Introduction
Neonatal jaundice, also called neonatal hyperbilirubinemia, results from raised total serum bilirubin (TSB) and clinically presents as yellowish skin discoloration and sclera, and mucous membrane. Neonatal jaundice is sometimes called "physiological Jaundice," a mild, transient, and self-limiting condition. However, it is compulsory to differentiate this from a more severe form called "pathological Jaundice." Misdiagnosis of this condition may result in bilirubin encephalopathy and associated neurological sequelae.
What Is Neonatal Jaundice?
The word jaundice derives from the French word "jaune," which means yellow. Neonatal jaundice or neonatal hyperbilirubinemia results from raised total serum bilirubin (TSB) and clinically displays yellowish skin discoloration. It is the most typically experienced medical issue in the first two weeks of life. A common cause of hospitalization after birth. Preterm newborns develop clinical jaundice in the first week after birth.
In most cases, it is a mild, self-limiting condition that resolves without treatment, known as "physiological jaundice." Phototherapy and exchange transfusions are the mainstays of treatment of UHB, and a subset of patients also react to intravenous immunoglobulin (IVIG). Treatment of CHB is more complex and depends mainly on the causative factor. Despite advances in treating and managing hyperbilirubinemia, it remains an important cause of morbidity and mortality.
What Is Bilirubin?
Bilirubin is a yellowish-pigmented substance resulting from the normal breakdown of hemoglobin in red blood cells. Heme is separated from the hemoglobin during the breakdown of red blood cells. Heme is an essential substance in the red blood cells that binds with the oxygen in the lungs and carries it to other parts and tissues. The heme is converted to biliverdin (a green-pigmented substance). The biliverdin is further transformed into unconjugated bilirubin by biliverdin reductase. The unconjugated bilirubin is not water-soluble and cannot be removed from the body in this form. Instead, it is converted into a water-soluble form called conjugated bilirubin by an enzyme uridine diphosphate - glucuronyl transferase (UDP-GT). This bilirubin is taken up by the liver and is excreted out of the body in the urine and stools.
What Are the Causes of Neonatal Jaundice?
Unconjugated hyperbilirubinemia (UHB) is the reason for clinical jaundice in most neonates. Sometimes, some infants have conjugated hyperbilirubinemia (CHB), which is pathological and indicates an underlying medical or surgical cause.
Conjugated Hyperbilirubinemia (CHB) or Direct Hyperbilirubinemia
Conjugated hyperbilirubinemia occurs as a result of an underlying liver disease or condition like biliary obstruction (a block in the bile duct), alcoholic hepatitis (inflammation of the liver due to alcohol consumption), or an autoimmune disease (a disease that occurs when the body's immune system damages its healthy cells or organs). Conjugated bilirubin is a byproduct of heme metabolism. Therefore, when conjugated bilirubin levels are higher than usual, it is called conjugated hyperbilirubinemia.
Unconjugated Hyperbilirubinemia (UHB) or Indirect Hyperbilirubinemia
Unconjugated hyperbilirubinemia is the standard type and is either physiological or pathological. Physiological jaundice accounts for most cases of neonatal hyperbilirubinemia and results from a physiological alteration in neonatal bilirubin metabolism.
Various causes.
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Diabetic mother.
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Congenital hypothyroidism.
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Drugs like sulfa drugs, Ceftriaxone, and Penicillins.
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Intestinal obstruction.
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Pyloric stenosis.
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Breast milk jaundice and breastfeeding jaundice.
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Idiopathic neonatal hepatitis.
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Parenteral nutrition-induced cholestasis.
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Gestational alloimmune liver disease.
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Neonatal hemochromatosis.
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Cytomegalovirus infection.
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Alpha-1-antitrypsin deficiency
What Are the Symptoms of Neonatal Jaundice?
The symptoms are noticeable within a few days after birth. Symptoms generally depend on the underlying disease, but some common symptoms include:
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Brown-color urine.
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The skin, mucous membrane, and eye sclera appear yellow.
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Nausea and vomiting.
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Unintentional weight loss.
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Feeling weak and tired.
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Altered mental state.
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Anorexia (an eating disorder where people eat less not to gain weight).
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Dyspnea (shortness of breath).
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Diarrhea.
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Abdominal pain.
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Swelling in the legs.
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Chills.
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Changes in stool appearance.
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Hematemesis (blood vomiting).
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The child seems very sluggish and tired.
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Fever.
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Poor feeding habits.
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High-pitched cry and is always fussy.
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Respiratory distress.
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Low muscle tone with muscle spasms.
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Convulsions and seizures.
How to Diagnose Neonatal Jaundice?
During the newborn physical examination, the baby will be evaluated for jaundice within 72 hours of birth. The symptoms of jaundice after you return home can sometimes take up to a week to appear. The various diagnostic tools for diagnosing neonatal jaundice are mentioned below;
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Physical examination is done to check for yellowish discoloration of the skin and eyes, tenderness or pain in the right upper region above the abdomen, or the presence of a mass in the abdomen.
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Bilirubin Test: A bilirubinometer is a small device used in diagnosing neonatal jaundice in babies by calculating the bilirubin level. It indicates light when it is touched onto the skin.
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A blood test is performed to screen total and direct bilirubin levels. If the levels are elevated, it suggests cholestasis or hepatocellular injury.
Other diagnostic tests are performed depending on the liver disease, like
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Complete Blood Count: It is performed to check for anemia (reduced numbers of red blood cells) in hemolysis disease (destruction of red blood cells).
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Viral Hepatitis, Serologic Studies: A blood test to perform serologic studies to detect viral infection.
What Is the Treatment for Neonatal Jaundice?
The treatment of neonatal jaundice focuses on two primary goals. They are:
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To reduce the blood's bilirubin levels and prevent neurotoxicity.
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To prevent the recurrence of high bilirubin levels.
The treatment protocols followed for kernicterus are,
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Transfusion Therapy: This is indicated when there is bilirubin encephalopathy and when the serum bilirubin levels are more than 20 to 25 mg/dL. It is a more effective method for removing the bilirubin in the baby's blood.
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Phototherapy: It is the first line of treatment done for jaundice. Phototherapy uses light energy to convert the insoluble bilirubin molecules to water-soluble molecules, so they are easily excreted from the body. However, during phototherapy, special care should be taken for eye protection. The eyes are covered with a mask as the light can cause damage to the retina of the eye.
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Intravenous Immunoglobulin is used in cases of immunologically mediated conditions such as Rh-incompatibility or other blood group incompatibilities that cause neonatal jaundice. The intravenous immunoglobulin transfusion reduces the chances of blood transfusions in some cases.
Conclusion
Neonatal jaundice has become a common medical condition in newborns. Although it is common, it may result in severe conditions such as brain and other neurologic damage if untreated. Hence proper diagnosis and treatment are essential. As soon as kernicterus is suspected, treatment should be begun without further delay to avoid unnecessary complications. In addition, parents should be counseled on how to feed their babies and enhance breastfeeding practices. Regular follow-ups and medical examinations are mandatory within 48 to 72 hours after birth.
