jaundice Flashcards
what causes jaundice?
high levels of billrubin, which a breakdown product from the catabolism of haem
usually is conjugated within the liver then excreted bia bile. jaundice occours when the pathway is obstructed.
what is prehepatic jaundice?
occours when there is excessive red cell breakdown which overwhelms the livers ability to conjugate bilirubin, causing hyperbilirubinaemia.
unconjugated bilirubin remains in the bloodstream
what is intrahepatic jaundice?
dysfunction of hepatic cells so liver loses ability to conjugate bilirubin
May also become cirrhotic and compress intrahepatic portions of bilary tree to cause obstruction.
leads to both unconjugated and conjugated bilirubin in the blood.
what is post hepatic jaundice?
obstruction of biliary drainage. The bilirubin that is not excreted will have been conjugated by the liver, hence the result is a conjugated hyperbilirubinaemia.
common causes of pre hepatic jaundice?
- Haemolytic anaemia
- Gilbert’s syndrome
common causes of intrahepatic jaundice?
- Alcoholic liver disease
- Viral hepatitis
- Iatrogenic, e.g. medication
- Hereditary haemochromatosis
- Autoimmune hepatitis
- Primary biliary cirrhosis or primary sclerosing cholangitis
- Hepatocellular carcinoma
common causes of post hepatic jaundice?
- Intra-luminal causes, such as gallstones
- Mural causes, such as cholangiocarcinoma, strictures, or drug-induced cholestasis
- Extra-mural causes, such as pancreatic cancer or abdominal masses (e.g. lymphomas)
what type of jaundice is dark wee and light poo present in?
dark (‘coca-cola’) urine manifests in conjugated or mixed hyperbilirubinaemias, whereas normal urine is seen in unconjugated disease as it isnt water soluble.
obstructive jaundice will give pale stools, due to the reduced levels of stercobilin entering the GI tract, which normally colours the stool.
what investigations can be done for jaundice?
- LFT
- Coagulation studies
- FBC and U&E
- specialist blood tests e.g bilirubin, albumin, AST and ALT, ALP, alakaline phosphatase and gamma GT.
what is the significance of specialist blood test in jaundice?
- billirubin quantifies degree of jaundice
- Albumin marks liver synthesising function
- AST/ALT indicate hepatocellular injury
- Alkaline phosphatase/ALP is raised in billiary obstruction
- Gamma- GT is specific for bilary obstruction but not routinely preformed
what imaging can be done for jaundice?
- USS abdomen first line to identify any obstructive or gross liver pathology
- Magnetic resonance cholangiopancreatography (MCRP) can be used to visulise billary tree, typically if jaundice is obstructive.
- can do liver biopsy when diagnosis is not made despite above investigations
what is the management for jaundice?
- obstructive = removal of gallstone through endoscopic retrograde cholangiopancreatography (ERCP)
- symptomatic treatment for symptoms e.g itching via creams and anti histamines
- monitor coagulopathy and treat with vit K or fresh frozen plasma (FFP) if any evidence of bleeding or rapid coagulopathy
