Clipp 8: Neonatal Jaundice

Question 1

Why are newborns often jaundiced?

Answer 1

Newborns lack the GI flora that normally metabolizes bile to be excreted in the stool.

Beta-glucuronidase present in newborn meconium hydrolyzes the conjugated bilirubin back to its unconjugated form which is reabsorbed into the blood stream (enterohepatic circulation)

Question 2

How does indirect bilirubin affect the brain?

Answer 2

Kernicterus, neurologic impairment, brain damage, or encephalopathy

Question 3

Signs and symptoms of kernicterus?

Answer 3

Kernicterus results in abnormalities in tone and reflexes, choreoathetosis, tremor, oculomotor paralysis, sensorineural hearing loss and cognitive impairment.

Question 4

Define physiologic jaundice

Answer 4

a total bilirubin level ≤ 15 mg/dL (≤ 257 μmol/L) in full-term infants who are otherwise healthy and have no other demonstrable cause for elevated bilirubin.

Question 5

Why does low feeding lead in to increased jaundince?

Answer 5

slow excretion of meconium

Question 6

Describe breast feeding jaundince

Answer 6

Low intake leads to slow excretion of meconium and The β-glucuronidase in meconium deconjugates bilirubin and the unconjugated bilirubin is reabsorbed via the enterohepatic circulation, causing an elevation of serum levels.

Question 7

Main differentiation between breast feeding and breast milk jaundince?

Answer 7

Timing

Breast feeding appears early and stops when meconium passes

Breast milk begins around day 4-7, peaks around day 10, and may persist 12 weeks outs

Question 8

Major causes of hemolysis in newborns?

Answer 8

Rh incompatibility (although no longer)
ABO incompatibility
RBC membrane defects (spherocytosis)
Blood cell enzyme defects (pyruvate kinase deficienc,y, G6PD)

Question 9

Non-hemolytic causes of RBC breakdown?

Answer 9

Extensive bruising from birth trauma
Large cephalohematoma or other hemorrhage (e.g., intracranial)
Polycythemia
Swallowed blood (large amounts) during delivery.

Question 10

Two genetic diseases causing unconjugated hyperbilirubinemia?

Answer 10

Criglar-Najar

Gilbert’s

Question 11

TWo genetic diseases causing conjugated hyperbilirubinemia?

Answer 11

Rotors

Dubin-Johnson

Question 12

Two systemic pathologies that may cause hyperbilirubinemia?

Answer 12

Sepsis

Metabolic acidosis

Question 13

A healthy-appearing infant who develops jaundice, dark urine, and acholic (pale) stools between 3 and 6 weeks of age may have…..

Answer 13

Biliary Atresia

Question 14

Any infant who develops jaundice after two weeks of age must be evaluated with…..

Answer 14

Fractionated bilirubin

Question 15

What supplement is recommended for exclusively breastfed babies <6 months?

Answer 15

Vitamin D

Question 16

Differentiate cephalohematoma from caput succedaneum

Answer 16

A caput succedaneum is an edematous swelling over the presenting portion of the scalp of an infant

Cephalohematoma is a subperiosteal hemorrhage that is localized to the cranial bone that was traumatized during delivery. The swelling does not extend across a suture line

Question 17

When does jaundice from biliary atresia develop?

Answer 17

3-6 weeks

Question 18

When does jaundice from ABO incompatibilty develop?

Answer 18

w/in the 24 hours of life