Neonatal Jaundice: Definition, Causes and Epidemiology

Definition and Epidemiology

• Neonatal jaundice is a yellowish discoloration of the skin and eyes in newborns due to elevated levels of bilirubin in the blood.
• Affects approximately 60% of term infants and 80% of preterm infants.
• Most common condition requiring medical attention in newborns.

Causes

• Physiological jaundice: Normal breakdown of fetal red blood cells, leading to increased bilirubin production.
• Pathological jaundice: Abnormal breakdown of red blood cells, e.g., due to blood group incompatibility, hemolytic disease, or infections.

Risk Factors

• Preterm birth: Increased risk of neonatal jaundice due to immature liver function.
• Family history: Increased risk if there is a family history of jaundice or hemolytic disease.
• Blood group incompatibility: Increased risk if mother's blood type is O and baby's blood type is A or B.

Signs and Symptoms

• Yellowish discoloration: Of the skin, eyes, and mucous membranes.
• Dark urine: Bilirubin accumulation in the urine.
• Fussy or lethargic behavior: In severe cases, bilirubin toxicity can cause neurological symptoms.

Diagnosis

• Physical examination: Visual inspection of the skin and eyes.
• Bilirubin levels: Measured through blood tests or transcutaneous bilirubinometry (TcB).
• Differential diagnosis: Rule out other conditions that may cause similar symptoms, such as sepsis or hypothyroidism.

Treatment

• Phototherapy: Exposure to specific wavelengths of light to break down bilirubin in the skin.
• Exchange transfusion: Replacement of the baby's blood with donor blood to reduce bilirubin levels.
• Pharmacological therapy: In rare cases, medications like phenobarbital may be used to enhance bilirubin excretion.

Complications

• Kernicterus: Bilirubin toxicity causing neurological damage and long-term sequelae.
• Hear loss: Bilirubin toxicity affecting the auditory nerve.
• Cerebral palsy: Rarely, severe bilirubin toxicity can contribute to the development of cerebral palsy.

Definition and Epidemiology

• Neonatal jaundice is a yellowish discoloration of the skin and eyes in newborns due to elevated levels of bilirubin in the blood.
• Affects approximately 60% of term infants and 80% of preterm infants.
• Most common condition requiring medical attention in newborns.

Causes

• Physiological jaundice occurs due to normal breakdown of fetal red blood cells, leading to increased bilirubin production.
• Pathological jaundice occurs due to abnormal breakdown of red blood cells, e.g., due to blood group incompatibility, hemolytic disease, or infections.

Risk Factors

• Preterm birth increases the risk of neonatal jaundice due to immature liver function.
• Family history of jaundice or hemolytic disease increases the risk.
• Blood group incompatibility (e.g., mother's blood type is O and baby's blood type is A or B) increases the risk.

Signs and Symptoms

• Yellowish discoloration of the skin, eyes, and mucous membranes.
• Dark urine due to bilirubin accumulation.
• Fussy or lethargic behavior in severe cases due to bilirubin toxicity causing neurological symptoms.

Diagnosis

• Physical examination involves visual inspection of the skin and eyes.
• Bilirubin levels are measured through blood tests or transcutaneous bilirubinometry (TcB).
• Differential diagnosis is necessary to rule out other conditions that may cause similar symptoms, such as sepsis or hypothyroidism.

Treatment

• Phototherapy involves exposure to specific wavelengths of light to break down bilirubin in the skin.
• Exchange transfusion involves replacement of the baby's blood with donor blood to reduce bilirubin levels.
• Pharmacological therapy (e.g., phenobarbital) may be used in rare cases to enhance bilirubin excretion.

Complications

• Kernicterus occurs due to bilirubin toxicity causing neurological damage and long-term sequelae.
• Hearing loss can occur due to bilirubin toxicity affecting the auditory nerve.
• Cerebral palsy can rarely occur due to severe bilirubin toxicity contributing to its development.