Autoimmune hepatitis in Sweden

Abstract: Autoimmune hepatitis (AIH) was identified as an entity by the Swedish professor Jan Waldenström in the 1950s. It was then denoted lupoid hepatitis, characterized by liver inflammation and most often affecting young women. During the years the diagnosis has become more defined (as the non A non B hepatitis has been identified as Hepatitis C) and now can be safely separated from other diseases with liver inflammation. Studies of epidemiological data and long term prognosis have been scarce in the literature. Within a collaboration between the university hospitals in Sweden, we collected what we believe is the largest cohort in the world of patients with AIH. Data from the medical records of 473 individuals was, after AIH-score calculations where the diagnosis was confirmed, collected in a data base, in which most of the analysis was done. Data from the Swedish national registers of cancer, death cause, and birth register was searched for these patients as well as controls. The aim of the thesis was to explore epidemiological and clinical outcome of AIH.The onset of AIH may be at any age, but the incidence seems to increase after 50 years of age; 75% are females, the overall incidence (0.85/ 100,000 inhabitants and year) and prevalence (11/100,000 inhabitants) are figures that are within the range of another but smaller Scandinavian study. Approximately 30 % had cirrhosis already at diagnosis and 87% displayed at some time positive auto-antibodies indicating AIH (Smooth muscle ab and or antinuclear ab).  Indications of future risk for liver transplantation or death is an advanced AIH at diagnosis with liver cirrhosis, decompensated liver disease, elevated PK INR as well as age. Acute hepatitis-like onset seems to carry a lower risk for later liver transplantation or death. Current Swedish national therapy traditions with immune suppression seem to be well tolerated. Five and ten years overall life expectancy does not differ from controls. Thirty-five women gave birth to 63 children, for 3 after liver transplantation of the mother. Thirteen of the women had liver cirrhosis. Current pharmacological treatment seems to be safe both for the patient and the foetus. Thirty percent of the patients experienced flair after delivery. It has been supposed that there is an overrisk for hepatocellular cancer (HCC) associated with AIH. Our figures are the first in the world to be presented that confirms a twenty-three fold overrisk (95% Confidence Interval 7.5-54.3) for hepatobiliar cancer. We found as well an overrisk of non-Hodgkin lymphomas of 13.09 (95% CI 4.2-30.6).Conclusion:  Our epidemiological results confirm that AIH is a fairly uncommon disease, and that many already at time of diagnosis have an advanced disease with liver cirrhosis. There is a clear overrisk for HCC and lymphoma. For those women with AIH who become pregnant the prognosis for the child as well as for the mother is good, even for those women who already have compensated cirrhosis. There is a risk for relapse after delivery. The overall survival for AIH patients with current therapy is good.