Flow cytometry crossmatch before kidney transplantation in contemporary practice: target cell utilization, results patterns, and associated long-term graft survival.

Krista L. Lentine, Ralph J. Graff, Huiling Xiao, Kian A. Modanlou, Paolo R. Salvalaggio, Daniel Brennan, Brett W. Pinsky, Thomas E. Burroughs, Mark A. Schnitzler

Research output: Contribution to journalArticle


The flow cytometry crossmatch (FXCM) is an increasingly common method for pre-transplant crossmatching. We examined FCXM use in a national sample of kidney transplants, characterizing target cell utilization, results patterns, and associated graft outcomes. We queried Organ Procurement and Transplant Network Registry to identify kidney transplants performed in 1995-2007 with prospective FCXM testing for IgG antibodies against T-cells, B-cells or undifferentiated lymphocytes. FCXM was categorized according to target utilization and target-specific results. We modeled associations of FCXM testing-results patterns with risk of five-year graft loss and with projected graft survival by multivariable survival analysis. Sixty-five percent of the deceased donor transplants were performed with negative T-cell and B-cell FCXM, 16% with negative T-cell/unmeasured B-cell FCXM, 9% with negative undifferentiated lymphocyte FCXM, and < 0.5% with negative B-cell/unmeasured T-cell FCXM. Test results for at least one target were positive in 7.6% of transplants, most commonly in the form of B-cell positive/T-cell negative. Allograft survival was most favorable when both T-cell and B-cell FCXM targets were included and yielded negative results. Notably, B-cell positive/T-cell negative FCXM predicted elevated graft loss risk, with approximately 16% and 32% relative risk increases for deceased and living donor grafts, respectively, compared to negative T-cell and B-cell FCXM. Negative FCXM results with undifferentiated targets alone also predicted inferior graft survival. These data support the importance of using differentiated B-cell and T-cell targets for FCXM. Transplants that proceeded with positive FCXM experienced decrements in long-term graft survival - the decision to accept such risk must be individualized.

Original languageEnglish (US)
Pages (from-to)253-266
Number of pages14
JournalClinical transplants
Publication statusPublished - Dec 1 2008
Externally publishedYes


ASJC Scopus subject areas

  • Medicine(all)

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