Microorganisms Cultured from Sputum and Blood in Association with Episodes of Fever During anti-cancer Therapy in Patients with Lung Cancer

We examined the clinical features and significance of pathogenic microbes isolated from sputum and blood of patients with lung cancer during anti-cancer therapy. Pathogenic bacteria were more likely to be isolated from patients with episodes of fever than from afebrile patients. The major species of bacteria isolated from sputum were Staphylococcus aureus, including methicillin-resistant strains, and Gram-negative bacilli, which are known to be frequently involved in hospital-acquired infections. The presence of an indwelling central venous catheter for intravenous hyperalimentation was an important risk factor for the development of a febrile episode, which indicates that bacteremia was a major cause of fever. In one quarter of the blood cultures from the patients with persistent fever, various species of pathogenic microbes were recovered, one-third of which were fungi. Bacteriological examinations done before and after the introduction of granulocyte-colony stimulating factor (G-CSF) revealed that strains of Klebsiella spp. decreased and those of methicillin-resistant S. aureus increased. There was no firm evidence that G-CSF decreased the incidence of episodes of fever. However, remains G-CSF may a allow the dose intensity of anti-cancer agents to be increased, which would lead to severe leukocytopenia. However, more detailed investigation is needed to clarify the role of G-CSF against bacterial infection during anti-cancer therapy.