LFTs Flashcards
What are the two measurable aminotransferases?
Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST)
What do altered liver enzymes reflect?
Enzymes leak due to hepatocellular damage so they reflect liver injury only!
What are the sources of ALT?
Liver only
What are the sources of AST?
Liver, heart, skeletal muscle, kidneys, pancreas
What causes a marked increase in AST/ALT (1000s)?
Toxin/drug-induced hepatitis (e.g. paracetamol OD)
Acute Viral Hepatitis
Liver Ischaemia
What causes a modest increase in ALT/AST (300-500)?
Chronic/alcoholic/autoimmune hepatitis, biliary obstruction
What causes a mild increased in ALT/AST?
Cirrhosis, NAFLD, hepatocellular carcinoma, wilson’s, haemochromatosis
What causes a marked rise in ALP and a rise in AST?
Cholestasis (ALP>AST)
What causes a moderate increase in ALP and large rise in AST?
Hepatitis, cirrhosis, infiltration
What is gamma-glutamyltransferase used for?
Mirrors ALP so used to confirm if ALP is of hepatic origin
Raised with alcohol abuse (+ increased MCV) and with enzyme-inducing drugs
What are the functional liver tests?
Albumin, prothrombin time and INR
What causes decreased albumin and decreased protein?
advanced cirrhosis, alcoholism, protein malnutrition, chronic inflammation, renal/gut/skin loss
What causes decreased albumin and normal protein?
Infection
What causes decreased albumin and raised protein?
Myeloma
What causes a raised INR?
Liver disease (with impaired function), vitamin K deficiency, consumptive coagulopathy (e.g DIC)
