Title 12. LIVER FUNCTION.pdf ✅

PHARMD GURU Page 1 LIVER FUNCTION LIVER ENZYMES:  Levels of certain enzymes (e.g., LDH, ALP, AST, and ALT) increase with liver dysfunction.  These enzyme tests indicate only that the liver has been damaged. They do not assess the liver’s ability to function. Other tests provide indications of liver dysfunction. SERUM BILIRUBIN:  Bilirubin, a breakdown product of Hb, is the predominant pigment in bile. Effective bilirubin conjugation and excretion depend on hepatobiliary function and on the rate of RBC turnover.  Serum bilirubin levels are reported as total bilirubin (conjugated and unconjugated) and as direct bilirubin (conjugated only).  Bilirubin is released by Hb breakdown and is bound to albumin as water- insoluble indirect bilirubin (unconjugated bilirubin), which is not filtered by the glomerulus.  Unconjugated bilirubin travels to the liver, where it is separated from albumin, conjugate with diglucuronide, and then actively secreted into the bile as conjugated bilirubin (direct bilirubin), which is filtered by the glomerulus.  Normal values of total serum bilirubin are 0.1 to 1.0 mg/dL (2 to 18 mmol/L); of direct bilirubin: 0.0 to 0.2 mg/dL (0 to 4 mmol/L). BILIRUBIN METABOLISM: CLINICAL LABORATORY TESTS USED IN THE EVALUATION OF DISEASE STATES, AND INTERPRETATION OF TEST RESULTS