IMMUNOHEMATOLOGIC SURVEY DURING ABO-INCOM PATIBLE BONE-MARROW TRANSPLANTATION

Direct an antiglobulin test (DAT), ABO typing and isoagglutinins titer s were regularly performed in 26 patients who received a marrow transp lant from a major ABO incompatible donor (M = 10 cases), from a minor ABO incompatible donor (m = 10 cases) or both (B = 6 cases). Erythrocy te or plasma depletion of bone marrow infusate was used in all major o r certain minor ABO incompatibilities respectively. A positive DAT was recorded in 19/26 patients at various times, but only a few of them, belonging to groups M or B, exhibited a significant hemolysis. No seri ous complication was observed after bone marrow infusion. Five patient s showed evidence of hemolysis after transplantation, 1 patient died w ith a graft rejection and 3 patients had a delayed erythropoietic engr aftment. In all cases of major ABO incompatibility, the erythrocyte re covery was preceeded by a decrease of antibodies against the donor's b lood group. These antibodies finally disappeared in all patients excep t one who had a persistence of isoagglutinins beyond day + 650. A tran sient appearance of isoagglutinins against the recipient blood group w as sometimes detected in minor ABO incompatibility without any clinica l complications.