Cite this page: Arora K. Physiology. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/liverjaundicephysiology.html. Accessed December 13th, 2019.
Definition / general
- Total bilirubin > 2.0 mg/dl (normal is 0.3 to 1.2 mg/dl)
- Conjugated bilirubin (produced by normal liver) is water soluble, nontoxic, loosely bound to albumin; can be excreted in urine
- Unconjugated bilirubin and bilirubin glucuronides are insoluble in water and tightly complexed to albumin; cannot be excreted in urine despite high levels due to insolubility; may diffuse into tissues and produce toxic brain injury
- Hemolytic disease of newborn (erythroblastosis fetalis) causes severe neurologic damage (kernicterus) due to accumulation of unconjugated bilirubin
- Excessive production of bilirubin that overwhelms livers conjugating capacity, reduced hepatocyte uptake of bilirubin, other causes of impaired conjugation, decreased hepatocyte excretion of bilirubin, impaired bile flow (intra or extrahepatic)