Increased bone marrow iron stores is an independent risk factor for invasive aspergillosis in patients with high-risk hematologic malignancies and recipients of allogeneic hematopoietic stem cell transplantation

BACKGROUND. Invasive aspergillosis (IA) is a leading cause of death in patients with leukemia and those who have undergone hematopoietic stem cell transplantation. Laboratory studies have demonstrated that iron is essential for Aspergillus growth and virulence. METHODS. In the current study, the authors retrospectively evaluated the bone marrow iron stores (BMIS) in patients with leukemia as well as recipients of allogeneic hematopoietic stem cell transplantation with IA (n = 33) and those without fungal infections (n = 33). The first available bone marrow biopsy specimens prior to the IA diagnosis or date of hospitalization (control group) were assessed in a blinded fashion using a standardized scoring system (0-4). Both groups were comparable with regard to clinical characteristics and classic risk factors for IA. RESULTS. The majority of patients with IA (70%) were found to have increased BMIS (score ≥3) compared with the control patients (16%) (P <. 0001). Increased BMIS was found to be an independent risk factor for IA on multivariate analysis (P < .0001). CONCLUSIONS. The prospective validation of BMIS for risk stratification in patients with leukemia or those who undergo allogeneic hematopoietic stem cell transplantation is needed.