P0311 SEROLOGICAL AND HISTOPATHOLOGICAL FEATURES OF CHILDREN WITH AUTOIMMUNE HEPATITIS - OVERLAP SYNDROME

Abstract

Introduction: Autoimmune hepatitis in children is chronic progressive disease, which can coexist with hepatotropic viral infection and primary sclerosing cholangitis. The specifity of circulating autoantibodies can be used to distinguish between type I (ANA< SMA) and type II (LKM). Aim of the study was to compare the antibody profile and histopathogical changes in autoimmune hepatitis, coexisting other diseases. Methods: 100 children with autoimmune hepatitis type I and 21 children with autoimmune hepatitis type II have been scored (IAHP Report 1999) according to the histologic criteria (interface hepatitis, bridging necrosis, biliary lesions, granuloma formations, Pearl’s stain for iron), serum biochemistry (ALT level, alkaline phosphatase), gamma globulin concentration including IgG, serum autoantibodies (ANA, AMA, LKM, AMA, pANCA), viral markers (antibodies against HCV, antiHbs, Hbe, Hbc, PCR for HCV). Results: At the time of diagnosis histology of the liver was characterised by necroinflammatory changes accompanied by fibrosis and/or cirrhosis. Viral infection occurred in 8 children (2 children were infected by HCV, 6 children by HBV), 6 children demonstrated features of primary sclerosing cholangitis, including 3 children with ulcerous colitis. Necroinflammatory changes in autoimmune and viral hepatitis were severe (according to Batts&Ludwig 1995); in HBV: predominantly lobular changes, lymph follicle formations; in HCV: steatosis and Fe accumulation in the hepatocytes and Kupffer cells. Histological features of biliary changes and mild cholestasis were seen in all cases of primary sclerosing cholangitis; granuloma formation in the portal tracts in 2 cases. All children were treated with Azathioprine and Prednisolone (without Interferone in 8 cases of viral hepatitis). IN PSC: mitovhondrial pattern in ANA HEP-2 = coarse granular in the cytoplasm; cytokeratin pattern = dots in the nucleus and fibrous cytokeratin structure of the cytoplasm. IN AIH type II 10 children were anti-HCV positive, but only 3 of them were RNA positive. Conclusion: Variable autoantibody level with false positivity for anti HCV occurs in autoimmune hepatitis (7 children with PCR negative for HCV) and overlapping syndrome (2 0children with PCR positive for HCV). Histopathological changes in overlap syndrome are not diagnostic, but suggestive for the aetiology. Overlap syndrome in children responded poorly to classical treatment of autoimmune hepatitis.