Graft-versus-host disease and survival after ABO-incompatible allogeneic bone marrow transplantation: a single-centre experience

The effect of ABO-incompatibility on graft versus host disease (GVHD) and survival was evaluated in 173 consecutive patients receiving allogeneic bone marrow transplantation (BMT). Thirty-four percent of the patients developed GVHD and univariate analysis suggested a higher incidence of GVHD in minor ABO-incompatibility than in ABO-identity (14/30, 47% versus 37/112, 33%; P = 0.02). However, using logistic regression adjusted for potential confounders, the GVHD risk did not differ significantly. During a mean follow-up time of 59 months, the mortality was 37% and survival was significantly dependent on ABO-compatibility (P = 0.004). In particular, patients with bidirectional ABO-incompatibility had an excess mortality rate (RR, 7.6; 95% CI, 2.5-23.2; P = 0.0004). Taken together, these results suggest that ABO-incompatibility may represent a risk factor in allogeneic BMT.