Autoimmune hemolysis following transfusion: a mimicking autoanti-D in a D– patient with alloanti-D

An 80-year-old group O, D– (rr) female with anti-C, -D, -E, and -Fy^a received four units of crossmatch-compatible red blood cells (RBCs). The direct antiglobulin test (DAT) was negative. Two weeks later, jaundice, dark urine, a 16% drop in hematocrit (Hct), a 20% reticulocyte count, and absent haptoglobin occurred. During the next month, her DAT was positive with anti-IgG and -C3d. Acid eluates, which repeatedly showed anti-D specificity, were nonreactive with enzyme-treated D– RBCs. Adsorption with D– RBCs reduced reactivity. An eluate from the adsorbing D– RBCs was nonreactive with D+ RBCs. These findings suggest an autoantibody mimicking alloanti-D. The patient was treated with prednisone and was transfused with group O, D– (rr), K–, Fy(a–) RBCs. Four months later, the Hct was stable. One year later, the DAT remained positive and the eluate demonstrated a panagglutinin. Immunohematology 1994; 10:117–119.