Red cell sensitization due to anti-D in anti-lymphocyte globulin.

Four Rh-positive patients with severe aplastic anemia received equine anti-lymphocyte globulin. Each developed a positive direct antiglobulin test. Anti-D was identified in eluates prepared from the patients' sensitized red cells. The administered lot of anti-lymphocyte globulin was found to contain anti-D. Red cell sensitization due to passively acquired Rh antibodies can result from the administration of anti-lymphocyte globulin.