FATAL OUTCOME IN A PATIENT WITH AUTOIMMUNE HEMOLYTIC-ANEMIA ASSOCIATED WITH AN IGM BITHERMIC ANTI-(IP)-P-T

Background: Several cold autoantibodies (usually IgG) with I-T specifi city have been reported previously, as have autoantibodies with joint I and P blood group specificities (IP1, (IP1)-P-T, iP(1), IP). A fatal outcome associated with an IgM cold autoantibody of (IP)-P-T specific ity is reported. Case Report: A 54-year-old man suffered from progress ively severe cold autoimmune hemolytic anemia for 9 months. Hemoglobin concentration ranged from 6 to 7 g per dL (60-70 g/L) and reticulocyt es from 3 to 5 percent (0.030-0.050). The direct antiglobulin test was weakly positive for IgM and strongly positive for C3d. The serum cont ained a cold agglutinin that reacted strongest with cord i red cells ( RBCs) >adult I RBCs >adult i RBCs, which is consistent with I-T specif icity. The Donath-Landsteiner test was positive; the reaction was neut ralized by globoside. The serum reacted weakly or was negative with RB Cs from five group p blood donors, which suggests anti-(IP)-P-T specif icity. Dithiothreitol treatment of the serum abolished the cold agglut inin reactivity, which suggests that the anti-I-T was IgM. The patient received >40 RBC transfusions and failed to respond to oral steroids, oral cytoxan, high-dose pulse intravenous steroids, and plasma exchan ge at room temperature and at 35 degrees C. He died of sepsis followin g an unsuccessful trial of chlorambucil. Autopsy revealed unsuspected disseminated non-Hodgkin's lymphoma. Conclusion: Serologic studies are consistent with our patient's having a single IgM cold autoantibody w ith I-T and P specificities (anti-(IP)-P-T) and requiring both specifi cities on the same RBC to permit maximal antibody expression.