Epidemiology and prevention of bacterial infections in patients with hematologic malignancies

Bacterial infections are a serious complication of hematologic malignancies and the therapies used to treat them. Neutropenia can result from the malignancy itself or develop as a complication of chemotherapy and remains a major risk factor for the development of infections in these patients. In addition, the mechanical and chemotherapeutic interventions applied to patients with hematologic malignancies impose additional challenges to host defenses against bacterial invasion. The bacteria responsible for most infections in this patient population have continued to evolve as different therapeutic, preventive, and preemptive strategies are introduced into the armamentarium for leukemias, lymphomas, and myelomas. Both Gram-negative and Gram-positive pathogens have become increasingly resistant to available antimicrobial agents, in part due to the increasing use of agents, especially the fluoroquinolones, to prevent bacterial infections. This review addresses recent clinical developments in the epidemiology and prevention of bacterial infections in these unique populations of patients.