Primary sclerotizing cholangitis (PSC) is a chronic cholestatic liver disease of unknown etiology. The presence of autoimmune phenomena in child patients with PSC can lead to confounding of the disease with autoimmune hepatitis (AIH). The objective of the investigation was to draw attention to the incidence of common autoimmune phenomena in childhood and detect differences of the two diseases. Methods: In the retrospective study groups of patients were included with PSC (12 children) and with AIH (11 children). In both groups the clinical, biochemical and immunological results were compared. For comparison the diagnostic scoring system for AIH was used. Results: In the group of patients with PSC boys predominated (3:1) contrary to patients with AIH (1:5). In 70% patients with PSC colonoscopic and histological examination confirmed the presence of an idiopathic inflammation of the gut. At the statistical level p = 0.05 significant differences were found in the levels of IgG, GMT and C4 complement. In patients with PSC predominated antibodies against neutrophil cytoplasm (83.3%), antinuclear antibodies were the most frequent finding in children with AIH (72.7%). On histological examination changes of the bile ducts were described in 75% patients with PSC and only in one patient with AIH. Periportal hepatitis was found in 80% patients with AIH and 58% with PSC. The mean histological score of the applied diagnostic system was higher in patients with AIH. Antigen DR3 was found in 64% children with AIH and only in 25% with PSC. DR4 was found in two patients with PSC. All patients with AIH except one and all patients with PSC responded well to immunosuppressive treatment. Criteria for the diagnosis AIH were fully met by 100% patients with AIH and 58% with PSC. The diagnostic score of patients with AIH before and after treatment was significantly higher. Conclusion: In the investigated groups of patients with PSC and AIH the incidence of autoimmune phenomena is so frequent that it supports the hypothesis of an autoimmune etiology of PSC in child patients. For definite differentiation of these two diseases cholangiographic examination (ERCP) is necessary.

        Key words: primary sclerotizing cholangitis – autoimmune hepatitis – scoring system