Rifaximin for Infection Prophylaxis in Hematopoietic Stem Cell Transplantation

This study is for patients who will be having a blood/marrow transplant (BMT) to treat leukemia, lymphoma or other cancer of the blood. The blood or marrow cells will come from another person (donor)-allogeneic BMT. Bacterial infections and acute graft versus host disease (AGVHD) are frequent complications of allogeneic BMT. Bacterial infections sometimes happen because injury to the gut during transplant allows gut bacteria to cross the injured gut barrier and get to the blood. AGVHD happens when certain white blood cells, called T-cells, in the donor cells (the graft) attack the patient's body. Primary purpose of the study is to see if rifaximin can improve the balance of bacteria within the gut, which has been shown to improve transplant outcomes. It will also assess whether rifaximin can reduce the risk of infection in blood/marrow transplant (BMT).