The New OPTN Kidney Allocation Policy: Potential for Inequitable Access Among Hi

[Clark]

http://onlinelibrary.wiley.com/doi/10.1111/ajt.13061/full

The New OPTN Kidney Allocation Policy: Potential for Inequitable Access Among Highly Sensitized Patients
R. A. Bray1,*, P. Brannon1, C. Breitenbach2, C. Bryan3, D.-F. Chen4, J. Lai5, T. McRacken6, A. Kirk7, B. Kaplan8, T. Pearson9 andH. M. Gebel1
DOI: 10.1111/ajt.13061
American Journal of Transplantation
Early View (Online Version of Record published before inclusion in an issue)

To the Editor:

In 2013, the Organ Procurement and Transplantation Network approved a new national kidney allocation scheme (KAS) for deceased donor (DD) transplantation. Among the many attributes of the new policy was the decision to proactively address organ allocation to highly sensitized patients, long recognized to be the most disadvantaged group on the waiting list. Beginning on December 4, 2014, the new KAS will be implemented and candidates with calculated panel reactive antibody (cPRA) values of 98%, 99% and 100% will have the highest priority for local, regional and national sharing, respectively. This approach is projected to improve the access of patients in this group to compatible organs. While the new KAS undoubtedly favors the highly sensitized candidate, antibodies to HLA-DPB and HLA-DQA antigens were not incorporated into the new allocation algorithm and they were not (and could not be) modeled in the simulation performed by the Scientific Registry of Transplant Recipients. The effect of omitting this immunological information may have unintended consequences depending on the frequency of DPB and DQA antibodies among candidates with cPRA of ≥98%. Under the current allocation schema, listing of unacceptable antigens combined with virtual crossmatching has facilitated the transplantation of many highly sensitized patients [1]. Nonetheless, unexpected positive crossmatches still occur as a result of antibodies to DPB and DQA. In order to better understand the potential impact these antibodies may present under the new KAS, we assessed the frequency of antibodies to DPB and DQA among active candidates with cPRA ≥98%. Our findings show that these antibodies are quite prominent among this group of patients and we predict that their presence will result in a less-than-expected rate of transplantation.

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[donor99]

I believe that the new antigens and antibodies will be tested for(it was recently approved by the board.)...if the crossmatch fails the host OPO can bring the kidney back for local allocation. Many DSA's will have blood to do  local crossmatches up front  in the event that the alllocated kidney does not match the sensitized recipient...it can come back to the host OPO for local allocation, with standard kidneys the cold time should not be an issue