Pneumonia in the neutropenic cancer patient

Abstract

Purpose of review Pneumonia is the leading cause of death among neutropenic cancer patients, particularly those with acute leukemia. Even with empiric therapy, case fatality rates of neutropenic pneumonias remain unacceptably high. However, recent advances in the management of neutropenic pneumonia offer hope for improved outcomes in the cancer setting. This review summarizes recent literature regarding the clinical presentation, microbiologic trends, diagnostic advances and therapeutic recommendations for cancer-related neutropenic pneumonia. Recent findings While neutropenic patients acquire pathogens both in community or nosocomial settings, patients’ obligate healthcare exposures result in the frequent identification of multidrug resistant bacterial organisms on conventional culture-based assessment of respiratory secretions. Modern molecular techniques, including expanded use of galactomannan testing, have further facilitated identification of fungal pathogens, allowing for aggressive interventions that appear to improve patient outcomes. Multiple interested societies have issued updated guidelines for antibiotic therapy of suspected neutropenic pneumonia. The benefit of antibiotic medications may be further enhanced by agents that promote host responses to infection. Summary Neutropenic cancer patients have numerous potential causes for pulmonary infiltrates and clinical deterioration, with lower respiratory tract infections among the most deadly. Early clinical suspicion, diagnosis and intervention for neutropenic pneumonia provide cancer patients’ best hope for survival.

Inducible epithelial resistance protects mice against leukemia-associated pneumonia

“…The induction of broad activation of antimicrobial responses is notable, both because leukemia patients are frequently susceptible to pneumonia caused by uncommon pathogens and because the pathogen is often unknown due to inability to obtain a sample, culture-suppressive effects of ongoing antibiotic therapy or technical inability to detect obscure pathogens. [15][16][17] Thus, not only do the current studies suggest that inducible epithelial resistance is likely to persist in profoundly immunocompromised, neutropenic leukemia patients, but they also indicate that this strategy is likely to benefit patients in a manner that does not depend on pathogen identification. This broad protection bears some conceptual similarity to trained innate immunity in monocytes, macrophages, and natural killer cells.…”

“…Chemotherapy-associated neutropenia, although both the most frequent and important risk factor for pneumonia in this population, is only one of many immune defects observed in AML/MDS patients. [15][16][17] Because of the complex leukocyte defects observed in these patients, our laboratory has sought alternate means to protect them from pneumonia during periods of peak vulnerability. We demonstrate here that the strategy of therapeutically manipulating responses from epithelial cells is efficacious in protecting mice from pneumonia, despite the presence of leukemia cells and/or common leukemia therapy.…”

“…Leukemia patients frequently present with complex leukocyte defects, often arising from both multilineage cytopenias and functional impairments of chemotaxis, diapedesis, and pathogen killing. [15][16][17] Thus, therapeutic manipulation of lung parenchymal cells might present an opportunity to protect patients against pneumonia without reliance on the cells most negatively impacted by disease and treatment.…”

Bacterial Pneumonia in Patients with Cancer

“…Pneumonias are estimated to cause or complicate nearly 10% of hospital admissions among cancer patients, notably including patients with hematologic malignancies whose estimated risk of pneumonia during the course of treatment exceeds 30% [3, 5-8]. In fact, in the transfusion era, pneumonia is the leading cause of death among patients with acute leukemias [3, 9, 10]. Some investigations suggest that as many as 80% hematopoietic stem cell transplant (HSCT) recipients will experience at least one episode of pneumonia, and pneumonia is the proximate cause of death in 20% of HSCT patients [11-13].…”

Colonization of Streptococcus pneumoniae in Pneumonia Patients with Lung Cancer

“…Pneumonia accounts for higher morbidity and mortality than any other infections in cancer patients (11)(12)(13)). An estimated 10% of the hospital admissions for the treatment of cancer was complicated due to pneumonia and it exceeds up to 30% in patients with hematological malignancies (14)(15)(16)(17). Cancer patients are highly susceptible to severe pneumococcal infections and Streptococcus pneumoniae was the most common pathogen found among them (18).…”