Idiopathic Neonatal Hepatitis
Grace E. Kim, MD
Key Facts
Terminology
Convenient term for clinical condition manifested by prolonged jaundice in neonates with variable but definable histologic picture
Microscopic Pathology
Predominately lobular histological changes
Syncytial giant cell hepatocytes with extramedullary hematopoiesis
Canalicular cholestasis and scattered to absent necrotic hepatocytes
Top Differential Diagnoses
Biliary atresia is very important to exclude because early surgical intervention is required
If neonatal hepatitis-like pattern of injury, use clinical information and molecular tests to exclude known disorders
INH is diagnosis of exclusion
 The characteristic features of INH include lobular giant cell transformation and extramedullary hematopoiesis. Ductular reaction is absent, and hepatocyte necrosis may not be apparent. |
 INH is primarily a lobular process with hepatocytes showing giant cell change and necrosis  along with cholestasis  . |
TERMINOLOGY
Abbreviations
Idiopathic neonatal hepatitis (INH)
Definitions
General term for clinical condition manifested by prolonged jaundice in neonates with variable but definable histologic picture
Clinicopathologic picture is termed neonatal hepatitis syndrome
Uniform clinical presentation but broad spectrum of causative disease processes
INH is a diagnosis of exclusion
ETIOLOGY/PATHOGENESIS
Unknown
Many different insults linked to this pattern of injury; if known etiologies are excluded, then idiopathic
