Barreto, Jason N.

Bone marrow is a complex organ responsible for the regulation of hematopoietic cell distribution throughout the human body. Patients receiving antineoplastic agents as a therapeutic intervention for hematologic malignancy often experience varying degrees of myelotoxicity. Antineoplastic agents cause hypocellularity in marrow resulting in a reduction in hematopoietic tissue activity and a corresponding decline in cell production. Quantifying the adverse effects on hematopoiesis is based on the properties of a single agent, the use of individual drugs within a combination chemotherapy regimen, and the course, or courses, of chemotherapy designed to treat cancer. The direct or indirect suppression of erythrocytes, granulocytes, and megakaryocytes has potential for multiple negative clinical consequences ranging from increased monitoring of blood counts to life-threatening infection and death. This review will provide an overview of the structure and function of competent adult bone marrow, describe the process of hematopoiesis, and characterize the myelotoxicities associated with common antineoplastic agents currently used in the treatment of cancer.

ABSTRACT Rothia spp. are Gram-positive cocco-bacilli that cause a wide range of serious infections, especially in immunocompromised hosts. Risk factors for Rothia mucilaginosa (previously known as Stomatococcus mucilaginosus ) bacteremia include prolonged and profound neutropenia, malignancy, and an indwelling vascular foreign body. Here, we describe 67 adults at the Mayo Clinic in Rochester, MN, from 2002 to 2012 with blood cultures positive for Rothia . Twenty-five of these patients had multiple positive blood cultures, indicating true clinical infection. Among these, 88% (22/25) were neutropenic, and 76% (19/25) had leukemia. Common sources of bacteremia were presumed gut translocation, mucositis, and catheter-related infection. One patient died with Rothia infection. Neutropenic patients were less likely to have a single positive blood culture than were nonneutropenic patients. Antimicrobial susceptibility testing was performed on 21% of the isolates. All of the tested isolates were susceptible to vancomycin and most beta-lactams; however, four of six tested isolates were resistant to oxacillin. There was no difference between the neutropenic and nonneutropenic patients in need of intensive care unit care, mortality, or attributable mortality.

The objective of this study is to characterize the outcomes of primary antifungal prophylaxis with voriconazole in patients receiving intensive chemotherapy for acute myelogenous leukemia (AML) or myelodysplastic syndromes (MDS). We conducted a single center, retrospective, cohort study of consecutive adult patients with AML or MDS at Mayo Clinic between January 1, 2006 and July 1, 2010. The study included patients undergoing induction or first relapse combination chemotherapy who received voriconazole 200 mg orally twice daily as prophylaxis during the neutropenic phase. Patient records were evaluated until 30 days after neutrophil recovery for development of invasive fungal infection (IFI) as defined per EORTC/MSG 2008 criteria with computed tomography scans independently reviewed by a radiologist. Therapeutic drug monitoring and reasons for voriconazole discontinuation were documented. Twenty four episodes of IFI were detected among 165 consecutive patients for an overall incidence of 145 per 1000 patients. The incidence of IFI was 24, 42, and 78 per 1000 patients for proven, probable, and possible infection, respectively. Four patients developed proven IFI (n = 2 Aspergillus spp., n = 2 Rhizopus spp.). Serum voriconazole trough concentrations were available in 39 patients, and no statistically significant difference in voriconazole trough level was observed between those with versus without an IFI. Voriconazole prophylaxis was discontinued in 81 patients due to suspected IFI (n = 24), fever of unknown origin (n = 19), adverse events (n = 23), and other causes (n = 17). Voriconazole as primary IFI prophylaxis is safe and may be beneficial in AML/MDS patients receiving intensive chemotherapy. Am. J. Hematol. 88:283–288, 2013. © 2013 Wiley Periodicals, Inc.