Factors predisposing to bacteremia in bone marrow transplant recipients

Factors predisposing to bacteremia associated with bone marrow transplantation were studied prospectively. In 256 bone marrow transplant (BMT) recipients from 1991-96, there were 75 patients with 80 episodes of bacteremia. Among all bacterial isolates, 68% were Gram positive bacteria. During the pre-engraftment period, the infective focus was identified only in 5% of the cases. The only significant risk factor associated with bacteremia was late stage underlying disease (71% of patients, P<0.05). Other factors, including mucositis, severity of conditioning toxicity, and duration and severity of neutropenia or monocytopenia, were not associated with bacteremia. In 53% of cases, the focus of infection could be identified during the post-engraftment period. Hickman catheter infection and severe acute and chronic graft versus host disease (GVHD) were independently associated with bacteremia by multivariate analysis (P<0.001, <0.005 and <0.05 respectively). The risk factors for bacteremia in BMT recipients are therefore different from other cancer patients receiving chemotherapy. Thus, in light of these results, early selective use of hematopoietic growth factors in patients with late stage underlying malignancies during pre-engraftment, antimicrobial prophylaxis for acute GVHD with intense immunosuppression, and intravenous immunoglobulin therapy for chronic GVHD may be helpful.