Jaundice Flashcards
What would you look for when liver disease is present?
Characteristic serological patterns by performing liver function tests.
Increased AST/ALT
Increased AP/gGT
Decreased Albumin levels.
What is Jaundice?
Yellow discolouration of the skin, eye and other tissues.
Caused by a build up of bilirubin in tissue fluids and bloodstream.
(excess of bilirubin 2mg/ml)
What are the 3 causes of jaundice?
Prehepatic - jaundice caused without liver disease but by another issue
hepatic - caused by something in the liver
PostHepatic - Caused by something after the liver has functioned.
How is bilirubin produced and how much?
Product of Haem catabolism.
Produced from red blood cells, myoglobin, cytochromes and peroxidases.
(need lots for excretion of substances and for digestion)
produce 250-330mg/day
How is bilirubin metabolised?
Haem is broken down into Unconjugated bilirubin (lipid soluble) and Iron.
Bilirubin is transported to the liver by albumin.
The bilirubin gets conjugated with glucuronic acid by UDP glucuronyltransferase to form conjugated bilirubin (water soluble).
Excreted into bile where some can be metabolised in the gut, some is reabsorbed and sent back to the liver and some is excreted in urine.
What is found in Prehepatic Jaundice?
Not caused by the liver: (suggested issue with haemolysis) Total bilirubin - Normal/increased Unconjugated bilirubin - Normal/increased Conjugated bilirubin - Normal Urobilinogen - Normal/increased Urine colour - Normal Stool colour - Normal AST/ALT levels - Normal ALP/gGT levels - Normal
What is gilberts syndrome?
Mutation leading to not fully functioning conjugating enzymes for bilirubin leading to elevated unconjugated bilirubin levels.
What is neonatal Jaundice
Pretty common (up to 90% of babies more if premature) delay in clearance of bilirubin from red cell breakdown which is treated by phototherapy.
What is hepatic jaundice?
Caused by damage to the liver. Total bilirubin - Increased Unconjugated bilirubin - Increased Conjugated bilirubin - Increased Urobilinogen - Decreased Urine colour - Dark (urobilinogen + conjugated bilirubin) Stool colour - Normal/pale AST/ALT levels - Increased ALP/gGT levels - Increaesd
What is viral hepatitis?
Virus that selectively infects hepatocytes (A-E)
Leads to a very strong immune response that causes severe hepatitis.
Jaundice may or may not occur or may happen later on in hep B/C
What is Post hepatic jaundice?
Downstream of the liver and therefore is more often due to issues not affecting the liver. Total bilirubin - Increased Unconjugated bilirubin - Normal Conjugated bilirubin - Increased Urobilinogen - Decreased/negative Urine colour - Dark (conjugated bilirubin) Stool colour - pale AST/ALT levels - Increased ALP/gGT levels - Increaesd
What can be caused by cancer of the pancreas?
Growth obstructs the bottom of the common bile duct
painless jaundice often with weight loss.
common in older patients
If someone has jaundice as a result of chronicalcoholic liver disease, what would be the result?
increased conjugated and total bilirubin with dark urine and pale stools
why would the presence of pale stools and dark urine be of concern in a baby with jaundice?
suggestive of liver disease due to a lack of conjugation of bilirubin
if someone has jaundice as a result of gallstones, what would be their likely clinical findings?
pale stools
dark urine
normal unconjugated bilirubin levels
increased conjugated bilirubin levels
What is the difference between unconjugated and conjugated bilirubin?
Unconjugated bilirubin is Lipid soluble
Conjugated Bilirubin is water soluble
What is the process of conjugation?
UCB is converted to conjugated bilirubin with the addition of glucuronic acid by UDP glucuronyltransferase.
What happens after conjugation of bilirubin?
Now it is water soluble and so can be excreted by the liver in bile into the small intestine.
What happens to conjugated bilirubin in the small intestine / large intestine.
Converted to urobilinogen by intestinal bacteria where the glucuronic acid is removed.
Urobilinogen is lipid soluble.
What happens to urobilinogen?
Some is reabsorbed into the blood where it is either sent to the liver (recycled) or kidneys (urinary excretion)
Some is converted to stercobilin to be excreted.
What are the causes of prehepatic jaundice?
Haemolytic anaemia - Red cell destruction
Sickle cell disease
What causes hepatic jaundice?
Caused by liver injury from failure of cellular mechanisms of excretion of conjugated bilirubin,
Acute Hepatitis or chronic hepatitis and cirrhosis.
Cholestasis - Interuptionto bile flow
What are the causes for post hepatic jaundice?
Can be caused by gallstones, cancer/inflammation of the ducts or compression of the ducts.
Pancreatic cancer - Obstructs the bottom of the common bile duct.
What can increase conjugated bilirubin in the bile lead to?
Pigmented (bilirubin) gallstones
