This is a multi-center project to establish a prospective database of clinical information and a repository of blood and tissue samples from children with diagnoses of neonatal liver diseases, such as biliary atresia and neonatal hepatitis in order to perform research in these liver problems. Children were screened and enrolled at presentation at the participating pediatric liver sites. Participants diagnosed with biliary atresia were followed intensively for the first year, at 18 months of age, then annually up to 20 years of age, liver transplantation, or resolution of the underlying liver disease. Other subjects diagnosed with cholestasis were followed on the same schedule; if there was complete (clinical and biochemical) resolution of their underlying liver disease off all therapy, there was one follow up visit within one year (preferably scheduled at the time of the next planned follow up visit or at 12 months of age, whichever was later) for data collection and to obtain blood samples. The development of a serum and tissue bank of specimens from children with various neonatal cholestatic disorders are for use by future investigations into the etiology and pathogenesis of hepatobiliary injury in the infant.

The data package available for request includes analysis datasets from multiple publications including combined data from the BASIC, LOGIC, and START studies.

Establish a database of clinical information and collect samples of blood, DNA, urine, and liver tissue for research purposes.

Inclusion Criteria:

• Infant's age less than or equal to 180 days at initial presentation at the ChiLDReN clinical site.
• Diagnosis of cholestasis defined by serum direct or conjugated bilirubin greater than 20% of total and greater than or equal to 2 mg/dL.
• The subject's parent(s)/guardian(s) willing to provide informed written consent.

• Acute liver failure.
• Previous hepatobiliary surgery with dissection or excision of biliary tissue.
• Diagnoses of bacterial or fungal sepsis (except where associated with metabolic liver disease)
• Diagnoses of hypoxia, shock or ischemic hepatopathy within the past two weeks (If the cholestasis persists beyond two weeks of the initiating event, the infant can be enrolled).
• Diagnosis of any malignancy.
• Presence of any primary hemolytic disease (except when diagnosed with biliary atresia or another cholestatic disease being studied by ChiLDREN).
• Diagnosis of any drug or Total parenteral nutrition (TPN)-associated cholestasis (except when diagnosed with biliary atresia or another cholestatic disease being studied by ChiLDREN).
• Diagnosis with Extracorporeal membrane oxygenation (ECMO)-associated cholestasis.
• Birth weight less than 1500g (except when diagnosed with biliary atresia).

This study is ongoing.