Neonatal Physiologic Jaundice: This condition is common in newborns and can cause mild elevations in liver enzymes due to the breakdown of red blood cells and the liver's immaturity. It typically resolves on its own.

Viral Hepatitis: Although less common in infants, viral hepatitis can cause elevated liver enzymes. The mode of transmission could be vertical (from mother to child during birth) for hepatitis B and C.
Biliary Atresia: An important consideration, as early diagnosis and surgical intervention (Kasai procedure) can significantly improve outcomes. However, it typically presents with more pronounced jaundice and may not initially show with only mildly elevated enzymes.
Idiopathic Neonatal Hepatitis: A diagnosis of exclusion, where the liver inflammation is not due to identifiable causes like infections, metabolic disorders, or biliary atresia.

Galactosemia: A genetic disorder that affects the body's ability to metabolize galactose, a sugar found in milk. It can lead to severe liver disease if not promptly diagnosed and treated with a galactose-free diet.
Tyrosinemia Type I: A rare genetic disorder that can cause liver and kidney disease. Early detection through newborn screening and treatment can prevent severe complications.
Herpes Simplex Virus (HSV) Infection: Although rare, neonatal HSV infection can cause severe hepatitis and is critical to diagnose early due to its high mortality rate if left untreated.

Alagille Syndrome: A genetic disorder that affects the liver, heart, and other parts of the body. It can cause elevated liver enzymes due to a reduction in the number of bile ducts within the liver.
Cystic Fibrosis: While primarily known for its respiratory symptoms, cystic fibrosis can also affect the liver, leading to focal biliary cirrhosis and multilobular cirrhosis in some cases.
Alpha-1 Antitrypsin Deficiency: A genetic disorder that may cause liver disease and lung disease in affected individuals. The liver disease can range from mild to severe and may present in infancy.