Objective:To understand the causes of cholestatic infantile hepatitis syndrome (IHS)in Chongqing area. Methods:Serum HCMV-IgM

Tox-IgM

RuV-IgM

HSV-IgM and hepatitis virus markers(A

B

C and E)were detected by ELISA. Liver biopsy tissues were observed under light microscope and electromicroscope. Immediate early antigen(IEA)and early antigen(EA)of HCMV

HbcAg

BSEP and MDR3 were detected in liver tissues by immunohistochemistry stain assay. Results:The diagnoses in 36 patients with cholestatic IHS included HCMV hepatitis in 10 patients

HCMV and RuV co-infection in 1 patient

HCMV

HSV and RuV co-infection in 1 patient

Biliary atresia in 7 patients(5 complicated with HCMV infection and 1complicated with HCMV and HBV co-infection)

Glycogen storage disease in 2 patients

Niemann-Pick disease and HCMV hepatitis in 1 patient

and Lipid storage diseases with unknown type in 1 patient. Probable diagnoses included liver mitochondriopathy and HCMV hepatitis in 1 patient

siderosis and HCMV hepatitis in 1 patient

dyslipidoses in 1 patient

bile acid synthetic defect in 1 patient and progressive familial intrahepatic cholestasis Ⅰin 1 patient. There were also 7 patients the causes did not found. Conclusion:HCMV hepatitis is the main cause of infantile hepatitis syndrome in Chongqing

but it may be co-infected with other virus and complicated with inheritant metabolism liver diseases. The pathologic changes of liver tissues are helpful in diagnoses of biliary atresia and inheritant metabolism liver diseases in cholestatic IHS. BSEP and MDR3 defect were not found in cholestatic IHS in Chongqing area.