What is the principal pigment in bile that is derived from hemoglobin breakdown?
How does bilirubin get transported to the liver?
Bilirubin forms a complex with albumin for transport to the liver
In this form, bilirubin is unconjugated and NOT water soluble
When is bilirubin conjugated?
Conjugated in the hepatocyte endoplasmic reticulum with glucuronic acid to form bilirubin diglucuronide
The reaction is catalyzed by uridine diphosphate (UDP) glycuronyltransferase
Which form of bilirubin is water soluble, unconjugated or conjugated?
Conjugated is water soluble
What has an orange-brown pigment that gives stool its characteristic color?
What does the liver secrete to assist in digestion?
Where is bile stored?
What organ is the primary site in the body for synthesis of waste products, conjugation of hormones, and bilirubin to water-soluble forms, and conversion of drugs to metabolites for excretion in urine or stool?
What clinical condition occurs when there is excessive erythrocyte destruction (as hemolytic anemias, spherocytosis, toxic conditions, hemolytic disease of the newborn caused by Rh or ABO incompatibility)?
What clinical condition occurs when the liver cells malfunction and cannot take up, conjugate, or secrete bilirubin?
What clinical condition:
Defect in the ability of hepatocytes to take up bilirubin
Due to transport problem of bilirubin from the sinusoidal membrane to the mircrosomal region
What clinical condition is a partial or complete deficiency of UDP-glycuronyltransferase?
What clinical condition is characterized by a defective liver cell excretion of bilirubin due to impaired transport in the hepatocyte of conjugated bilirubin from microsomoal region to the bile canaliculi?
What clinical condition is characterized by a level of UDP-glycuronyltransferase is low at birth?
Neonatal physiological jaundice
What clinical condition may be caused by hepatocyte injury such as cirrhosis, bile duct injury (like Rotor syndrom or neoplasms)?
What clinical condition occurs when and obstruction blocks the flow of bile into the intestines?
(also called extrahepatic cholestasis)
What disorder is a result of chronic scarring of liver tissue turning it into nodules?
What is the tumor that is the primary cancer of the liver?
Hepatocellular carcinoma or hepatoma
What tumor arises from other cancerous tissue where the primary site was of lung, pancreas, gastrointestinal tract or ovary origin?
Metastatic liver tumors
What syndrome has an unknown cause but include symptoms of encephalopathy, neurologic abnormalities including seizures or coma, and abnormal liver function tests due to hepatic destruction?
What lab tests are markers for hepatocellular necrosis?
ALT: Most specific for hepatocyte injury
AST: Less specific than ALT
LD: Least specific
What lab tests are markers that reflect cholestasis?
What other lab tests are used to assess liver disorders?
Bilirubin (total, direct (conjugated), and indirect (unconjugated))
What test methodologies are used to measure bilirubin?
Jendrassik-Grof total bilirubin test
What are the reference ranges for bilirubin?
Infants Total Bilirubin: 2-6 mg/dL
Adults Total Bilirubin: 0.2-1.0 mg/dL
Indirect Bilirubin: 0.2-0.8 mg/dL
Direct Bilirubin: 0.0-0.2 mg/dL
What causes a decrease in urobilinogen?
What causes an increase in urine urobilinogen?
Hepatocellular disease (Hepatitis)
What is the reference range of urine urobilinogen?
0.1-1.0 Ehrlich units/2 hr
Deficiency of any of the specific enzymes that catalyze the formation of the prophyrinogens results in _________
Results in excess formation of the corresponding porphyrin
Name the clinically significant porphyrins
Name the types of porphyrias
Acute intermittent porphyria
Congenital erythropoietic porphyria
Porphyria cutanea tarda
What is the term for overproduction or accumulation of porphyrins and precursors in the bone marrow?
What is the term for overproduction or accumulation of porphyrins and precursors in the liver?
What test methodology is used to measure porphyrins?
(forms red condensation product with porphobilinogen)