LONG-TERM IMPROVEMENT OF GRAFT SURVIVAL IN CADAVERIC RENAL RETRANSPLANTATION BY FLOW CYTOMETRIC CROSSMATCHING

Abstract

456 In 1990, six of the seven renal transplant centers for which our histocompatibility laboratory performs flow cytometric crossmatches prospectively began using a positive flow crossmatch as an exclusion criteria for cadaveric renal retransplantation, while one center continued to use only the AHG T cell IgG crossmatch through 1995. The purpose of this study was to evaluate the long-term outcome of cadaveric retransplants comparing flow crossmatch-selected patients (n=106) all done from 1990 to 1997 with two groups of patients. The first was 174 regraft patients who were selected only by the AHG crossmatch from 1985 to 1995. It should be noted that all centers used the AHG crossmatch for regrafts from 1985 to 1989, but from 1990 through 1995, only one center continued selection only by the AHG technique. The second group was primary cadaveric transplants done from 1990 to 1997 (n=889), all of whom were selected by the AHG crossmatch. The data in the followingtable show the long-term outcome for regraft patients, by flow and AHG crossmatch selection criterion, and primary cadaveric transplants.These data show that long-term allograft survival of flow crossmatch-selected cadaver regrafts is equivalent to that of concurrent primary transplants (log-rank=0.20) and is better than AHG crossmatch-selected regrafts (log-rank=0.001). Finally, long-term (6 year) graft outcome was not influenced by a positive B cell flow crossmatch (67%; n=37) compared with that of a negative B cell flow crossmatch (77%; n=60) (log-rank=0.69). In conclusion, use of the flow T cell IgG crossmatch in the exclusion criteria for cadaver renal retransplantation yields improved long-term graft survival over that of the AHG crossmatch. A positive B cell flow crossmatch, however, has no significant influence on long-term graft outcome in cadaver renal retransplantation.