Lecture 5 - Pediatric GI

Question 1

Which type of bilirubin is toxic to the CNS? (Be specific!)

Answer 1

FREE (not bound to albumin); UNCONJUGATED bilirubin

Question 2

The large amounts of unconjugated bilirubin in the blood of a new baby is due to what factors?

Answer 2

• Due to hemolysis
• Due to inadequate conjugation and clearance

Question 3

What is the most common cause of unconjugated hyperbilirubinemia in an infant?

Answer 3

Hemolysis of RBC’s

Question 4

Differentiate breast feeding jaundice vs. breast milk jaundice?

Answer 4

• Breast feeding jaundice is more of a function of dehydration and decreased excretion of bilirubin in the stool (related to the supply of the breast milk, which is sometimes low in first few days)
• Breast milk jaundice is due to presence of deconjugating enzymes in milk

Question 5

Which type of hyperbilirubinemia is never non-pathologic?

Answer 5

Conjugated

Question 6

What is Rh and why should Rh testing be done on all pregnant women?

Answer 6

• Rh is inherited and found on surface of RBC’s
• If mom is Rh (-) and baby is Rh (+) –> some of babies RBC’s get into Mom’s circulation during pregnancy and Mom develops Rh antibodies
• No big deal in 1st pregnancy, but w/ subsequent pregnancies the Rh antibodies can cross placenta and wreak havoc on Rh (+) baby (hydrops fetalis or erythroblastosis fetalis)

Question 7

If Mom is blood type O or if Mom is Rh negative, the infant’s cord blood should be evaluated for what 3 things/how?

Answer 7

1. A direct antibody (Coomb’s) test = DAT
2. Blood type
3. Rh determination

Question 8

If a newborn has conjugated hyperbilirubinemia in the first few post-natal weeks what is the first thing you should think?

Answer 8

Biliary atresia/cholestasis

Question 9

What is seen in Phase 1 (the first 1-2 days) of acute bilirubin toxicity in an infant (w/ high unconjugated bilirubinemia)?

Answer 9

• Poor suck
• High pitched cry
• Stupor
• Hypotonia
• Seizures

Question 10

What is seen in Phase 2 (middle of first week of life) of acute bilirubin toxicity in an infant (w/ high unconjugated bilirubinemia)?

Answer 10

• Hypertonia of extensor ms.
• Opisthotonus
• Retrocollis
• Fever

Question 11

What is seen in Phase 3 (after first week of life) of acute bilirubin toxicity in an infant (w/ high unconjugated bilirubinemia)?

Answer 11

Hypertonia

Question 12

What is the chronic and permanent sequelae of Bilirubin Induced Neurologic Dysfunction (BIND)?

Answer 12

Kernicterus

Question 13

What are some of the main signs of Kernicterus in a newborn?

Answer 13

• Choreoathetotic movements
• Ballismus
• Upward gaze
• Dental dysplasia

Question 14

If there is jaundice in the first 24 hrs or the jaundice is excessive for infants age; which tests should be run?

When should Total Serum Bilirubin (TSB) be rechecked?

Answer 14

1) Bloody type and Direct Antibody (Coomb’s) test
2) CBC and peripheral blood smear
3) Conjugated bili level
4) Reticulocyte count
- Repeat TSB in 4 hours

Question 15

If there is prolonged jaundice in an infant and you are approaching 2 months, what should you start thinking about?

Answer 15

Gilbert’s

Question 16

What are 3 signs/symptoms of Biliary Atresia in an infant?

Answer 16

• Cholestatic jaundice (conjugated hyperbilirubinemia)
• Hepatomegaly
• Acholic stools

Question 17

Extrahepatic biliary atresia occurs where in the hepatobilirary system?

Answer 17

Common bile duct

Question 18

Crigler-Najjar Type 1 and Type 2 differ in their response to what drug?

Answer 18

• Type 1 has NO bilirubin decrease w/ phenobarbital
• Type 2 the bilirubin levels will decrease with phenobarbital

Question 19

Which clinical test is the most definitive way of determining if someone is having clinically significant reflux?

Answer 19

• Esophageal pH monitoring w/ multichannel intraluminal impedance testing (MII)
• Measures frequency of GER and association of low esophageal pH w/ sx’s

Question 20

Surgery as a treatment for GERD in a child should only be considered after what has been done first?

More commonly done in which children?

Usually only done if the GERD is severe enough to cause?

Answer 20

• pH /MII esophageal study has been completed
• More common in developmentally delayed childre
• Only if GERD is putting the child’s nutrition or respiratory status at risk

Question 21

What is the most common location for intussusception in infancy?

Answer 21

• ileocolic
• Ileum invaginates into colon at the ileocecal valve/junction

Question 22

What is the consistency of the stools associated with intussusception?

Answer 22

• Bright red blood and mucous
• “Currant jelly stools”

Question 23

Which other symptom is often times seen intermittently in children with intussusception?

Answer 23

Striking lethargy is present intermittently

Question 24

2 types of treatment for Intussuception?

Answer 24

• Hydrostatic reduction w/ a contrast enema (less common)
• Pneumatic reduction with an AIR enema

Question 25

What are the 3 classic metabolic findings associated with Pyloric Stenosis?

Answer 25

- **Hypo**chloremic - **Hypo**kalemic - **Metabolic alkalosis** \*Due to all the **vomiting!**

Question 26

What are 4 pathologic abnormalities resulting in **increased production** unconjugated bilirubin in a new born?

Answer 26

1. Erythrocyte-enzyme deficiencies 2. Blood group incompatibility (ABO) 3. Structural defects in RBC's 4. G6PD deficiency (enzyme deficiency)