[Desensitization protocols in immunized living donor kidney transplant recipients].

It is well known that the presence of alloantibodies against human HLA class I (A, B, C) and class II (DR, DQ) antigens in transplant recipients waiting for a first or subsequent kidney transplant has a significant negative impact on graft outcome, with increased acute and chronic rejection rates. HLA antibodies, present in hyperimmunized patients (PRA > 80%) as a result of pregnancies, blood transfusions and previous failed grafts, once thought to be a formidable barrier to renal transplantation, can now be overcome with excellent results by means of desensitization protocols in kidney transplant recipients from living or cadaver donors. Such pretransplant desensitization protocols consist of high-dose intravenous immunoglobulin infusions (IVIg-HD), plasmapheresis associated with low-dose IVIg (IVIg-LD) and immunoabsorption by protein-A sepharose or Ig-sepharose columns. All of the above treatments, associated in many cases with the anti-CD20 monoclonal antibody Rituximab, have been widely applied in living donor kidney transplant recipients showing donor-specific anti-HLA antibodies. Similar desensitization protocols have been used for non-A2 AB0-incompatible living donor kidney transplants. These techniques have allowed successful transplantation in this high-risk patient category by providing live donor kidneys that function promptly with minimal risk of early loss, and have consequently increased the organ donor pool. Long-term follow- up of these patients and the application on a wider scale of these techniques, which for many patients may represent the only realistic chance of a successful transplant, will provide the definitive answers about their real efficacy.