Differential Diagnosis for a 2-Month-Old Infant with Bilirubin of 106 and Conjugated Bilirubin of 9

• Single Most Likely Diagnosis
  • Physiological jaundice: This condition is common in newborns and can persist up to 2-3 months of age. The levels of bilirubin provided, with a predominance of unconjugated bilirubin (total bilirubin 106, conjugated bilirubin 9), are consistent with this diagnosis. However, the high level of total bilirubin warrants further investigation to rule out other causes.
• Other Likely Diagnoses
  • Breast milk jaundice: This condition occurs in breastfed infants due to substances in the breast milk that can increase the reabsorption of bilirubin from the intestines. It typically presents in the first or second week of life but can persist.
  • Hemolytic disease of the newborn (if not previously diagnosed): Although less common, if the infant has a hemolytic condition (like Rh or ABO incompatibility) not diagnosed at birth, it could lead to elevated bilirubin levels.
• Do Not Miss Diagnoses
  • Biliary atresia: A serious condition where the bile ducts are blocked or don't develop normally, leading to conjugated hyperbilirubinemia. Early diagnosis is crucial for effective treatment, which often involves surgical intervention (Kasai procedure).
  • Neonatal hepatitis: Inflammation of the liver in a newborn, which can be due to various causes including infections, metabolic disorders, or genetic conditions. It's essential to diagnose and treat the underlying cause to prevent long-term liver damage.
  • Choledochal cyst: A congenital anomaly of the bile duct that can cause obstructive jaundice. Early detection and surgical intervention are necessary to prevent complications.
• Rare Diagnoses
  • Progressive familial intrahepatic cholestasis (PFIC): A group of rare genetic disorders that lead to cholestasis (reduction or stoppage of bile flow). These conditions can present with elevated conjugated bilirubin and require specific management.
  • Alagille syndrome: A genetic disorder that affects the liver, heart, and other parts of the body. It can cause jaundice due to a reduction in the number of bile ducts within the liver.
  • Metabolic disorders (e.g., galactosemia, tyrosinemia): Certain metabolic disorders can lead to liver dysfunction and elevated bilirubin levels. Early diagnosis through newborn screening or clinical presentation is critical for initiating appropriate treatment.