Autoimmunity after liver transplantation: a frequent event but a rare clinical problem.

Autoantibodies are frequently detected after liver transplantation (LT), but their role is unclear. This study was designed to address three points: autoantibody prevalence pre-LT and over time up to five yr after LT, identification of possible predictors of autoantibody formation, and correlation between autoantibodies and graft dysfunction. To these aims, we retrospectively evaluated 92 consecutive LT recipients for whom prospectively stored frozen sera were available for autoantibodies assessment by immunofluorescence. The overall autoantibody prevalence resulted significantly higher after LT than before LT (64% vs. 27%, p < 0.001 and 35.9% vs. 8.7%, p < 0.001 considering cutoff titer of ≥ 1:80 and ≥ 1:160, respectively). Recipient gender, donor age and gender, and indication for LT and main immunosuppressant (cyclosporine vs. tacrolimus) were not associated with the presence of autoantibodies. Patients with graft dysfunction had a significantly higher autoantibody prevalence irrespective of the etiology of liver injury as compared to those patients with persistently normal liver biochemistry, but only for cutoff titers ≥ 1:160 (p = 0.004). No cases of de novo autoimmune hepatitis were observed. In conclusion, autoantibodies are very frequently detected after LT also at high titers and their association with graft dysfunction likely represents an aspecific indicator of liver injury.