ORAL SESSIONS - Best AbstractsPresence of donor specific antibodies anti-human leukocyte antigen
(HLA) is generally a contra-indication for transplantation and
nowadays the identification of these antibodies are part of most
pre-transplantation evaluations. In Portugal, the implemented protocol
for the registration and maintenance of the active list for
kidney transplant includes a complement-dependent cytotoxity
(CDC) panel-reactive antibody (PRA) screening method, and
Luminex technology for detecting and characterizing HLA alloantibodies.
Under the current Portuguese kidney allocation system
from deceased donors, implemented in August 2007, deceased
donor kidneys are primarily allocated via ABO identical and time
on dialysis with extra points to hyperimmunized patients, namely
PRA CDC>50%. Additional risk for the candidate or transplant
organ can be represented by a proposed calculated PRA (cPRA)
based upon unacceptable HLA antigens detected by Luminex to
which the patient has been sensitized. These unacceptable HLA
antigens used to generate cPRA represents a ‘virtual’ crossmatch
(XM). Sensitized patients are less likely to be matched with a
suitable donor organ. Even after clearing the hurdle of procuring
a living donor, it is still possible that this is not sufficient due to
the likelihood of having a XM-positive. In these cases and in the
presence of incompatible blood type between recipients and their
intended living donors, kidney paired donation (KPD) can provide
an answer by facilitating exchanges between willing donors’ kidneys.
A national Portuguese KPD program, when realized, may
prevent the current loss of a significant number of suitable living
donors and reduce waiting list time for a deceased donor.
An upgrade of a suggested point system in a Portuguese KPD
program will be the use of cPRA instead of the values of PRA
CDC. In Portugal, the virtual XM approach simply represents the
optimization of an existing technique