Underutilization of A2 ABO incompatible kidney transplantation.
BACKGROUND
ABO compatibility creates a disadvantage for O and B renal allograft candidates. A2 ABO incompatible transplant may decrease waiting times and generate equivalent graft survival to an ABO compatible transplant.


METHODS
Death-censored graft survival was compared between A recipients and O, B, and AB recipients of an A2 allograft with multivariate Cox regression models utilizing data from the United Network of Organ Sharing (UNOS) between 1997 and 2007.


RESULTS
Eighty-five percent of A2 kidneys were transplanted into ABO compatible recipients vs. 15% into ABO incompatible recipients. Rates of A2 incompatible kidney transplants did not increase over the study period (14.8% to 14.6%). Mean wait time for A2→O kidneys was 337 vs. 684 d for O→O and for A2→B kidneys, 542 vs. 734 d for B→B. Adjusted relative risk of graft loss at five-yr was similar between O, B, and AB recipients compared to A recipients of an A2 allograft, corresponding to a five-yr graft survival of 84%, 86.2%, 86.1%, and 86.1%, respectively.


CONCLUSIONS
A2 incompatible kidney transplantation is underutilized. Graft outcomes are similar among A2 compatible and incompatible recipients. Shorter waiting time and improved access might be achieved if A2 kidneys are considered in all blood groups.
Division of Transplant Surgery, Department of Surgery, Hospital of University of Pennsylvania, Philadelphia, PA 19104, USA.
Robert R
RR
Redfield
Ronald F
RF
Parsons
Eduardo
E
Rodriguez
Moiz
M
Mustafa
James
J
Cassuto
Kumar
K
Vivek
Hooman
H
Noorchashm
Ali
A
Naji
Matthew H
MH
Levine
Peter L
PL
Abt
D000017:ABO Blood-Group System / Q000276:immunology*; D000328:Adult; D001787:Blood Group Incompatibility / Q000276:immunology*; D005260:Female; D005500:Follow-Up Studies; D006085:Graft Survival / Q000276:immunology*; D006801:Humans; D007676:Kidney Failure, Chronic; D016030:Kidney Transplantation / Q000276:immunology* / Q000401:mortality / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D014019:Tissue Donors; D009927:Tissue and Organ Procurement; D014181:Transplantation Immunology
D000017:ABO Blood-Group System