20. JAUNDICES IN THE NEONATAL PERIOD AND INFANCY

Question 1

How common is jaundice in neonates?

Answer 1

It is observed in about 60% of
healthy neonates during the first week of life (so-called physiological jaundice) and in about 80% of preterm neonates.

Question 2

Physiological characteristics of bilirubin production and metabolism in neonatal period:

Answer 2

• Bilirubin is a product of haemoglobin metabolism.
• One gram of haemoglobin yields 35 mg of bilirubin. Neonates have 2-3 times higher
  bilirubin production than adults because of increased number and shorter life of
  erythrocytes (70-90 days
  compared to 120 days in adults.

Question 3

Aetiology:

Answer 3

Risk factors for hyperbilirubinemia are blood group incompatibility between mother and
foetus, prematurity and hyperbilirubinemia in a previous child, large cephalohematomas, haemorrhages,
delayed passage of meconium, breastieeding, poor tolerance to enteral feeding, dehydration,
polycythaemia, and neonatal infections.

Question 4

The causes of neonatal jaundice can be divided into three groups:
1. Increased bilirubin level:

Answer 4

hemolytic causes:
increased level of indirect bilirubin and reticulocytes, anemia

Commbs-positive:
-Rh factor
-ABO or other antigen incompatibility: hemolytic disease of the newborn

Coombs-negative:
- Sphyrocytosis
-Elliptocytosis
-congenital enzyme disorders (glucose 6 phosphat dehydrogenese, pyruvate kinase), medicines
Non-haemolytic causes:
- increased level of unconjugated bilirubin, normal reticulocyte count
- Cephalohematomas, bruising

• delayed and insufficient enteral nutrition, intestinal abnomralities.

Question 5

The causes of neonatal jaundice can be divided into three groups:
2. Reduced bilirubin conjugation:

Answer 5

• Characteristics: elevated level of unconjugated bilirubin, normal reticulocytes count
• Physiologic jaundice: Crigler-Najjar synrom type 1 and 2, Gilbert syndrome, lucey-Driscoll syndrome,
  Hypothyroidism, breast milk jaundice

Question 6

The causes of neonatal jaundice can be divided into three groups:
3. Impared bilirubin excretion:

Answer 6

• Charecteristics: increased level of total bilirubin
• Atresia of extrahepatic bile duct: bile duct cyst, primary sclerosing cholangitis, neoplasm, Dubin-
  johnson syndrome, Rotor syndrome, abnormalities of intreahepatic biliary tree, progressive familial

intrahepatic cholestasis
- Infections
- Neonatal hepatitis
- Metabolic diseases with liver involvement: alpha anti trypsin defeciency, galactosemia, fructose
intolerance, Niemann pick disease, tyrosinemia.

Question 7

Early jaundice:

Answer 7

Appearance of neonatal jaundice in first 24 hours of life is
always pathological, Early jaundice is most often unconjugated and is a result
from haemolytic disease of the newborn (blood incompatibility by Rhesus factor
or ABO antigens) and infection.

Question 8

Main clinical symptoms:

Answer 8

• extravasation, subcutaneous haemorrhages, purpura, petechiae, pallor, plethora, hepatosplenomegaly,
  symptoms of transplacental or bacterial infection.neurological symptoms – hypertonia, opisthotonos,
  convulsions, abnormal crying and abnormal eye movement, bowel
  obstruction, urine and faeces colour, symptoms of hypothyroidism.

Question 9

Physiological jaundice:

Answer 9

appears after 2 days with usually not very high levels of indirect bilirubin (<240
umol/L).

Question 10

• Jaundice is clinically visible at bilirubin levels

Answer 10

> 86- 172 umol/L.

Question 11

Prolonged jaundice:

Answer 11

(>14 days): Presentation of jaundice after 14 days is not physiological, but indirect
jaundice is often benign and observed in children on natural feeding. Prolonged conjugated/direct
hyperbilirubinemia is always pathological.

Question 12

Kernicterus:

Answer 12

• Early symptoms of kernicterus are non-specific usually occurring 3 to 4 days after birth: poor feeding,
  squeaky crying, and hypotony.
  -Later symptoms include overexcitability, seizures, apnoea, and opisthotonos. Chronic symptoms are
  presented by athetoid cerebral palsy, loss of hearing, oculomotor paralysis, dental dysplasia and
  retardation in development.

Caused by unconjugated bilirubin

Question 13

Treatment:

Answer 13

• Phototherapy with blue light (wavelength 450-490 nm) converts bilirubin stored in skin to a water-
  soluble bilirubin photoisomer, which is excreted in urine and bile.

-Exchange blood transfusion is the fastest way of reducing serum bilirubin level and is most commonly
used in haemolytic disease of the newborn due to maternal-foetal incompatibility by Rhesus factor.
Exchange transfusion eliminates both bilirubin and antibodies against the erythrocytes of the newborn.
The procedure is performed through umbilical vessels with donor blood (typically blood group 0, Rhesus
factor negative) as the newborn’s blood is exchanged 2 or 3 times . Incidence of
- RhD 1gG is administered to Rh negative mothers in cases of suspected fetal bleeding.
- Possible mechanism of action of RhD immunoglobulin is covering the surface of foetal erythrocytes
containing Rh antigens.
- It is currently recommended the administration of RhD igG 300 ug im. to any Rh-negative woman who
presents with antenatal bleeding, potential foetal-maternal bleeding or previous delivery of Rh-positive
child.

Question 14

Diagnosis of direct hyperbilirubinemia

Answer 14

• physical examination, liver enzyme tests, alkaline phosphatase, liver function tests, blood coagulation
  status, bilirubin level with fractions, alpha-fetoprotein, a1-antitrypsin, abdominal echography, sweat test,
  TORCH screening, screening for inborn errors of metabolism, percutaneous liver biopsy, isotopic
  excretion tests, and radioisotope scans.

Treatment depends on aetiology of direct hyperbilirubinemia. In extrahepatie biliary atresia, Kasal
hepatoportoenterostomy is performed. Success of this intervention depends on early diagnosis.
In many cases liver transplantation is required.