TMA Can Be Overlooked in Some Stem Cell Patients, Requires Specific Treatment

Published March 23, 2017
The New England Journal of Medicine

As many as 30 percent of children and young adults receiving hematopoietic stem cell transplants develop thrombotic microangioplasty (TMA) in the weeks following transplant. However, the condition can be overlooked and go untreated because it frequently occurs alongside graft-versus-host disease (GVHD), according to blood disease experts at Cincinnati Children’s.

A correspondence co-authored by Seth Rotz, MD, Christopher Dandoy, MD, and Stella Davies, MB, BS, PhD, all members of the Division of Bone Marrow Transplant and Immune Deficiency, outlines the potentially dangerous risk of overlooking TMA.

“In our clinical experience, specific treatment of both transplant associated TMA and GVHD is needed for full resolution of symptoms when both disease processes are present,” the authors wrote.

If left unchecked, TMA can cascade from anemia and platelet consumption to thrombosis and, in some children, multiple organ failure and death. Cincinnati Children’s is the only center in the U.S. that performs the full array of molecular and cellular diagnostic testing for TMA.

The authors state that elevated levels of the ST2 protein, a marker of endothelial injury, can be associated with both GVHD and TMA. However, immune suppression therapy that can treat GVHD has no effect on TMA.

The correspondence recommends that patients who appear to have glucocorticoid-resistant GVHD also be carefully evaluated for signs of TMA.

Previous research led by scientists at Cincinnati Children’s (published July 24, 2014, in Blood) indicates that eculizumab, a humanized monoclonal antibody that functions as a terminal complement inhibitor, shows promise as a therapy for transplant-related TMA.