Incidence and pattern of hemolytic anemia after minor ABO-mismatched living-donor lobar lung transplantation

Living-donor lobar lung transplantation (LDLLT) has been successfully performed in Japan. In LDLLT, the recipient usually receives one lower lobe from each of two donors; however, finding two ABO-matched donors is often difficult. Solid organ transplants from donors with minor ABO-mismatches can be complicated by hemolysis. We investigated the incidence of de novo anti-ABO antibody production and hemolysis in patients receiving LDLLT across minor ABO-mismatches. We evaluated 23 patients who underwent LDLLT between June 2008 and December 2011, including 11 patients who underwent minor ABO-mismatched transplantation. We measured the anti-A/B antibody serum titers, hemoglobin concentrations and indirect bilirubin levels. None of the patients showed any clinical signs of hemolytic anemia (mean follow-up period; 16 months). Two of the 11 patients (18 %) receiving minor ABO-mismatched LDLLTs showed a small amount of de novo anti-B antibodies for a transient period. These patients showed gradual progression of anemia, and weak de novo anti-A/B antibodies were detected with column agglutination technology. The patients received only 2 U of washed type O red blood cells; thereafter, the hemolytic anemia did not develop further in either case. LDLLT across minor ABO-mismatches results in the transient appearance of weak de novo anti-A/B antibodies with a low incidence; thus, this procedure can be a safe treatment.