BACKGROUND: Liver biopsy plays an important role in accurate diagnosis of various liver diseases in children and liver damages caused by systemic illnesses. This study was designed to evaluate the value of liver biopsy in diagnosis of liver diseases in children and explore the relationship between their pathological changes and clinical manifestations.
METHODS: One-second liver biopsy was performed in 1023 pediatric patients with liver diseases at our department from 1983 to 2000.  Diagnosis of viral hepatitis was based on the diagnostic criteria formulated by the Chinese Society of Infectious and Parasitic Diseases in 1995.  Inflammatory changes of the liver were graded from 0 to 4 (G0-4). 
RESULTS: Liver biopsy was performed successfully in 1020 patients including 135 infants and young children, of whom 90% were hospitalized patients with chronic liver diseases. Hepatitis virus was the leading cause for chronic liver diseases, among which hepatitis B was detected in  75.4% of the patients. Sixty-nine patients showed liver impairment induced by disorders relevant to that metabolism, Wilson’s disease, and glycogen storage disease. Liver inflammatory injury  (<G2) was found in 76.4% of the patients with hepatitis B in contrast to 61.2% of adult patients. It was aggravated with age in the patients with hepatitis B and C and peaked at their schooling age. Moderate or severe liver injuries were not seen in infants with chronic hepatitis B. Two infants had chronic hepatitis C. Patients with non-viral hepatitis showed specific, non-specific histological changes and liver cirrhosis.
CONCLUSIONS: Liver inflammatory injuries are more common in children with hepatitis B than in adult patients, and severe inflammatory changes are seen in children with hepatitis B and C at their school age. Liver injuries induced by non-viral factors seem to be increasing, and liver biopsy in children is safe and feasible in the diagnosis of liver diseases.