Jaundice

Question 1

Neonatal jaundice
Conjugated
And unconjugated causes

Answer 1

Conjugated increased production of RBC 
Shorter rbc survival 
Higher rbc mass/kg
Decreased metabolism immature liver in neonate
Less hepatitic uptake 
Immature liver enzymes
Enterohepatic circulation 
Decreased gut motility 
Sterile gut

Question 2

HyperBr is defined as

Answer 2

In term infant unconjugated Br >205 mMol/
Preterm infant ** check this level
Conjugated direct >40

Question 3

Jaundice is common

Answer 3

25-50% term babies
85% preterm babies
Kernicterus is rare and preventable
G6PD def is one of the common causes in Australia ( Asian males can be female less likely)

Question 4

UnConjugated Jaundice

Answer 4

Increased production of Br from breakdown
Less conjugation
Increased circulation

Causes
Physiological
Hemolytic
Prolonged

Question 5

Increased production in unconjugated Jaundice causes

Answer 5

Isoimmune hemolysis. ABO incompatibility
Erythrocytes biochem abnormality G6PD def
Abnormal RBC morphology elliptical or spherocytosis
Sequestered blood cephalohaematoma
Polycythemia

Question 6

Decreased conjugation ( unconjugated Jaundice)

Answer 6

Premature infants
Metabolic (Gilberts/ Crigler Najjar )
Endocrine hypothyroidism / child of DM mother / hypopituitarism growth hormone def hypoglycemia/neonatal jaundice

Question 7

Increased enterohepatic circulation

Answer 7

Intestinal atresia
Hirschprungs
Meconium ileus

Question 8

Physiological Jaundice

Answer 8

Appears >24hours ( after day 1 when the baby goes home early)
SBR rise <86mm/l/day ( slow rise)
Peaks day 3-5 NOT >258mm/l
Resolves by 1/52 in term infants and 2/52 in a preterm infant

Question 9

Early onset BF Jaundice

Answer 9

5-10% of newborn Jaundice

Insuff production or intake of Breast milk

Question 10

Late onset Breast milk Jaundice

Answer 10

Diagnosis of exclusion
Starts 4-7 days max day 6-14days
Persists beyond physiological Jaundice
May remain raised Br 1-3/12 of age

Question 11

G6PD def

Answer 11

Enzyme in the RBC
Provides NADPH which is a buffer agains oxidative stress
Commonest cause of RBC enzyme def
Sex linked so MALES effected commonly ( but can seen in Females)
Thought to protect against Malaria
Common in Asian families and napthaline can ppt a crisis

Question 12

Causes of Conjugated Jaundice

Answer 12

1 Hepatitis
2 Biliary atresia (clay colored stools/dark urine) DISIDA scan
3 biliary obstruction eg cholodocal cyst USS of abdomen
4 Alpha 1 AT def
5 TPN cholestatsis seen in PICU

Question 13

Approach to prolonged Jaundice

Answer 13

Exclude obstruction biliary atresia or choledocal cyst
Hypothyroidism
Infection Urine
If not breast fed or is high Br Ix further

Question 14

Kernicterus

Answer 14

Br staining of the neurons and neuronal necrosis affecting the basal ganglia hippocampus and the subthal nucliea
Free unconjugated br crosses the BBB ( if its linked to Albumin too big and cannot cross the BBB)
PPT at low ph and toxic to neurons
Causes cell death

Question 15

Clinical presentation of Kernicterus

Answer 15

Acute low tone poor suck t
Then get hypertonic fevers and seizures
Then hypotonia

Chronic
Hypotonic Extrapyrmaidal side effects
CP, deaf, effects congnition

Question 16

Which babies are at risk of Kernicterus

Answer 16

Preterm infants (BBB more permeable)
Low Albumin ( if high Al binds the Br and its too big to cross the BBB)
Rapid rise in Br level
Hypoxia/ Acidisos/Sepsis/Hypoglycemia
Infections such as TRCH toxoplasmosis, rubella, CMV,Herpes

Question 17

Maternal factors effect Kernicterus

Answer 17

Blood group

DM ( increased risk of polycythemia)

Question 18

At risk Neonates for Kernicterus

Answer 18

Jaundice within 24hours
Previous J in a sibling
Gestation 35-38weeks ( younger you are the >risk)
Exclusive BF
Asian G6PD def ( napthaine balls )
Cehpalheamatoma/bruising
Males

Question 19

Investigations for Jaundice

Answer 19

SBR fractions ( conj/unconjugated)
Haemolysis FBC and film look at RBC morphology
Infections UTI Blood cultures
Metabolic

Question 20

Treatment of Jaundice

Answer 20

Aim is to prevent Kernicterus

Question 21

Treatment of Jaundice

Answer 21

Aim is to prevent Kernicterus 
Phototherapy 
Albumin
Iv immunoglobulin 
Exchange transfusion

Question 22

Phototherapy

Answer 22

450-460nm light  (blue not ultraviolet light)
Indications for it 
rh disease
Other haemolytic disease
Small sick infants 
Safe and effective  ( blue light is the most effective)
CEASE photo therapy when the SBR falls 25-50 mMol/l below the threshold 
Monitor for 
Hypo/hyperthermia 
Dehydration
Eye damage 
Rashes 
Diarrhea

Question 23

When to start phototherapy

Answer 23

There are specific nomograms to assist at the risk for hyperBr and when to use phototherapy based on age and level of Br

Question 24

IV immunoglobulin

Answer 24

Used with phototherapy to treated Jaundice been shown to reduce the need for exchange transfusion
Been shown to reduce the sr Br level

Question 25

Albumin

Answer 25

If low sr albumin it has been shown that this binds the Br and reduces the risk of Kernicterus

Question 26

Exchange transfusion uses

Answer 26

1 ABO or other blood grp incompatibility if Br >340 2 preterm infant /infant of DM mother Br>340 3consider exchange transfusion for Rh sensation with +ve Coombs test Oedema/peticha /HSM / rapidly developing Jaundice Maternal anti Rh titre >/=1:64 Indirect Br >340 Conjugated Br >90

Question 27

What does exchange transfusion do?

Answer 27

``` 1 removes unconjugated Br Ab coated RBC Ab again RBC antigen 2 provides durable RBC 3 does not remove tissue Br ( not from the skin so need to keep photo therapy going after exchange transfusion can get rebound J) ```

Question 28

Kramers rule

Answer 28

``` Face/head 100 Chest and 1 150 Abdomen and 1/200 Legs 250 Feet and hand >250 Not reliable ```

Question 29

Weight loss in a Jaundiced baby

Answer 29

Weight loss in BR babies can be 10% from birth Median loss 6.6% in a term BF baby Median loss 3.5% in a term bottle fed baby Breast fed Jaundice <290