Liver Function Tests and Liver Injury Flashcards

Flashcards for Liver Function Tests and Liver Injury

Glucuronidation

The process where bilirubin is conjugated with glucuronic acid in hepatocytes.

Alanine Transaminase (ALT)

An enzyme that transfers an amine group to pyruvate to form alanine, present in hepatocyte cytosol and other tissues; its release into blood indicates hepatocyte damage.

Aspartate Transaminase (AST)

An enzyme that transfers an amino group to oxaloacetate to form aspartate, present in hepatocyte cytosol and mitochondria; its release into blood indicates hepatocyte damage, also found in muscle tissue.

Alkaline Phosphatase (AP)

A hydrolase enzyme that removes phosphate groups from nucleotides, proteins, and alkaloids, produced by liver (biliary canaliculi), placenta, bone, and intestine.

Gamma-Glutamyl Transpeptidase (GGT)

An enzyme that transfers the y-glutamyl of glutathione to an acceptor, present in the liver (biliary system), kidney, pancreas, spleen, heart, and brain.

Serum Albumin

A protein synthesized only by the liver, present in serum, binds fatty acids, bilirubin, calcium, and hormones, and is critical in maintaining plasma osmotic pressure.

Prothrombin Time (PT)

A measure of the extrinsic pathway of coagulation that determines the ability of blood to clot; it is a measure of factors I, II, V, VII, and X activity.

Gilbert's Syndrome

A condition characterized by unconjugated hyperbilirubinemia, affecting about 5% of the population.

Cholestasis

A condition where bile cannot flow properly, leading to increased alkaline phosphatase levels.

Warfarin

A vitamin K antagonist used as an anticoagulant.

Hepatitis

Inflammation of the liver characterized by the presence of inflammatory cells in the tissue of the organ

Steatosis

Also known as fatty liver. Accumulation of lipids in hepatocytes

Acetaldehyde

Toxic metabolite of alcohol (ethanol) causes cell injury in hepatocytes

Liver Regeneration

The process of renewal and restoration of liver tissue after injury that leads to rapid proliferation and restoration of functional liver tissue

Liver Fibrosis

Accumulation of extracellular matrix in liver tissue. Similar to scarring in wound healing

Hepatic stellate cells

Liver cells capable of trans-differentiation into myofibroblasts, which is a key event in hepatic fibrogenesis

Myofibroblasts

Contractile cells created after transdifferentiation of hepatic stellate cells responsible for synthesis of collagen

Transforming Growth Factor Beta (TGF-beta)

Cytokine that controls proliferation, cell differentiation and other cell functions, important in modulation of liver regeneration and fibrosis

Hyperbilirubinemia

Elevated levels of bilirubin within the blood

Jaundice

Yellowing of the skin as a result of high levels of bilirubin

Ascites

Fluid accumulation in the abdomen

Spider Naevi

A pattern of swollen blood vessels

Hepatic wound healing

The process of liver regeneration and remodelling

Transdifferentiation

Process where quiescent hepatic stellate cells turn into activated myofibroblasts

Hepatocyte

A cell of the main parenchymal tissue of the liver

Kupffer Cells

Specialized cells localized in the liver constituting the largest population of resident macrophages in the body

Cholangitis

Infection of the bile duct

Biliary obstruction

Blockage of the bile ducts that prevents bile from draining from the liver

Cirrhosis

Late stage of scarring (fibrosis) of the liver caused by many forms of liver diseases and conditions

Fe2+

Redox state of iron in haemoglobin, also known as Ferrous

Fe3+

Redox state of iron in haemoglobin, also known as Ferric

Bilirubin

Orange-yellow pigment formed in the liver by the breakdown of hemoglobin and excreted in bile

Urobilin

Gives the yellow color to urine

Stercobilin

Gives the brown color to feces

Vitamin K

Vitamin that plays an important role in blood clotting