Positive crossmatches against mandatorily shared kidneys.
From October 1987 through February 1990 approximately 8.5% (29/341) of all donor kidneys shipped under the UNOS Mandatory Sharing Policy were denied to 27 intended recipients due to a positive final crossmatch [XM(+)]. The intended recipients included 18.5% hispanics and 7.4% blacks compared to 2.4% and 1.6%, respectively, for XM(-) recipients (1-3). Further, more were highly sensitized with 81% having a current PRA greater than 10% and 56% with a peak PRA greater than 80% compared to 65% and 14%, respectively, for XM(-) recipients. More importantly, 19/27 (70%) of the recipient candidates may have had irrelevant positive XMs. The XM(+) patients were classified into five categories defined by: I) autoantibodies; II) transfusions in the 2 weeks prior to the availability of the donor; III) the XM technique; IV) highly sensitized regraft candidates with current and peak PRAs greater than 85% and V) antibody to unreported MHC antigens. Of these, 70% may have been denied a transplant due to IgM autoantibodies or the use of XM techniques lacking extensive evaluation. The authors propose that all XM(+) mandatorily-shared kidneys be examined for IgM autoantibody and that kidneys not be denied to potential recipients due to IgM autoantibody. In addition, to minimize exclusions based on positive B-cell XMs, it is proposed that mandatorily-shared kidneys be shared on the basis of the DR subtypes, insofar as is currently practical.
Barger
B O
BO
UAB Regional Histocompatibility Laboratory, University of Alabama, Birmingham 35233.
Fotino
M
M
Zmijewski
C M
CM
LeFor
W M
WM
D006650:Histocompatibility Testing / Q000592:standards*; D006801:Humans; D007518:Isoantibodies / Q000032:analysis; D016030:Kidney Transplantation / Q000276:immunology* / Q000379:methods; D014015:Tissue Banks / Q000592:standards*; D014019:Tissue Donors
D007518:Isoantibodies