Week 3.1 - LFT's and Jaundice Flashcards
What nutrients does the liver store?
glycogen, vitamin A, D, B12 and K, copper, iron
What are 8 liver function tests?
- alkaline phosphatase
- aminotransferase
- albumin
- bilirubin
- creatine
- gamma GT
- prothrombin
- platalet count
Why is bilirubin test significant?
biproduct of haem metabolim. high level is result of excess haemolysis, parenchymal issue and obstructive issue
Why is alkaline phosphatase test significant?
directly produced as enzyme in bile ducts. obstruction causes elevated levels. not specific - other organs have ALP too.
Why is Gamma GT test significant?
non-specific liver enzyme. if ALP and this both elevated, confirms liver source of ALP
Why is aminotransferases test significant?
enzymes in hepatocytes and bile ducts. ALT more specific than AST, but ratio of both help diagnose alcohol liver disease. suggest hepatocyte involvement
Why is albumin test significant?
albumin made in liver. if low, chronic liver disease suggested.
also low if lost from body due to renal issue, or in malnutrition
Why is prothrombin time significant?
made in liver. shows degree of liver dysfunction. helps assessing who needs transplant and when
Why is creatine test significant?
considered kidney function but has implications on liver disease. also determines survival and who needs transplant
Why is platelet count significant?
low platelets is result of hypersplenism. this is caused by portal hypertension. so indirect marker of portal hypertension
What symptoms occur when the liver stops working(4)?
- jaundice
- variceal bleeding
- ascites
- hepatic encephalopathy
What is jaundice?
yellowing of the skin due to excess circulating bilirubin
What are the 3 types of jaundice?
pre hepatic, hepatic and post hepatic
What suggests pre-hepatic cause?
- normal colour of urine as bile is unconjugated so not in liver.
- history of anaemia
What suggests hepatic cause?
- bright urine
- liver disease
- decompensation - ascites, variceal, bleeding, hepatic encephalopathy
What suggests post-hepatic cause?
bright urine
abdominal pain
cholestasis
What may you see on examination of pre, hepatic and post?
pre - splenomegaly, pallor
hepatic - chronic liver disease, spider veins, ascites, asterixis
post - palpable gallbladder
How do you investigate jaundice via screening? whats beneficial?
ultrasound - shows:
- extrahepatic or intrahepatic,
- what and where,
- portal hypertension,
- splenimegaly,
- cancer and staging
What tests can you do for jaundice to investigate?
- liver screen
- hep B/C serology
- autoantibody profile
- serum IgG
- ferritin and transferrin
- copper levels
- fasting glucose
- lipid profile
What is CT/MRI vs ultrasound argument?
CT more expensive and radiation, but they both have greater sensitivity. ultrasound has low sensitivity. ultrasound widely available.
ERCP vs MRCP?
ERCP injects dye, goes in via endoscopy and can take out stones and put in stents. Therapeutic sand diagnostic. needs sedation - complications.
MRCP is a scanner - claustrophobia. only diagnostic
What is a cholidoscope?
smaller endoscope that can get into papilla. for cholidocholithiasis
When do we use PTC?
if ERPC isnt possible and need to go higher up in bile duct. need to puncture liver from top to enter - more invasive
Why is EUS special?
can take fine needle aspiration of tumours and cysts - biopsies, and view canaliculi. can stage tumours
When would you carry out a liver biopsy?
- assess jaundice and liver disease when no biliary dilatation.
- gives definite diagnosis of certain conditions, e.g. autoimmune hepatitis,
- confirms others like PBC. can stage alsohol hepatitis and NAFLD.
