Thrombotic microangiopathy following allogeneic bone marrow transplantation

Thrombotic microangiopathy is one of the complications of bone marrow trans plantation and is related to other complications such as graft-versus-host disease, veno-occlusive disease, diffuse alveolar hemorrhage, and cytomegal ovirus infection. Thrombotic microangiopathy occurred in three out of 12 pa tients who underwent allogeneic bone marrow transplantation over the past 1 year at our department. We compared the changes in cytokines and other mol ecules between patients with and without microangiopathy from before condit ioning to the early post-transplantation period. All three patients with mi croangiopathy showed a significant increase of interleukin-12 at the time o f leukocyte recovery after transplantation (two-way layout analysis of vari ance; P < 0.05), while none of the patients without microangiopathy showed an increase of interleukin-12. No significant differences were found betwee n the two groups with respect to the other cytokines and molecules that wer e tested. These findings suggested that thrombotic microangiopathy might be predicted at an early stage after bone marrow transplantation by detecting an increase of interleukin-12 at the time of leukocyte recovery. The possi bility that thrombotic microangiopathy is related to inflammation or autoim munity was also suggested.