Neonatal Jaundice

Question 1

What can high levels of bilirubin can result in permanent brain damage.
What is the medical term?
Where does it deposit and what is the main sequelae of this?

Answer 1

Kernicterus
When the bilirubin that is binded to albumin is saturated (conjugated), unconjugated bilirubin, which is insoluble in water and soluble in lipids, crosses the BBB and deposits into the basal ganglia causing

Choreoathetoid cerebral palsy (dyskinetic)
hypotonia
seizures
semi-comatose
high pitch/weak cry

Question 2

What is the tetrad of chronic sequelae of bilirubin encephalopathy or Kernicterus

Answer 2

1) Motor: Motor delay and Choreoathenoid cerebral palsy
2) Oculo-motor: Upward gaze
3) Cochlear: Sensorineural deafness
4) Intellectual: mild cognitive impairment

Question 3

Neonatal hyperbilirubinemia or jaundice is the Yellow discoloration of the skin, sclera and mucous membranes due to accumulation of bilirubin in extravascular tissue. State the causes of Jaundice in neonates

Answer 3

1) Excessive RBC destruction (immune-mediated hemolysis, Polycythemia, RBC structural defects)
2) Sepsis and drugs
3) Decreased conjugation (prematurity, Gilbert’s syndrome - enzyme defects)
4) Decreased elimination (liver hypo perfusion, biliary obstruction, sepsis, intestinal obstruction)
5) Breast milk jaundice

Question 4

What is the main cause of immune-related hemolysis in the newborn?

Answer 4

blood group mismatch
rhesus disease

Question 5

What is the pathophysiology of jaundice starting from the breakdown of an RBC including how it affects the brain, re-uptake by gut, pee and poo.

Answer 5

The breakdown product of haemoglobin is unconjugated bilirubin (indirect bilirubin), which is insoluble in water but soluble in lipids. It is carried in the blood bound to albumin. When the albumin binding is saturated, free unconjugated bilirubin can cross the blood–brain barrier, as it is lipid soluble. Unconjugated bilirubin, previously bound to albumin, is taken up by the liver and conjugated by glucuronyl transferase to conjugated bilirubin (direct bilirubin), which is water soluble and excreted in bile into the gut and then as stercobilinogen and urobilinogen. Some bilirubin in the gut is converted to unconjugated bilirubin and reabsorbed via the enterohepatic circulation to and metabolized in the liver or excreted in urine giving dark urine

Question 6

you are called into review a jaundiced neonate <24 hours of age, what is your suspected cause? (2)

Answer 6

Congenital infection
Hemolytic disorder (Rh, ABO, G6PD)

Question 7

you are called into review a jaundiced neonate <2 weeks of age, what is your suspected cause? (4)

Answer 7

Breast milk jaundice
Infection (e.g. UTI)
Polycythemia
Hemolytic disorder (Rh, ABO, G6PD)

Question 8

you are called into review a jaundiced neonate >2 weeks of age and is producing a very dark urine and pale stools. what is your suspected cause?

Answer 8

conjugated disease
Bile obstruction e.g. billiary atresia
Neonatal hepatitis

Question 9

you are called into review a jaundiced neonate >2 weeks of age and is producing normal urine color what is your suspected cause?

Answer 9

Breast milk jaundice
Infection
Hypothyroidism
High GI obstruction (e.g. pyloric stenosis)
Hemolytic anemia (Rh, ABO, G6PD)

Question 10

What is meant by “direct” bilirubin level?

Answer 10

The amount of conjugated bilirubin

Question 11

Jaundice <24 hours is always considered to be…

Answer 11

Pathological and needs urgent investigation and close monitoring.

Question 12

Physiological jaundice typically occurs between 2-5 days after birth.
What is physiological jaundice?
Is it typically conjugated or unconjugated?
Do they typically have neurological sequalae?

Answer 12

Infants have more rbcs (high hematocrit) of lower lifespan and an immature hepatic and elimination pathway => harder to clear also (+bruising during delivery). This will cause a transient buildup of broken down rbcs => more bilirubin.
It is typically unconjugated (indirect)
No neurological sequalae

Question 13

What are the main causes of pathological jaundice?
When do these most likely occur?
Is it typically conjugated or unconjugated?
Is it typically prolonged or short term elevation in bilirubin levels?

Answer 13

Pathological until proven otherwise if <24 hrs. These are usually due to severe hemolysis (Rh, ABO, G6PD) where IgG antibodies are produced or congenital infection (TORCH)
Typically unconjugated
Typically prolonged (>14 days)

Question 14

Give 3 ways to find how much bilirubin is present?

Answer 14

bilimeter - transcutaneous bilirubin
SBR - Serum bilirubin conjugated and unconjugated
DCT - Direct Coombe’s Test

Question 15

What main parts of the history that are significant for jaundice in an otherwise normal newborn (no congenital heart defects etc..) ?

Answer 15

Family hx of jaundice, anemia, splenectomy, G6PD
Ethnicity
Must know! Ongoing hemolysis (mom and baby ABO and RH status)
Feeding and voiding history (all the details)

Question 16

What is the typical scenario of rhesus disease? Mom is Rh? Baby is Rh?. What will happen on exposure

Answer 16

Typically it is a RhD -ve women carrying a RhD +ve fetus. On exposure (typically secondary to feto-maternal hemorrhage), the IgG antibodies of the mother will cross at attach to rbcs of the fetus => hemolysis

Question 17

Every subsequent pregnancy is worse due to increasing levels of IgG with each exposure. What is a major complications to the fetus in mothers exposed to a Rh+ve fetus?

Answer 17

Erythroblastosis fetalis/fetal hydrops

Question 18

How would you prevent Hemolytic anemia of the newborn?

Answer 18

Screen for Rh -ve mothers via serology for D IgG antibodies (3rd trimester).
Prevent sensitization: If Rh-ve, give Anti-D immunoglobulin IM after delivery or miscarriage

Question 19

Fetal Hydrops (Erythroblastosis fetalis)
What are the clinical signs?
What investigations would you perform?
How would you manage a baby with acute onset jaundice postpartum?

Answer 19

Clinical signs:
Severe early onset jaundice
Hepatosplenomegaly
Heart failure (oedema and !ascites!)
Hemolytic anemia

Investigation:
Bilirubin levels: SBR conjugated and unconjugated, DCT
Mother and fetus/baby ABO and Rh status (2 separate tests)
Bloods: Reticulocytotic (best indicator of new rbc production => indicates hemolytic anemia)
Other bloods to always to: TFTs, blood glucose, LFTs

Management:
ABCD!!! and resuscitation
Check cord bloods
Transfer to NICU and conduct serial bilirubin measurements (to track if management is working (decline) or not)
IVIG
!Phototherapy!
Exchange transfusion not carried out but is an option

Note: Same workup for ABO and G6PD deficiency but much milder disease => assess need for resus.

Question 20

Dx: Mild, early onset unconjugated jaundice
Moderate/severe, early onset unconjugated jaundice

How would you treat any of these if they were otherwise found antenatally

Moderate, late onset conjugated jaundice
How might you diagnose this?

Answer 20

1) Hemolytic anemia due to ABO or G6PD deficiency
No indication antenatally
2) Hemolytic anemia of the newborn
Anti-D immunoglobulin
3) Biliary atresia or neonatal hepatitis
HIDA scan (Hepatobiliary iminodiacetic acid) imaging

Question 21

Polycythemia is a cause of jaundice. What is considered polycythemia in the first week of life?

Answer 21

Hematocrit >65%

Question 22

An infant of a diabetic mother is born with reddish pinkish skin and a non-dilated abdomen. What is your likely diagnosis? What are other causes of this?

Answer 22

Polycythemia (note the abdomen is not distended but can be as this is a cause of nec enterocolitis)

Other causes: Chronic intrauterine hypoxia (the compensation of that after birth is what causes polycythemia)
Also delayed cord clamping

Question 23

What are clinical features of polycythemia. How would you manage this patient if symptomatic?

Answer 23

Clinical:
Neurological (lethargy, jittery)
Cardioresp (transient tachypnea of the newbown)
GIT (Hypoglycemia (diabetic mother RF), jaundice, necrotizing enterocolitis)

Question 24

How would you judge bilirubin levels in a neonate?
AKA what factors influence normal bilirubin levels

Answer 24

Hour of life
Gestation
Rate of rise
taking into account physiological factors of brain entry, excessive production and diminished excretion

Question 25

What are the measures you may want to employ to prevent jaundice in the newborn? (2)

Answer 25

Anti D immunoglobulin (If scan verifies RhD -ve)
Early and frequent feeding to decrease enterohepatic circulation and increase bilirubin excretion in stool

Question 26

What is the very general treatment of jaundice in the neonate?

Answer 26

Ensure adequate hydration
Phototherapy (conjugates bilirubin for the liver)
IVIG therapy

Question 27

Seizures + jaundice. What do you give?

Answer 27

Phenobarbitone

Question 28

Is phototherapy used for conjugated or unconjugated jaundice and why? What might happen if the other option was done?

What are some side effects of phototherapy? (2)

Answer 28

Phototherapy is used in unconjugated jaundice as it conjugated bilirubin instead of the liver and hence assisting with excretion from the system (conjugated is water soluble). If it was given to a conjugated jaundice patient, it may cause Bronze Baby Syndrome => never give it to a baby with dark urine or pale stools

Dehydration (ensure hydration!!)
Hyperthermia
decreased time spent with mother

Question 29

A colleague suggests exchange transfusion for a jaundiced child.
What is it? What is meant by double transfusion
When is it most beneficial?
What are the risks?

Answer 29

Small amounts of neonate’s blood is replaced with donor blood. If double, => double of the baby’s volume is replaced.
It is most beneficial in cases of ongoing hemolysis (partial use in polycythemia)
Risks: Portal vein thrombosis => thrombocytopenia, graft vs host disease, Nec ent, infection…

Question 30

Breast milk jaundice is a diagnosis of exclusion. They typically present 2-3 weeks later and are otherwise completely healthy.
Why does breast milk cause jaundice?
What treatment is required?

Answer 30

Breast milk causes jaundice as some contituents may inhibit conjugation in the liver.
No treatment is required as it usually regresses by 3 months. If severe maybe suggest mixed formula/breast milk or switching to formula. If you wanna be safe just say refer to lactation consultant

Question 31

Delayed presentation of jaundice with acholic stools:
What is acholic stools
What is the most likely diagnosis?
How can you prove it?
What treatment is required?

Delayed presentation of jaundice with pale stools:
What is the most likely diagnosis?
What can cause this?

Answer 31

Acholic stools are completely white and not just paler
dx: biliary atresia
HIDA scan (Hepatobiliary iminodiacetic acid) imaging
Tx: Kasai procedure

Neonatal hepatitis
Infections or metabolic causes such as alpha-1 antitrypsin deficiency

Question 32

What is the most common form of biliary atresia?

Answer 32

Extrahepatic

Question 33

A 3 week baby presents to you with a fever and jaundice. You suspect an infection. What infection are you suspecting (type, not organism)

What if the baby didnt have a fever? What would you be suspecting?

Answer 33

UTI

No fever? Breastfed? If so probably breast milk jaundice. If not, congenital hypothyroidism