Approach to Jaundice Flashcards
What are the synthetic functions of the liver?
Clotting factors
Bile acids
Carbohydrates
Proteins - albumin
Lipids
Hormones
Explain detoxification in the liver
Urea production from ammonia
Detoxification of drugs
Bilirubin metabolism
Breakdown of insulin and hormones
Explain the immune function of the liver
Combats infections
Clears the blood of particles and infections including bacteria
Neutralising and destroying all drugs and toxins
Explain the storage function of the liver
Stores glycogen
Stores Vitamin A, D, B12 and K
Stores copper and iron
What is bilirubin?
Is a by product of haem metabolism
Is generated by senescent RBC’s in the spleen
What is bilirubin initially bound to before liver?
Bound to albumin which is unconjugated
Liver conjugates it
What does conjugation of bilirubin in the liver do?
Solubilises it
When can bilirubin be elevated?
Pre-hepatic - haemolysis
Hepatic - parenchymal damage
Post-hepatic - obstructive
Describe aminotransferase
Enzymes which are present in hepatocytes
ALT more specific than AST
What can AST/ALT ratio suggest?
Can point towards alcoholic liver disease
If both elevated then parenchymal involvement
Describe alkaline phosphate
Enzymes present in bile ducts
Also present in bone, placenta and intestines
What can elevated alkaline phosphate suggest?
Obstruction or liver infiltration
Describe Gamma GT
Non specific liver enzyme
Useful to confirm liver source of ALP
What does elevated Gamma GT suggest?
Can be elevated in alcohol use
Also NSAIDs can raise levels
Describe albumin
Important test for synthetic function of liver
What does low levels of albumin suggest?
Suggest chronic liver disease
Can be low in kidney disorders and malnutrition
Describe prothrombin time
Extremely important test for liver function
Tells degree of liver dysfunction as liver produces clotting factors
Describe creatine
Essentially kidney function
Determines survival from liver disease
What is platelet count a marker of?
Indirect marker for Portal hypertension
Is low in cirrhotic subjects due to hypersplenism
What are the symptoms of the liver stopping function?
Jaundice
Ascites
Variceal bleeding
Hepatic encephalopathy
What is the definition of jaundice?
Yellowing of skin, sclerae and other tissue caused by excess circulating bilirubin
When is jaundice detectable?
When plasma bilirubin levels exceed 34umol/L
What causes jaundice in pre-hepatic cases?
Increased quantity of bilirubin - haemolysis
Impaired transport
What causes jaundice in hepatic cases?
Defective uptake of bilirubin
Defective conjugation
Defective excretion
What causes jaundice in post-hepatic cases?
Defective transport of bilirubin by the biliary ducts
What are some clues on history for pre-hepatic cases?
History of anaemia
Acholuric jaundice
What are some clues on history for hepatic cases?
Risk factors for liver disease - IVDU
Decompensation - ascites, variceal bleed and encephalopathy
What are some clues on history of post-hepatitis cases?
Abdominal pain
Cholestasis - pruritus, pale stools, high coloured urine
What are clues on clinical exam for pre-hepatic cases?
Pallor and splenomegaly
What are clues on clinical exam for hepatic cases?
Stigmata of CLD - spider naevi and gynaecomastia
Ascites
Asterixis - flapping tremor
What are clues on clinical exam for post-hepatic?
Palpable gall bladder
What would a liver screen look for?
Hepatitis B and C serology
Autoantibody profile, serum immunoglobins
Caeruloplasmin and copper
Ferritin
Alpha 1 anti trypsin
Fasting glucose
What is the most important investigation for jaundice?
Ultrasound of the abdomen
What is an ERCP?
Use of endoscopy and fluoroscopy
Diagnoses and treats biliary and pancreas ducts
X ray monitored
Has more complications and issues than MRCP but is therapeutic
What is a MRCP?
Non invasive imaging to investigate intra and extra hepatic biliary tree
Can also image out with ducts
No complications
What can ERCP treat?
Dilated biliary tree by removing tumour and visible stones
Acute gallstone pancreatitis
Stenting obstruction of ducts
Post op biliary complications
What are some complications of ERCP?
Sedation related - resp. and cardio
Pancreatitis and cholangitis
Sphincterotomy - bleeding and perforation
When is percutaneous transhepatic cholangiogram (PTC) used?
ERCP not possible due to duodenal obstruction or previous surgery
Hilar stenting
Is more invasive then ERCP
When is endoscopic ultrasounds (EUS) used?
Characterising pancreatic masses
Staging of tumours
FNA of tumours and cysts
Excludes biliary microcalculi - biliary sludge
What is liver biopsy important for?
Definitive diagnosis of certain conditions - autoimmune hepatitis
Confirm diagnosis
Staging of severity
