INCIDENCE AND RECURRENCE OF AUTOIMMUNE HEPATITIS IN LIVER TRANSPLANT RECIPIENTS

Abstract

144 AIM: The purpose of this study was to determine the frequency of autoimmune hepatitis (AIH) among liver transplant recipients and its incidence of recurrence after transplantation. We also extended our investigation to define the impact of AIH recurrence on patient and graft survival, episodes of rejection, liver function tests and other biochemical and histological parameters. MATERIALS AND METHODS: Between December 1984 and December 1998, 1429 individuals underwent orthotopic liver transplantation (OLTx) at our Institution. There were 753m and 676f. Mean age at transplantation was 48ys (sd 12). AIH was diagnosed according to the International Autoimmune Hepatitis Group guidelines. Recurrence was defined by the presence of plasmacytic infiltrates on liver biopsy in the absence of viral infection. All patients were treated with either cyclosporine (CyA) or tacrolimus (FK) based immunosuppression. Biochemical parameters (AST, ALT, ALK-P, GGT, T Bili, CR, WBC, HCT, PT, PTT) and liver biopsy specimens were evaluated before and after OLTx. RESULTS. AIH: 55 patients with a diagnosis of AIH underwent OLTx. There were 10m and 45f, with a mean age of 44.5ys (sd 13). When compared with all OLTx recipients, AIH recipients age was significantly lower, female sex was significantly more frequent, likelihood of rejection in the first 3,6, and 12 months was higher, and so was ACR requiring OKT3 in the first 12 months. There was no difference in recipient race, patient survival, and graft survival. When comparing lab values, ALT and HCT were significantly lower among AIH recipients at 1 and 2 ys post OLTx. There was no difference in AST, ALK-P, GGT, CR. PT, PTT, T Bili, WBC. AIH recurrence: There were 11 biopsy proven recurrences (1m, 10 f) of AIH after OLTx. Mean age at recurrence was 45.5ys (sd 13). 5 recurred within the first year after transplantation. None required retransplantation because of recurrent disease. When compared with non-recurrents, there was no statistically significant difference with respect to initial immunosuppression (FK or CyA), recipient and donor sex, age, and race, or patient and graft survival. No difference was observed in the incidence of ACR prior to recurrence, total number of ACR, or ACR treatment among recurrent and non-recurrent AIH recipients. When lab values at 1 and 2 years after OLTx were taken into account, there was a statistically significant increase in AST, ALT, and ALK-P among those who recurred. No difference was observed when considering GGT, T Bili, CR, PT, PTT, HCT, and WBC. DISCUSSION: AIH has an incidence of 4% among liver transplant recipients and a recurrence rate of 20% in liver allografts. Patients with AIH are more likely to be young women, and to have a higher incidence of ACR during the first post-transplant year. Recurrence should be suspected in recipients with abnormal liver function tests in the absence of infiltrates typical of ACR on liver biopsy, especially during the first year after transplantation.