CLINICAL IMMUNOSUPPRESSION - KIDNEY EARLY

K. Gaurav¹, K. Brayman¹, T. Schmitt¹, C. Spencer¹, S. Sanoff¹, D. Keith¹, P. Lobo^2
1Nephrology, University of Virginia, Charlottesville/VA/UNITED STATES OF AMERICA, ²Nephrology, University of Virginia, Charlottesville/UNITED STATES OF AMERICA

Body: Introduction: There is a need to attempt kidney transplants in sensitized recipients with living donors and patients with ABO incompatible living donors especially since their waiting time on the deceased donor list is excessively prolonged (>4 yrs). One approach is to desensitize the patients pre-transplant, as has been attempted by few other centers. However there is no consensus on how low the anti-HLA antibodies need to be reduced prior to transplant so as to avoid post-transplant rejection, which very often is a precursor of chronic allograft nephropathy. Similarly there is no data regarding the level of maintenance immunosuppression required to prevent chronic graft loss. Methods: Since May 1^st 2006, we performed 20 kidney transplants in highly sensitized patients who were crossmatch positive against their donor and in 8 patients who were ABO incompatible with their donors. All these patients underwent a desensitization protocol treatment which included the use of Cellcept and Rituximab, at least 6 weeks pre-transplant as well as Plasmapheresis and IVIG given 2-3 wks pre-transplant to decrease antibody levels such that they were not detectable by the cytotoxic assay but were detectable by either the flow crossmatch or only by the single antigen Luminex beads. Post transplant, patients were maintained on higher doses of prednisone (10-15mg/day), CellCept (2-2.5g/day) and Prograf. Results: Out of the 20 highly sensitized patients who underwent the treatment protocol and subsequently the transplant, 18 patients still have a functioning graft at an average follow-up of 27.7 months with a mean serum creatnine of 1.3 mg/dL and no albuminuria. Seven of nine patients with a positive flowcrossmatch had humoral rejection episodes (in the first month post transplant) resulting in loss of one allograft. None of the 11 patients that had antibodies detectable only by Luminex had a rejection episode. The difference in rejection episodes between the flow crossmatch positive patients and flow crossmatch negative patients is statistically significant (p<0.0003). Two of these 20 patients died after one year of follow-up, one with severe heart failure and the other with sepsis secondary to cellulitis/diabetes. All 8 ABO incompatible patients have a functioning graft after a mean follow-up of 27 months and a mean serum creatnine of 1.1 mg/dL. Only one of these 8 patients had a rejection episode. Conclusion: Our data indicates that for a successful long-term outcome in highly sensitized and ABO incompatible patients, it would be beneficial to significantly reduce antibodies pre-transplant as well as maintain these patients on more immunosuppression.

Disclosure: All authors have declared no conflicts of interest.