Hashimoto's encephalopathy after intensive lymphocyte depletion with rabbit anti-thymocyte globulin in a renal transplant patient

There has been no reported case of Hashimoto's encephalopathy (HE) ('steroid-responsive encephalopathy associated with autoimmune thyroiditis', 'SREAT'), in the renal transplant recipient population. We describe the case of a 55-year-old female with Type-1 diabetes who presented 2 years posttransplantation in a comatose state that had developed over the preceding 24 h. The patient had received a short, intensive course of rATG induction at the time of transplantation and early steroid withdrawal. After 6 months she had been withdrawn from calcineurin inhibitors and was maintained on mycophenolate mofetil and sirolimus. Systematic workup determined the cause of her coma to be HE. High-dose steroid therapy resulted in complete resolution of the patient's symptoms. The literature regarding the diagnosis, course and treatment of HE is reviewed and the possibility that increased use of steroid-free immunosuppression and intensive lymphocyte depletion regimens may increase the prevalence of de novo autoimmune disease is discussed.