High prevalence of autoimmune hepatitis among patients with primary sclerosing cholangitis

Background/Aims: Traditionally, autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC) are regarded as separate disease entities. We report on a group of patients that suggests the existence of an overlap syndrome of the two conditions and on the prevalence of this syndrome among patients with PSC. Furthermore, the impact of the recently revised AIH scoring system for diagnosing AIH in this context was assessed. Methods: Retrospective analysis of consecutive patients of a tertiary referral centre for liver disease with a diagnosis of PSC. Results: Diagnosis of the overlap syndrome was established for nine patients (8%) of a total group of 113 PSC patients. Four patients initially presented with features of AIH and in five cases PSC was diagnosed first. All patients responded to immunosuppressive therapy; in three cases long-term remission was achieved. Three patients underwent liver transplantation after 4 months and 7 and 9 years, respectively. The original and revised versions of the AIH scoring system gave essentially the same results in the patients with the PSC-AIH overlap syndrome. Conclusions: Patients with overlapping features of AIH and PSC may be more common than is currently assumed. Recognition of this syndrome is of clinical significance, considering the important therapeutical consequences.