Advantage of antithymocyte globulin induction in sensitized kidney recipients: a randomized prospective study comparing induction with and without antithymocyte globulin

Background. Sensitized kidney allograft recipients require special management to improve their outcome. One strategy is heavy immunosuppression with antilymphocyte antibodies. Controversy continues about the actual advantage of induction protocols whilst infections and cancers are a constant risk. In addition, little is known about how to handle sensitized patients with low levels of sensitization. Methods. In this study, we randomized sensitized renal transplant recipients, who received prophylactic treatment with or without antithymocyte globulin (ATG), in addition to a standard triple regimen consisting of cyclosporin, steroids and azathioprine at ATG discontinuation. The induction treatment consisted of a low-dose ATG course over 10 days. Randomization was stratified on the maximum PRA, according to the live following classes: 5% < PRA less than or equal to 20%, 20% < PRA less than or equal to 40%, 40% < PRA less than or equal to 60%, 60% < PRA less than or equal to 80% and 80% < PRA less than or equal to 100%. Results. Eighty nine patients were enrolled: 47 patients received ATG and 42 did not. ATG induction lowered the incidence of biopsy-proven acute rejection episodes from 64 to 38%, increased 1 year graft survival from 76 to 89% and was associated with a higher 1 year inulin clearance (37 +/- 15 vs 49 +/- 18 ml/min). ATG-associated side effects were restricted to leucopenia and thrombocytopenia, whereas bacterial and viral infections, gammopathies and cancers did not occur more frequently. ATG induction benefited all sensitized patients, and not only the hypersensitized patients. Conclusions. We conclude that ATG induction is beneficial for all sensitized patients, regardless of their level of sensitization, with regard to acute rejection episodes, graft survival and graft function. Low-dose ATG is sufficient and prevents additional complications.