Initial experience with tacrolimus rescue therapy in OKT3 resistant rejection.

Follow-up of 9 renal transplant recipients who were converted from cyclosporin A to tacrolimus (FK506) as recue therapy for intractable rejection is described. All patients initially received a cyclosporin A based immunosuppression. They developed biopsy proven acute rejections 22 +/- 11 days after transplantation which did not resolve by i.v. steroids and subsequent OKT3. Fifty-three +/- 11 days post transplantation the patients were converted from cyclosporin A to tacrolimus. After conversion to tacrolimus 6 patients developed a stabile transplant function. One transplant recipient who initially responded to tacrolimus lost his graft due to a chronic rejection 9 months following conversion. Two patients with never functioning kidneys remained on dialysis despite tacrolimus therapy. After conversion no serious adverse events occurred and only a slightly increased infection rate and hyperglycemia were noted as major side effects of tacrolimus. Tacrolimus rescue therapy was effective in treating acute renal allograft rejection unresponsive to steroids and OKT3. Tacrolimus rescue therapy was not accompanied by a substantial rise in complications. Patients with never functioning kidneys did not seem to benefit from tacrolimus rescue therapy.