A Patient with a High Reticulocyte Count

This patient presents a classic case of severe warm autoimmune hemolytic anemia (WAIHA). Criteria for that diagnosis include evidence of autoantibody directed against the RBCs as well as classic evidence of hemolysis. The former is evident in the form of a positive DAT due to IgG and complement coating of the RBCs. Reactivity with all cells in the antibody identification panel is typical of autoantibodies, although they may show specificity similar to common alloantibodies. The fact that the antibody in the eluate is recovered from a patient who has not been transfused demonstrates that it is auto-reactive, and the fact that the antibody in the serum can be removed by autoadsorption demonstrates this as well. The combination of warmand cold-reactive autoantibodies is relatively common, present in as many as 30% of cases. We typically presume the warm-reactive component causes the hemolysis, but that would be difficult to prove in this case.