Hepatobiliary pathology Flashcards
What are the 2 blood supplies to the liver?
Hepatic artery
Portal vein
What are the functions of the liver?
Protein synthesis
Metabolism of fat and carbohydrate
Detoxification of drugs and toxins
What is liver failure a complication of?
Acute or chronic liver injury
What are the causes of acute liver injury?
Hepatitis- viruses, alcohol, drugs
Bile duct obstruction
What are the causes of chronic liver injury?
Cirrhosis
What does viral hepatitis do?
Targets liver cells and causes inflammation
Causes liver cell damage and death of individual liver cells
What are the outcomes of acute inflammation in the liver?
Resolution
Liver failure
Progression to chronic hepatitis and cirrhosis
What is alcoholic liver disease?
Response of the liver to excess alcohol
What is the progression of alcoholic liver disease?
Acute inflammation –> liver cell death –> liver failure–> progression to cirrhosis
What is jaundice?
Increased circulating bilirubin causing the skin and eyes to take on a yellow tone
Caused by altered metabolism of bilirubin
What are the 3 parts of bilirubin metabolism?
Prehepatic
Hepatic
Post hepatic
What happens in the pre hepatic stage of bilirubin metabolism?
Breakdown of haemoglobin in spleen to form haemorrhage and globin
Globin converted to bilirubin
Release of bilirubin into curculation
What happens in the hepatic stage of bilirubin metabolism?
Uptake of bilirubin by hepatocytes
Conjugation of bilirubin in hepatocytes
Excretion of conjugated bilirubin into biliary system
What happens in the post hepatic stage of bilirubin metabolism?
Transport of conjugated bilirubin in biliary system
Breakdown on bilirubin conjugate in intestine
Reabsorption of bilirubin
What is the enterohepatic circulation?
Circulation of substances, such as bilirubin, from the liver to the bile, entering the small intestine, absorption into he enterocyte and transport back to the liver
What are the 3 classifications of jaundice?
Pre hepatic
Hepatic
Post hepatic
What is the pre hepatic cause of jaundice?
Increased release of haemoglobin from red cells
What are the hepatic causes of jaundice?
Cholestasis
Intrahepatic bile duct obstruction
What is cholestasis?
Accumulation of bile in hepatocytes or bile canaliculi
What causes cholestasis?
Viral hepatitis
Alcoholic hepatitis
Liver failure
Drugs- therapeutic or recreational
What are the causes of intrahepatic bile duct obstruction?
Primary biliary cholangitis
Primary sclerosis cholangitis
Tumours of the liver
What is primary biliary cholangitis?
Female predominant organ specific autoimmune disease
What is the pathology of primary biliary cholangitis?
Granulomatous inflammation involving bile ducts
Loss of intrahepatic bile ducts
Progression to cirrhosis
What is primary sclerosis cholangitis?
Chronic inflammation and fibrous obliteration of bile ducts, causing loss of intrahepatic bile ducts
What are the types of tumour of the liver?
Hepatocellular carcinoma
Tumours of intrahepatic bile ducts
Metastatic tumours
What are the post hepatic causes f jaundice?
Cholelithiasis (gallstones)
Extra hepatic bile duct obstruction
What are he risk factors of cholelithiasis?
Obesity
Diabetes
What is the pathology of cholelithiasis?
Acute or chronic inflammation
What are the causes of extra hepatic bile obstruction?
Gallstones
Bile duct tumours
Benign stricture
External compression (tumours)
What are the effects of extra hepatic bile obstruction?
No bile secreted into duodenum
Infection of bile proximal to obstruction
What is cirrhosis?
End stage chronic liver disease
Response pf the live to chronic injury
What are the causes of cirrhosis?
Alcohol Hep B, C Immune mediated liver disease Metabolic disorders Obesity Unknown cause
What immune mediated liver diseases can cause cirrhosis?
Autoimmune hepatitis
Primary biliary cholangitis
What metabolic disorders can cause cirrhosis?
Primary haemochromatosis- excess iron
Wilson’s disease- excess copper
What is the most common cause of cirrhosis?
Unknown cause
What is the pathology of cirrhosis?
Diffuse process involving the whole liver
Loss of normal liver structure
Hepatocytes replaced by fibrous tissue
What are the complications of cirrhosis?
Altered liver function- liver failure
Abnormal bloodflow- portal hypertension
Increased risk of hepatocellular carcinoma
