic liver disease?
Fatty liver (steatosis)
Hepatitis
Cirrhosis
What enzyme is usually raised in chronic alcoholic liver disease?
Gamma glutamyl transferase
List some examples of liver function tests
Bilirubin Total protein Albumin Alanine Transaminase (ALT) Aspartate Transaminase ( AST) Alkaline Phosphatase( ALP) Gamma Glutamyl Transferase ( GGT)
What may be found on haematological tests of a person with chronic alcoholic liver disease?
Iron deficiency anaemia- lack of food
Folate and vitamin B12 deficiency
Raised INR- clotting factor dysfunctions- lack of vitamin K
Why do patients with chronic liver disease bleed lots?
Lack of suitable clotting factors and vitamin K
Describe the pathogenesis of alcoholic steatosis
Increased precursors for fat synthesis
Reduced breakdown of fat
Reduced hepatic excretion of fat
Fatty change of the liver is reversible on abstention
List some causes of non-alcoholic fatty liver disease
- Obesity
- Type 2 diabetes
- Drugs- methotrexate
- Infection- hepatitis C
Describe acute hepatitis
May be associated with jaundice
Patient will be very unwell
Polymorphs/neutrophils in the liver
Describe chronic hepatitis
If the patient does not abstain, there is a risk of progression to fibrosis and cirrhosis
Lymphocytes infiltrate in the liver
What does a green stain on biopsy represent?
Fibrosis
Describe alcoholic cirrohsis
Irreversible end stage liver disease
Hallmark of cirrhosis – fibrosis/scarring and nodularity
Repeated inflammation and the healing process → regeneration of hepatocytes into nodules separated by scar tissue
How is alcoholic cirrhosis classified?
Classified according to size of the nodules
Macro-nodular >3 mm
Micro-nodular < 3 mm
Which sized nodule is most likely to develop into cancer?
Macro nodular
List the causes of cirrhosis
alcohol (60 - 70% ) viral hepatitis ( B, C, D, E etc ) primary biliary cirrhosis primary haemochromatosis Wilson’s disease alpha-1-antitrypsin deficiency Cryptogenic
What are the complications of cirrhosis?
Portal hypertension
Liver failure
Ascites
Hepatocellular carcinoma
What are the signs of liver failure?
Jaundice
Hypoproteinaemia
Bleeding
Hepatic encephalopathy
Describe portal hypertension. Explain why this is dangerous
The fibrosis causes portal hypertension
Blood flow through the liver is impeded
Blood finds an alternative route to the heart via the spleen and oesophagus leads to collateral circulation enlarged spleen & oesophageal varices
Risk of bleeding from varices – medical emergency
What is the triad of portal hypertension?
Oesophageal varices
Cirrhosis
Splenomegaly
List some causes of bleeding in an alcoholic patient
Oesophageal varices Peptic ulcer Mallory Weiss tear Haemorrhagic gastritis Reflux oesophagitis with ulceration
What are mallory weiss tears?
Mallory Weiss tears occur at the oesophago-gastric junction when the patient vomits and retches against a closed cardiac sphincter
What causes peptic ulcers?
The main causes of peptic ulcers are Helicobacter infection and Non-Steroidal Anti-Inflammatory Drugs (NSAIDS)
Give some causes of death related to alcohol
Alcohol Toxicity ≤ 300mg/dl - novice drinker
≥ 350mg/dl - habitual drinker
RTAs: Legal limit 35mg/dl in breath ; 80mg/dl in blood
Sudden death in fatty liver due to metabolic acidosis resulting in arrhythmias
Haemorrhage:
Oesophageal varices
Acute gastritis/Peptic ulcer
Liver failure – acute/cirrhosis
Describe hepatocellular carcinomas and how they are diagnosed
Hepatocellular carcinoma (HCC) can arise as a complication of cirrhosis due to any cause, but alcohol related HCC is increasing The blood test for HCC is alpha feto - protein, which is raised, but not in all cases Most common tumours are metastatic from GIT cancers
List some complications of gall stones
Biliary colic Acute cholecystitis Empyema of gallbladder Perforation of gallbladder Mucocoele of gallbladder Porcelain gallbladder Carcinoma of gallbladder Obstructive jaundice Secondary biliary cirrhosis Ascending cholangitis Liver abscess Pancreatitis Gallstone ileus
