Neonatal jaundice

Causes of Neonatal Jaundice

In newborns, jaundice typically occurs because their liver is not fully mature and may not be able to process and excrete bilirubin efficiently. However, there are various causes and types of neonatal jaundice:

1. Physiological Jaundice:

• This is the most common and is considered a normal, temporary condition that affects many newborns, particularly those born preterm.
• It occurs because the newborn’s liver is immature and not yet efficient at processing bilirubin.
• It usually appears 2-4 days after birth and peaks around the third to fifth day, typically resolving by 2 weeks of age in full-term babies and by 3-4 weeks in preterm babies.

2. Breastfeeding Jaundice:

• Early breastfeeding jaundice can occur in the first few days of life when breastfeeding is not well-established, leading to insufficient milk intake. This can cause dehydration, which may increase bilirubin levels.
• Breast milk jaundice can develop later, usually after the first week, due to substances in the breast milk that interfere with the liver’s ability to process bilirubin.
• Breastfeeding jaundice can last for several weeks but is generally not dangerous if managed properly.

3. Pathological Jaundice:

• This is a more serious form of jaundice that develops in the first 24 hours of life or persists beyond the normal duration of physiological jaundice. It usually signals an underlying problem and requires prompt medical attention.
• Possible causes include:
  • Hemolysis (destruction of red blood cells) due to conditions like Rh incompatibility or ABO incompatibility, where the mother’s antibodies attack the baby’s red blood cells.
  • Infections (such as sepsis or urinary tract infections).
  • Genetic disorders, such as G6PD deficiency (a condition that leads to red blood cell breakdown under certain conditions).
  • Liver diseases (e.g., hepatitis, biliary atresia).
  • Enzyme deficiencies (e.g., conjugated hyperbilirubinemia).

4. Hemolytic Disease of the Newborn (HDN):

• Hemolytic disease occurs when the baby’s blood type is incompatible with the mother’s. This can cause the baby’s immune system to destroy its own red blood cells, leading to an increase in bilirubin.
• Rh incompatibility: If the mother is Rh-negative and the baby is Rh-positive, the mother’s immune system may produce antibodies that attack the baby’s red blood cells.
• ABO incompatibility: This occurs when the mother’s blood type is O, and the baby’s blood type is A, B, or AB. The mother may produce antibodies that attack the baby’s red blood cells.

5. Biliary Atresia:

• This is a serious, albeit rare, liver condition in which the bile ducts are blocked or absent, preventing bilirubin from being excreted from the liver into the intestines. It can cause progressive liver damage and requires prompt treatment.

6. Other Causes:

• Prematurity: Preterm infants are more likely to develop jaundice because their liver function is less mature.
• Low birth weight: Babies with low birth weight, particularly those who are underweight and premature, may have a higher risk of developing jaundice.
• Infections: Certain infections, such as sepsis, can impair the baby’s ability to process bilirubin.
• Dehydration or insufficient feeding: Babies who are not feeding properly or are dehydrated may experience higher bilirubin levels.

Symptoms of Neonatal Jaundice

The primary sign of neonatal jaundice is a yellowish tint to the skin and the whites of the eyes (sclera). Other signs include:

• Yellowish skin tone (usually starting from the face and moving downward to the chest, abdomen, and limbs).
• Yellow sclera (yellowing of the whites of the eyes).
• Lethargy or poor feeding (in severe cases, babies may seem drowsy or have difficulty latching during breastfeeding).
• Dark-colored urine (bilirubin in the urine may make it look darker).
• Pale or light-colored stools (bilirubin is excreted in the stool, and pale stools may indicate a liver issue).

In cases of severe jaundice, the baby may become excessively sleepy, difficult to wake, or exhibit signs of poor muscle tone. If untreated, very high levels of bilirubin can lead to kernicterus, a rare but serious condition that results in brain damage.

Diagnosis of Neonatal Jaundice

Jaundice in newborns is often first identified by a physical exam, but additional tests may be needed to determine the cause and severity. These include:

1. Serum Bilirubin Test: Blood tests measure the level of bilirubin in the baby’s blood. A high bilirubin level confirms jaundice and helps determine whether it’s within a safe range or requires treatment.
2. Direct Coombs Test: This test helps determine if the jaundice is caused by hemolytic disease of the newborn, indicating blood type incompatibility.
3. Blood Tests: Additional blood tests to check for infection, liver function, and possible enzyme deficiencies may be done.
4. Ultrasound or Liver Biopsy: If there is a suspicion of structural liver issues (such as biliary atresia), imaging or biopsy may be required to examine the liver.

Treatment of Neonatal Jaundice

The treatment for neonatal jaundice depends on the severity of the condition, its underlying cause, and the baby’s age. The main goal is to reduce the bilirubin levels to prevent potential complications.

1. Phototherapy (Light Therapy):

• The most common and effective treatment for physiological jaundice is phototherapy. This involves exposing the baby’s skin to special blue light, which helps break down the bilirubin in the skin.
• The light transforms bilirubin into a form that the baby’s liver can more easily excrete through urine and stool.
• Phototherapy is often performed in a hospital setting, but in some cases, home phototherapy may be an option for less severe jaundice.

2. Exchange Transfusion:

• In severe cases of jaundice, when bilirubin levels are very high and the baby is at risk of developing kernicterus (brain damage), an exchange transfusion may be necessary. This procedure involves slowly replacing the baby’s blood with fresh donor blood to remove excess bilirubin.
• This is a rare procedure and is usually only done if bilirubin levels do not respond to phototherapy.

3. Intravenous Immunoglobulin (IVIg):

• For jaundice caused by blood incompatibility (e.g., Rh or ABO incompatibility), IVIg may be administered to help reduce the level of antibodies that are attacking the baby’s red blood cells.

4. Adequate Feeding:

• Ensuring that the baby feeds well (either breast milk or formula) is critical. Feeding helps the baby pass bilirubin in the stool, reducing its level in the body. Babies who are not feeding properly may need supplemental feeding or hydration.

5. Treatment of Underlying Causes:

• If jaundice is caused by an underlying condition such as infection, liver disease, or hemolysis, treatment will focus on managing that specific condition (e.g., antibiotics for infections, or medications for enzyme deficiencies).

Preventing Neonatal Jaundice

While physiological jaundice cannot always be prevented, the risk of severe jaundice or complications can be reduced through the following measures:

• Early and frequent feeding: Ensuring that the baby is feeding well in the first few days of life helps prevent dehydration and encourages the excretion of bilirubin through stools.
• Monitoring: Newborns should be closely monitored for signs of jaundice, particularly in the first few days of life.
• Screening for Rh and ABO incompatibility: In high-risk pregnancies, blood tests can help identify potential blood group incompatibilities and allow for early intervention.
• Premature babies: Premature infants should be monitored closely for jaundice, as they are more likely to develop it due to immature liver function.

Prognosis

• Most babies with physiological jaundice recover fully without any long-term effects. Jaundice typically resolves on its own or with phototherapy, and the liver function returns to normal.
• In cases where jaundice is pathological or severe (due to infections, hemolytic disease, or liver disease), the prognosis depends on the underlying cause. If treated early, most babies recover with minimal or no long-term consequences.
• Kernicterus (brain damage caused by very high bilirubin levels) is rare but can lead to permanent neurological damage, including cerebral palsy, hearing loss, and developmental delays. Early treatment significantly