What is it called when pigment bilirubin builds up in the brain, causing damage?
What is an ultimate adverse effect of kernicterus in infantcy?
athetoid CP (uncontrolled movement of face, body, amrs, and legs)
What is the correct terminology for scleral icterus?
Conjunctival icterus (which is the membrane covering the sclera)
Which form of bilirubin is water solubable?
What form of bilirubin is lipid-soluble?
Which type of bilirubin builds up in the brain, leading to kernicterus?
Unconjugated because it is lipid-soluable and able to cross the B-B-B.
Where is unconjugated bilirubin converted to bilirubin?
How is bilirubin produced? (2 processes)
1. breakdown of RBC
2. breakdown of other heme proteins (10%)
What enzyme breaks down the heme?
Enzyme heme oxygenase (HO), located in the spleen and liver
Bilirubin is the byproduct of what?
Biliverdin (results from breakdown of heme)--> converts to bilirubin with biliverdin reductase
Discuss the process of unconjugated bilirubin.
Biliverdin--> unconjugated bilirubin--> binds w/ albumin & transported to liver--> dissociates and enters hepatocyte--> conjugated into H20-soluable--> secreted into bile--> eliminated in the intestines
T or F. Conjugated bilirubin can be excreted both renally and hepatically.
What enzyme can unconjugate bilirubin to be reabsorbed into circulation?
What are 4 ways that conjugated bilirubin can build up?
1. Decrease excretion
2. Liver dysfunction
3. gall bladder disorder
4. portal system dysfunction
What 3 things can effect the amount of free bilirubin in the body?
1. Binding capacity of albumin
2. affinity of tissue
3. pH of blood
What are 5 causes of unconjugated/indirect bilirubin buildup?
1. hemolysis condition
2. decreased hepatic uptake
3. decreased conjucation
4. impaired hepatic secretion
5. biliary obstruction
What are 4 clinical results of Indirect Hyperbilirubenemia?
1. Physiologic jaundice
2. Ciglar-Najjar syndrome
3. Breast milk jaundice
4. jaundice 1st day of life
What are the 3 main causes of Indirect Hyperbilirubinemia?
2. Impaired hepatic uptake
3. Decreased conjugation
What are the 2 major causes of Direct Hyperbilirubinemia?
1. Defect in excretion of bilirubin from hepatocyte into the bile
2. mechanical obstruction of the bile
What are 4 common causes of Direct Hyperbilirubinemia?
1. Infection (CMV) & sepsis
2. Neonatal hepatitis
4. bilirubin displacing drugs (sulfa)
What is a symptom of biliary atresia and what type of Hyperbilirubinemia is it?
-Dark urine & gray-white stool
What is the 2nd most come cause of hyperbilirubinemia?
**Increased bilirubin production (breakdown of RBCs secondary to hemolysis/nonhemolysis)
What are some causes of hyperbilirubinemia when associated with NON-hemolysis?