Bilirubin Flashcards
Bilirubin was called
Hematoidin
Bilirubin is the product of what catabolism
Heme catabolism
Who coined the term bilirubin and in what year
Stadeler in 1864
Who discovered bilirubin, what substance in the body, and in what year
Virchow, blood, 1849
This is the “unconjugated” or “indirect” bilirubin
B1
What are the characteristics of B1 bilirubin
FWRB
Found in plasma
Water insoluble
Reacts to Diazo reagent with accelerator
Bound to albumin
This is the “conjugated” or “direct” or “bilirubin diglucu ronide”
B2
Characteristics of B2 bilirubin
Water soluble
Reacts with Diazo reagent and without and accelerator
What bilirubin methods: bilirubin in serum reacts with a diazo reagent forming red-purple azobilirubin at 560nm
Malloy-Evelyn method
At what pH does Malloy-Evelyn method performed
pH of 1.2
Accelerator used in Malloy-Evelyn method
50% methanol
Aliquots used in Jendrassik-Grof method
Aliquot 1- reacted with diazo reagent
Aliquot 2- reacted with diazo reagent and an accelerator
Accelerator used in aliquot 2 in Jendrassik-Grof method
Caffeine-benzoate
Purpose of ascorbic acid in Jendrassik-Grof method
Stops the reaction of the diazo reagent (removes excess diazo reagent)
Components of aliquot 2 of Jendrassik-Grof method
CAA
Caffeine-benzoate (accelerator)
Ascorbic acid (stops diazo reaction)
Alkaline tartrate solution (alkalinizes the solution)
Purpose of alkaline tartrate solution in Jendrassik-Grof method
Alkalinize the solution to shift the absorbance spectrum to lessen or remove interfering substances turning the color to intense blue
At what nm is Jendrassik-Grof method (aliquot 2) measured
598-600nm
Principle of Jendrassik-Grof method
Bilirubin in serum reacts with a diazo reagent forming a purple azobilirubin
Diazo regaent used in Jendrassik-Grof method
Sulfanilic acid in hydrochloric acid and Sodium nitrite
Advantages of Jendrassik-Grof method
NIMMN
Not affected by pH changes
Insensitive to a 50-fold variation in protein concentration of the sample
Maintains optical sensitivity even at low bilirubin concentrations
Minimal turbidity
Not affected by hemoglobin up to 750mg/dL
Enumerate the other liver function tests
liver and serum proteins
Liver enzymes
- Transaminases (alanine aminotransferase and aspartate aminotransferase)
- Alkaline phosphatase
- Y-glutamyl transferase
- 5’-nucleotidase
Serum proteins
PT and aPTT
Specimen collection and storage of bilirubin
Serum or plasma
Avoid hemolysis
Protect from light
List of pathophysiologies of liver
Jaundice (icterus)
Pre-hepatic hyperbilirubinemia
Hepatic jaundice
Post-hepatic jaundice
Describe jaundice (icterus)
Characterized by increased bilirubin in the blood (hyperbilirubinemia) and deposition in the skin, mucous membranes, and sclera