6. Liver Function And Pathology Flashcards
What are the functions of the liver?
Storage - glycogen, vitamins, iron, copper
Synthesis - glucose, lipids/cholesterol, bile, clotting factors, albumin
Metabolic - bilirubin, ammonia, drugs, alcohol, carbohydrate, lipid
What are the symptoms of liver failure?
Jaundice
Oedema/ascites
Bleeding
Confusion
Why does oedema/ascites occur in liver failure?
Reduced ability to produce albumin - oncotic pressure
Why does confusion occur in liver failure?
Build up of ammonia as reduced ability to metabolise it
What can cause acute liver failure?
Alcohol
Paracetamol
Viral
Medications - aspirin in children
What is cirrhosis?
Scarring (fibrosis) of the liver caused by long-term liver damage
Scar tissue prevents liver working properly
What can inflammation of the liver lead to?
Fibrosis and hepatocyte necrosis
Nodules
What can cause inflammation and therefore cirrhosis?
Drugs Infection Deposition Autoimmune Other
How can drugs cause cirrhosis and chronic liver disease?
Iatrogenic - doctor given medication
Alcoholic liver disease
What happens in alcoholic liver disease?
Fatty change (weeks) - hepatomegaly Alcoholic hepatitis (years) - inflammatory cells present, jaundice, right upper quadrant pain, hepatomegaly
What infections can cause cirrhosis/chronic liver disease?
Hep B - symptoms
Hep C - IV drug use, asymptomatic
What can infections and cirrhosis of the liver cause?
Malignancy
What are some deposition disorders that can result in chronic inflammation and therefore cirrhosis?
Fat - non-alcoholic fatty liver disease (insulin resistance, triglycerides build up
Fat - non-alcoholic steatohepatitis (NASH) is when inflammation is present in NAFLD
Hereditary haemochromatosis - increased absorption of iron, therefore increased deposition
Wilson’s disease - decreased copper secretion, therefore increased deposition
How is hereditary haemochromatosis treated?
Venesection
What symptoms can Wilson’s disease cause unrelated to the liver?
CNS - seizures, memory problems, tremors
What treatment do patients with Wilson’s disease require?
Liver transplant
What autoimmune causes are there for cirrhosis?
Autoimmune hepatitis - hepatocytes attacked by immune system (ASMA, ANA)
Primary biliary cirrhosis - anti-mitochondrial antibodies
Primary sclerosing cholangitis - can have association with IBD (UC)
What are some other causes of inflammation and therefore cirrhosis?
Alpha-1 antitrypsin deficiency
Glycogen storage disorders
Budd-chiari syndrome
What are the 3 main vessels in the portal venous system drainage into the portal vein?
Inferior mesenteric vein
Superior mesenteric vein
Splenic vein
What is one of the main complications seen in cirrhosis?
Portal hypertension
Why does portal hypertension occur?
Cirrhotic liver not very expansive
Veins compressed entering liver from portal venous system
Causes increase in hydrostatic pressure within portal venous system
Leads to fluid leakage (ascites) due to low albumin
Build up of pressure in spleen (splenomegaly)
What does portal hypertension cause?
Blood shunts from portal system to systemic circulation - varices in oesophagus, anorectal, umbilicus (in severe cases)
Ascites - from increased hydrostatic pressure
Splenomegaly
Hepatorenal syndrome - reduced kidney function
What happens in hepatorenal syndrome?
Portal hypertension
Back logs in venous system and eventually in arterial system (splanchnic)
Arterial vasodilation
Perceived reduced circulating volume, RAAS system is activated, renal artery vasoconstriction
Reduced perfusion to kidney therefore reduced kidney function
What are gallstones composed of?
Cholesterol
Bile pigments
