The bacteria which were detected by blood culture of 2015-2017: Mouth care and bacteremia during anticancer therapy

Abstract

Introduction: Recent evidence demonstrates that gram-positive bacteria are commonly found in patients with febrile neutropenia, and that this is caused by translocation of the bacteria from the intestinal tract. At the Innovative Cancer Center of our institution, we found that Escherichia coli and Streptococcus mitis/Streptococcus oralis are commonly found in blood cultures, in addition to Staphylococcus epidermidis. Objective: Our aim was to determine the types of bacteria found in blood cultures of patients receiving anti-cancer treatments in order to better define strategies for infection prevention and for selecting appropriate antibiotics. Methods: Blood cultures collected from inpatients at our hospital between April 2015 and March 2018 were analyzed to determine the presence of bacterial species. Results: E. coli was the most common bacteria found in patients with solid cancers. On the other hand, S. epidermidis was the most common bacteria in patients with hematologic cancer, followed by E. coli and S. mitis/S. oralis. S. mitis and S. oralis were detected on and after the day of oral care in these patients. Discussion: There was a difference in the prevalence of the types of bacterial species found in patients with solid cancers compared with those with hematologic cancers. Specifically, S. epidermidis was more prevalent in patients with hematologic cancers than those admitted within other departments of our institution. These findings suggest that infection in these patients may have occurred due to contamination of a sample and/or via the infusion site. We also demonstrated that the prevalence of oral bacteria was high in patients with hematologic cancers. Thus, it is necessary to re-examine the practice of antibiotic prophylaxis during oral care, especially the type of antibiotics and the duration of the treatment.