Jaundice in the neonatal period

Question 1

Causes of unconjugated hyperbilirubinemia

Answer 1

1) Hemolytic
a) Intrinsic
- Membrane: spherocytosis, elliptocytsis
- Enzyme:G6PD, PK deficiency
- Hb: thalassemia
b) Extrinsic
- ABO, Rh incompatibility
- Splenomegaly
- Sepsis
- AV malformation

2) Non-hemolytic
- Hematoma
- Polycythemia
- Sepsis
- Hypothyroidism
- Gilbert
- Crigler-Najjar

3) Physiologic

Question 2

Causes of conjugated hyperbilirubinemia

Answer 2

1) Hepatic
a) Infectious- Hep A, B, C, Sepsis, TORCH
b) Metabolic- Galactosemia, tyrosinemia, A1AT, Hypothyroid, CF
c) Drugs
d) TPN
e) Idiopathic neonatal hepatitis

2) Post hepatic
- Biliary atresia
- Choledochal cyst

Question 3

Important history

Answer 3

Baby unwell- sepsis? bowel obstruction?
Dehydration, poor weight gain- can exacerbate
serology, viral
FHx of hemolysis
Dark urine, pale stools
Plethora
Hepatosplenomegaly->metabolic, viral

Question 4

Investigations in unwell child/febrile

Answer 4

Septic screen
FBE/CRP/BC
UEC/LFT/VBG/Glucose
IV antibiotics
Bilirubin
Blood film/Reticulocytes
Blood group/Coombs

Question 5

Investigations in well, afebrile

Answer 5

FBE
Bilirubin
Blood film/Reticulocytes
Blood group/Coombs

Question 6

Investigations if conjugated bilirubin >15%

Answer 6

LFTs
Clotting
TFTs
Septic screen
Viral serology
A1AT levels
Abdominal USS
DW gastroenterology

Question 7

Investigations when evidence of hemolysis

Answer 7

DW haematologist

Question 8

Investigations when total in treatable range

Answer 8

NNU consultations
Urine MCS/reducible
UEC
G6PD
TFTs

Question 9

Investigations when prolonged, and what is considered prolonged w/o an obvious cause

Answer 9

Prolonged is >2 weeks in full term and >3 weeks in preterm
DW paediatric senior
Urine MCS/reducing substrates
TFTs
G6PD
Arrange follow up

Question 10

What are reducing substances

Answer 10

Galactose
Fructose
Glucose

Question 11

Glycosuria -ve, but + urine for reducing substances, management

Answer 11

Further testing required

Remove lactose immediately from diet, pending results of further investigations

Question 12

Discharge instructions for unconjugated hyperbilirubinemia

Answer 12

Sunlight is not treatment
Early F/U with GP
Ensure adequate oral intakes, especially

Question 13

Phototherapy- hydration, monitoring, rechecking bilirubin

Answer 13

++Attention to fluid intake and hydration
Correct hydration over at least 24 hours
Check bilirubin after 6 hours starting therapy

Question 14

What level of bilirubin rise should warrant call to NNU

Answer 14

If rate of rise >10micromol/L/hour

Question 15

Final option for treatment if supportive and phototherapy no longer appropriate

Answer 15

Exchange transfusion

Question 16

Important examination

Answer 16

Extent of the jaundice
Congenital viral infection->petechiae, anemia, hepatosplenomegaly
Dehydration
Well
Evidence of infection
Examine the stool

Question 17

Why is checking clotting and vitamin K levels important

Answer 17

Prolonged jaundice can +risk of bleeding disorders associated with vitamin K deficiency

Question 18

Wavelength of phototherapy

Answer 18

450nm

Question 19

Commonest cause of jaundice in an older child

Answer 19

Hepatitis A

Question 20

Other causes of jaundice in older children

Answer 20

Chronic hemolysis->spherocytosis, G6PD
Autoimmune chronic hepatitis
Reyes syndrome
Paracetamol overdose
Wilson's
Gilberts
Cigglar-Najar

Question 21

When does physiological jaundice occur, and when does it resolve

Answer 21

Occurs on day 2-3, usually resolves in 7 days

Question 22

Pathophysiology of physiological jaundice (3)

Answer 22

1) +Hct and reduced RBC lifespan
2) Immature conjugating system
3) Increased enterohepatic circulation

Question 23

Risk factors for jaundice: maternal, perinatal, neonatal

Answer 23

Maternal:
Ethnic group
Complications->diabetes
Rh/ABO incompatibility

Perinatal:
Birth trauma
Prematurity

Neonatal factors:
Difficulty establishing breathing
Infection
Genetics
Polycythemia
Drugs

Question 24

Causes of jaundice

Question 25

Causes of jaundice 24-72

Answer 25

``` 24-72 h Physiologic, polycythemia Dehydration (breastfeeding jaundice) Hemolysis G6PD deficiency Pyruvate kinase deficiency Spherocytosis Bruising, hemorrhage, hematoma Sepsis/congenital infection ```

Question 26

Causes of jaundice 72-96

Answer 26

``` 72-96 h Physiologic ± breastfeeding Sepsis Prolonged Breast milk jaundice ```

Question 27

Causes of prolonged

Answer 27

``` Breast milk jaundice Prolonged physiologic jaundice in preterm Hypothyroidism Neonatal hepatitis Conjugation dysfunction e.g. Gilbert syndrome, Crigler-Najjar syndrome Inborn errors of metabolism e.g. galactosemia Biliary tract obstruction e.g. biliary atresia ```

Question 28

Differentiate breastfeeding jaundice vs breast milk jaundice

Answer 28

Breastfeeding jaundice if when reduced breast milk production->dehydration->exagerated physiologic jaundice Breast milk jaundice: glucuronyl transferase inhibitor found in breast milK, onset day 7, persists for several weeks and resolves by 6 weeks. If not reason to cease breastfeeding

Question 29

Red flags for pathalogical

Answer 29

1-2 weeks of age

Question 30

Hemolytic work up

Answer 30

``` CBC Reticulocyte Blood group Blood smear Coombs test Bilirubin ```

Question 31

How does phototherapy work

Answer 31

Insoluble unconjugated bilirubin is converted to excretable form via photoisomerisation

Question 32

Can you perform phototherapy in conjugated hyperbilirubinemia, why

Answer 32

No | Results in bronzed baby

Question 33

Etiology of kernicterus

Answer 33

Unconjugated bilirubin levels ++ than binding capacity of albumin->deposit in brain stem and basal ganglia

Question 34

What level of bilirubin= risk of kernicterus

Answer 34

When levels >340umol/L

Question 35

When can kernicterus occur at lower levels than

Answer 35

sepsis, meningitis, hemolysis, hypoxia, acidosis, | hypothermia, hypoglycemia and prematurity

Question 36

Clinical presentations: early (4), mid (6), late stage (6)

Answer 36

Early: hypotonia, lethargic, poor feeding, emesis Mid: hypertonic, high pitched cry, opisthotonic posturing (back archign), bulging fontanelles, seizures and pulmonary hemorrhage. Late (beyond a year): hypotonia, EPS (choreoathetoid cerebral palsy), gaze palsy, mitral regurgitation, sensorineural hearing loss.

Question 37

Long term complications of kernicterus

Answer 37

Sensorineural deafness Choreoathetoid cerebral palsy Gaze palsy Mental retardation

Question 38

What is biliary atresia and how does it present

Answer 38

``` Atresia of extrahepatic bile ducts->cholestasis, +conjugated bilirubin Dark urine, pale stool Jaundice persisting for >2 weeks Abdominal distension hepatomegaly ```

Question 39

Diagnosis of biliary atresia- investigations

Answer 39

Conjugated hyperbilirubinemia, abdominal USS HIDA san Liver biopsy

Question 40

Treatment of biliary atresia

Answer 40

* surgical drainage procedure | * hepatoportoenterostomy (Kasai procedure; most successful if