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 Post subject: Neonatal Jaundice
PostPosted: 25 Dec 2017 13:16 
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Description: Jaundice occurring in the newborn (neonatal jaundice) is common, usually harmless and resolves by itself. In some cases, it may be indicate serious underlying disease

What is Neonatal Jaundice?
Jaundice occurring in the newborn is referred to as neonatal jaundice. It is quite common, usually harmless and resolves in two weeks. It is characterized by yellowish discoloration of the skin and eyes.

Approximately 60% of term babies and 80% of preterm babies develop jaundice. It will disappear spontaneously within a week or two, but in some cases it will be more severe and prolonged, needing further investigations and aggressive treatment.

How is Jaundice Caused – Bilirubin Formation and Excretion
Jaundice is not a disease per se but a symptom of an underlying disease. The yellowish discoloration of the skin and eyes is due to deposition of a pigment called bilirubin which accumulates in the bloodstream due to various causes.

One of the important sources of bilirubin in the body is when red cells breakdown due to aging and senescence and are replaced by new red cells from the bone marrow. The bilirubin from red cell breakdown is conjugated in the liver and then excreted.

What is Physiological Jaundice?
• The most common cause of neonatal jaundice is physiological jaundice.
• This occurs because newborns have more red cells than adults and a higher rate of breakdown.
• Additionally the newborn liver is immature and unable to handle the increased amounts of bilirubin being formed.
• This results in accumulation of bilirubin in the blood with symptoms of jaundice.

The physiological jaundice described above usually presents between day 2 – 4 after birth, peaks at one week and gradually resolves spontaneously in about two weeks.

What is Pathological Jaundice?
In some cases however, jaundice caused due to some serious underlying disease of the blood or liver. This is termed pathological jaundice.

Pathological jaundice shows the following characteristics
• It appears on the first day of life itself
• Bilirubin levels in the blood may be very high with severe jaundice
• Baby is ill and does not feed well and appears irritable
• Jaundice is still present even after two weeks (prolonged jaundice); the baby passes pale chalky appearing stools (due to absence of bilirubin in the stool) and dark colored urine (due to increased bilirubin pigment)
• Enlarged liver and spleen, small head size (microcephaly) seen in some congenital infections

It is important to recognise and treat jaundice in the neonate promptly because high bilirubin
levels in the bloodstream (hyperbilirubinemia) can be deposited in and damage the brain (kernicterus).

What are the Causes of Pathological Jaundice?
Some of the commonly seen causes of pathological jaundice include the following

Increased red cell breakdown/hemolysis - ABO or Rh incompatibility between mother’s and baby’s blood groups, hereditary spherocytosis, Glucose-6-phosphate dehydrogenase (G6PD) deficiency

Neonatal infections – Toxoplasmosis, rubella, cytomegalovirus (CMV), herpes simplex, syphilis

Inherited disorders of bilirubin metabolism – Criggler Najjar syndrome, Dubin Johnson syndrome, Gilbert syndrome

• Other uncommon causes include biliary atresia and metabolic diseases such as aminoacidurias, galactosemia, and alpha-1 antitrypsin deficiency

What are the risk factors of developing Neonatal jaundice?
• Preterm or low birth weight babies
• Male babies
• East Asian ancestry
• Breastfed babies
• Sibling who had neonatal jaundice
• Babies born to diabetic mothers
• Populations living at high altitudes

How is Neonatal Jaundice Diagnosed?
Neonatal jaundice is usually evident on physical examination. However, it may be difficult to discern on darker skin and when there is an index of suspicion, a blood test is done to measure bilirubin levels.

Some centres initially measure bilirubin using a device that measures bilirubin levels through the skin (transcutaneous screening). When the bilirubin value on transcutaneous measurement exceeds a certain value (250 micromol/L), blood testing may be done to measure bilirubin levels and confirm the diagnosis. Serum bilirubin level measurements include total bilirubin, giving levels of conjugated and unconjugated bilirubin as well.

Typically, in hemolytic conditions and disorders of bilirubin conjugation by liver, unconjugated bilirubin levels are elevated; in neonatal infections, biliary tract pathology or metabolic diseases, conjugated bilirubin levels may be raised.

Tests to determine the cause of pathological jaundice
Once the diagnosis of pathological neonatal jaundice is established, other tests may be required to determine the cause of hyperbilirubinemia.

Liver function tests - to rule out primary liver disease

Urine culture and sensitivity – to rule urinary tract infection (UTI)

Neonatal infection screen (TORCH screen) – It is mandatory to do a TORCH screen (Toxoplasmosis, rubella, cytomegalovirus, herpes simplex) to rule out congenital infection as a possible cause for pathological jaundice.

Tests to rule out hemolysis – maternal and fetal ABO grouping and Rh typing, direct Coombs test on baby’s blood, reticulocyte count, hemoglobin and hematocrit levels, fetal red cell enzyme assays (G6PD and pyruvate kinase) to rule out inherited hemolytic disorders, blood film examination to study red cell morphology

Thyroid function tests – to test for congenital hypothyroidism

Imaging studies – ultrasound abdomen, hepatobiliary iminodiacetic acid (HIDA) radionuclide scan to look for liver and biliary pathology

Liver biopsy – rarely, a liver biopsy may be needed if other tests prove non-diagnostic

How is Neonatal jaundice treated?
Physiological jaundice presenting a few days after birth has to be monitored by measuring serum bilirubin regularly and if it is not severe and gradually resolves over the next few days it may not need any treatment at all.

Treatment of pathological neonatal jaundice depends on the following

• Severity of hyperbilirubinemia
• Rate at which bilirubin levels are rising
• Presentation within 24 hours of birth
• Whether baby is preterm or not (preterm babies are unable to tolerate high bilirubin levels well)
• Condition of the baby

The treatment modalities include the following

Phototherapy
Phototherapy should be urgently begun if bilirubin levels are rapidly rising in the baby. It involves placing the baby under the light source with as much of the skin exposed as possible (the eyes should be protected with pads).

The light waves are absorbed by the skin and convert the bilirubin into a harmless substance which is then excreted.

The temperature of the light source should be closely regulated, fluid intake of the baby should be increased to prevent dehydration and most importantly parent-infant interaction should be supported during this stage.

Exchange transfusion
In exchange transfusion, a part of the baby’s blood is removed and replaced with matching
blood transfusion. There are well established guidelines to perform exchange transfusion. The threshold bilirubin level for exchange transfusion in babies born at 38 weeks gestation or more is 100 micromol/L at birth and rises to 450 micromol/L at 42 hours of life. Values above the threshold level necessitates exchange transfusion. This is essential to prevent adverse effects of bilirubin toxicity on the brain.

Treatment of the underlying cause –
Antibiotics to treat UTI
Thyroid replacement in congenital hypothyroidism
Biliary atresia requires surgery within two months for a better outcome

Frequently asked questions
1. What do I do if my baby is jaundiced?
You should immediately consult the pediatrician (child specialist) to further investigate the cause and determine the severity of jaundice and decide upon further management.

2. What is breast milk jaundice?
Breast milk jaundice occurs in breast fed babies. This happens when the baby is unable to suckle properly and fails to gain weight as a result. Due to the low weight, the amount of bilirubin formed becomes relatively high with respect to the body weight and jaundice occurs as a result.

3. How is breast milk jaundice treated?
The treatment of breast milk jaundice is to ensure the baby gets enough milk and starts to gain weight. The mother should be counseled on the correct position and method of breastfeeding and feed as often as the baby demands.

4. Why is the rate of red cell breakdown higher in babies?
In babies, the red cells containing fetal hemoglobin (the hemoglobin occurring in fetal red cells) are replaced by new red cells containing adult hemoglobin. As a result the breakdown of red cells in the newborn is higher.

5. What is kernicterus
Kernicterus is a condition when excess amounts of bilirubin present in the blood get deposited in the brain and cause damage to the brain. The effects vary depending on the amount of bilirubin from being asymptomatic to severe brain damage and even death.

6. Why is phototherapy not done in case of conjugated hyperbilirubinemia?
Phototherapy is not needed in case of conjugated hyperbilirubinemia because conjugated bilirubin does not damage the brain or cause kernicterus.

7. What is the longterm prognosis for neonatal jaundice?
In most cases the longterm outcome in neonatal jaundice is very good with prompt diagnosis and treatment.


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 Post subject: Re: Neonatal Jaundice
PostPosted: 25 Dec 2017 18:00 
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Joined: 26 Feb 2013 10:59
Posts: 618
Lakshmi, This is an excellent presentation of Neonatal Jaundice. You mention that 60% of term babies and 80% of preterm babies develop jaundice. Does that mean all these babies will be checked by Trans cutaneous screening or a blood test? The topic is well covered and should help any med student to understand the subject.


Last edited by Badri on 30 Jan 2018 14:33, edited 2 times in total.

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 Post subject: Re: Neonatal Jaundice
PostPosted: 25 Dec 2017 19:55 
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Joined: 19 Dec 2017 14:21
Posts: 37
Badri wrote:
Lakshmi, This is an excellent presentation of Neonatal Jaundice. You mention that 60% of term babies and 80% of preterm babies develop jaundice. Does that mean all these babies will be checked by Trans cutaneous screening or a blood test? The topic is well covered and should help any med student to understand the subject.


Dr Badrinath, thank you for your kind words. As per my references only babies who are visibly jaundiced are tested for bilirubin. Routine testing is otherwise not recommended.


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 Post subject: Re: Neonatal Jaundice
PostPosted: 30 Jan 2018 15:08 
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Joined: 26 Feb 2013 10:59
Posts: 618
I have gone through some of the literature relating to measurement of bilirubin levels in neonates. Guidelines prescribed by American academy of pediatrics indicate that all neonates should be evaluated for hyperbilirubinemia before discharge from hospital and serum bilirubin should be checked in neonates at risk. Transcutaneous measurement of bilirubin concentration is an objective, noninvasive method, which provides real-time results and avoids pain due to blood sampling. Most of the hospitals now do a routine check using TCB before discharge. If TCB level is greater than 250 micromol/litre, you must check serum bilirubin levels.

A Transcutaneous Bilirubinometer in USA costs around $1000 and in India costs around Rs 100000.


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