Association of Alemtuzumab Induction With a Significantly Lower Incidence of GVHD Following Intestinal Transplantation: Results of 445 Consecutive Cases From a Single Center

BACKGROUND: In intestinal transplantation, graft versus host disease(GVHD), while relatively rare, remains as a major cause of morbidity and mortality posttransplant. Due to its rarity of occurrence, no multivariable analysis of risk factors for GVHD development has previously been reported. METHODS: We used Cox stepwise regression to determine the significant multivariable predictors of the hazard rate of developing biopsy-proven GVHD during the first 60mo posttransplant among 445 consecutive intestinal transplant cases at our center since 1994. RESULTS: GVHD was observed in 8.8%(39/445); median time-to-GVHD development (range) was 1.5mo (0.5-17.3mo) posttransplant. Sites of GVHD included: skin(N=21), skin/GI(N=6), GI/rectum(N=4), skin/liver(N=4), skin/lung(N=2), skin/rectum(N=1), and skin/bone marrow(N=1). Three factors were selected into the Cox model offering significant protection from GVHD development (listed in order of selection): Isolated Intestine(I) or Liver-Intestine(LI) (vs. Modified Multivisceral(MMV) or Multivisceral(MV)) Allograft (P=0.00003), Alemtuzumab (vs. No Induction, Anti-CD25, rATG, or rATG/Rituximab) Induction (P=0.004), and Liver Inclusion(LI or MV) (P=0.009). These results remained unchanged even after accounting for the propensity-to-receive alemtuzumab induction. Observed GVHD incidence was 2.4%(3/125), 0.0%(0/38), 17.9%(7/39), and 11.9%(29/243) for I, LI, MMV, and MV allografts, and 2.7%(3/113) vs. 10.8%(36/332) for those receiving vs. not receiving alemtuzumab induction, respectively. CONCLUSIONS: These results may help advance the current state of knowledge about risk factors for GVHD development following intestinal transplantation.