Yoav Golan, MD, MS, FIDSA, attending physician and associate professor of medicine at Tufts University School of Medicine, Boston, MA, addresses antibacterial prophylaxis and the treatment of febrile neutropenia in acute myeloid leukemia (AML).
Individuals with acute myeloid leukemia (AML) are at high risk for bacterial infection due to their disease and the absence of a functioning immune system to help cope with infections. These patients are often unable to mount an effective immune response to infections. Many general signs of infection that are typically detected in an immunocompetent population are not present in those with AML. It is easy to miss pneumonias on chest X-rays or urinary tract infections in urinalysis when patients are unable to produce these signs, says Yoav Golan, MD.
The consensus in treatment guidelines for neutropenic fever is to initiate therapy as early as neutropenic fever is documented. Treatment should provide coverage for Pseudomonas, Methicillin-resistant Staphylococcus aureus (MRSA), and all suspected pathogens based on patient presentation.
It is essential to consider bacteria that normally reside on the skin in neutropenic fever, notes Golan, as these bacteria gain access to the blood stream through vascular catheters that are left in place for extended periods of time. Patients with AML are also susceptible to bacteria commonly found in the gastrointestinal tract and upper airways, as their chemotherapy medications disrupt the integrity of these mucosal surfaces.
High-risk AML is defined as individuals who are expected to have severe neutropenia (an absolute neutrophil count of less than 100 cells/mL) that persists for at least one week. Antibacterial prophylaxis is given to all patients who have high-risk AML, which includes the majority of this patient population due to standard AML chemotherapy regimens. Patients without those risk factors can be carefully monitored without the initiation of antibacterial prophylaxis.
Antibacterial prophylaxis should begin with the administration of extensive chemotherapy before patients become neutropenic, explains Golan. At most institutions, prophylaxis will continue for another week following the resolution of neutropenia. Commonly recommended agents used in prophylaxis are oral fluoroquinolone antibiotics, such as ciprofloxacin or levofloxacin.