Inhibition of bacteremia in cancer patients with chemotherapy by regulating circadian rhythms

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K17927
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 54030:Infectious disease medicine-related
• Research Institution: Kagawa University
• Principal Investigator: Uemura Makiko 香川大学, 医学部, 助教 (00710188)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 体内時計 / 概日リズム / 時計遺伝子 / 日内変動 / がん化学療法 / 菌血症 / 好中球減少 / 発熱性好中球減少症

Outline of Final Research Achievements

The hypothesis of this study was that “patients undergoing cancer chemotherapy have impaired circadian rhythms, and correcting them can suppress the onset of bacteremia and improve the prognosis.” In the first study, we comprehensively analyzed cases of bacteremia in chemotherapy patients and found a bacteriological relationship between oral commensal bacteria and bacteremia. It was found that about half (46.2%) of cases of bacteremia in patients undergoing chemotherapy were of oral bacterial origin. In addition, we developed and established a model to predict the relationship between the degree of neutropenia and subsequent fever episodes in patients with fever undergoing chemotherapy using the neutropenia index. There was no clear association between the onset time of bacteremia and the subsequent clinical course, and the association between circadian rhythms and bacteremia was not fully elucidated.

Free Research Field

臨床腫瘍学

Academic Significance and Societal Importance of the Research Achievements

本研究において、概日リズムと菌血症の予後の関連は明確とはならなかったが、臨床管理上の理由を除いても、夜間の発症と日中の発症とでは菌血症の生物学的および免疫学的反応性が異なるではないかということが推察された。明確な関連性や影響する要因を抽出するにはさらなる臨床経過の観察および臨床感染症の観点から免疫学的評価およびモニタリングが必要であると考えられた。