Ix of liver disease Flashcards
Give 5 major functions of the liver
Carbohydrate metabolism Fat metabolism Protein metabolism Hormone metabolism Drugs and foreign compounds Storage Metabolism and excretion of bilirubin
3 main categories of liver disease
hepatitis
cirrhosis
tumours
hepatitis disease process
Damage to hepatocytes
disease process of cirrhosis
Increased fibrosis
Liver shrinkage
Decreased hepatocellular function
Obstruction of bile flow
are biochemical tests for the liver sensitive for hepatic function?
No
what can biochemical assessment of liver function tell us?
- Can be highly sensitive indicators of liver damage
- Looking at patterns of results: Inflammatory / hepatitic OR Cholestatic
- Monitoring
3 main liver enzymes
- transaminases- ALT, AST
- alkaline phosphatase
- Gamma glutamyl transferase
where is ALT found
hepatocytes and skeletal muscle
where is AST found?
hepatocytes, cardiac/skeletal muscle and erythrocytes
where is alkaline phosphatase found
biliary system, bone, placenta, intestines
where is GGT found
hepatocytes- induced by drugs, alcohol
biliary system
6 proteins associated with LFTs
albumin clotting factors a1 antitrypsin a-fetoprotein caeruloplasmin ferritin
what is a-fetoprotein useful for?
marker of hepatocellular carcinoma
what are low levels of caeruloplasmin associated with?
Wilson’s disease
basic metabolism of bilirubin
SPLEEN: Hb–> globin and haem. Haem–> iron and bilirubin
LIVER: unconjugated bilirubin (bilirubin-albumin) is conjugated in the liver to bilirubin diglucuronide and albumin is recycled.
INTESTINES: bilirubin–> urobilinogen. Urobilinogen is either excreted from the large intestines or travels in the portal vein back to the liver, or to the kidney for excretion.
when is GGT used?
laboratory when required to assist in interpretation of a raised ALP
Pattern of LFTs in inflammatory pattern (hepatocellular damage)
N to raised bilirubin v high ALT n to raised ALP N albumin N to raised GGT
Pattern of LFTs in cholestatic pattern
raised to v raised bilirubin N to raised ALT raised to v raised ALP N albumin raised to v raised GGT
Most common causes for raised transaminases
non-alcoholic steatohepatitis (fatty change plus inflammatory change)
non-alcoholic fatty liver
drug related liver damage
normal liver
alcohol related liver damage
AI hepatitis
characteristics of non-alcoholic fatty liver disease
Increased body weight increased HBA1c or fasting glucose increased/normal ALT normal AST AST:ALT ratio <0.8 Increased/normal GGT Increased triglycerides Low HDL cholesterol N mean corpuscular volume
characteristics of alcoholic fatty liver disease
variable weight normal HBA1c/ fasting glucose increased/N ALT increased AST AST:ALT >1.5 increased GGT variable TG Increased HDL cholesterol Increased mean corpuscular volume
characteristics of alcoholic fatty liver disease
variable weight normal HBA1c/ fasting glucose increased/N ALT increased AST AST:ALT >1.5 increased GGT variable TG Increased HDL cholesterol Increased mean corpuscular volume
are conventional liver function tests helpful in assessing fibrosis
No
what is the FIB4 test?
used in fibrosis
age [yr]x AST [U/L]) / ((PLT [109/L]) x (√ALT [U/L])
