Blood tacrolimus concentrations in bone marrow transplant patients undergoing plasmapheresis.

Microangiopathic hemolytic anemia (MAHA) is a well-described complication of stem cell transplantation. Plasmapheresis is one modality utilized as therapy for patients who develop this complication. However, plasmapheresis may alter whole blood levels of certain medications and its effect on tacrolimus in bone marrow transplant patients is unknown. Because tacrolimus has a narrow therapeutic range, the effect of plasmapheresis on whole blood concentrations would be important to know. We report three allogeneic BMT patients who were receiving tacrolimus as acute GVHD therapy while undergoing plasmapheresis for MAHA. Tacrolimus levels seemed unaffected by plasmapheresis in these patients.