Background Bloodstream infection (BSI) is a constant threat for hospitalized patients, and elderly patients are particularly susceptible to BSI caused by anaerobic bacteria. Changes in the gut microbiota composition may lead to pathogen overgrowth and translocation into the bloodstream. Consequently, domination of specific taxa in the intestinal bacterial community seems to be associated with a higher risk of bacteremia in some patient populations. Case presentation Here, we report the case of a 90-year-old heart failure (HF) patient who was admitted to the hospital for an acute state of cardiac decompensation. Twenty days after admission, he was febrile to 38.2 °C whereas his white blood count and C-reactive protein increased to 6190 cells/μL and 31.2 mg/L, respectively. Of the patient's blood culture (BC) bottle pairs collected under the suspicion of infection, the anaerobic bottle yielded an organism that was later identified as Prevotella copri. Concomitantly, the patient's fecal sample was obtained for the intestinal microbiota characterization by sequencing the V3/V4/V6 regions of the bacterial 16S rRNA gene. The analysis revealed highest relative abundances of Bacteroidales (34.1%), Prevotellaceae (19.0%), Prevotella (15.2%), and P. copri (6.1%) taxa, indicating that the patient's gut microbiota was dominated by Prevotella organisms. The patient was successfully treated with metronidazole, and was discharged to a long-term care facility at 35 days of admission. Conclusions We provide the first evidence for a clinically significant BSI caused by P. copri and its relationship to a Prevotella-rich gut microbiota in the HF patient setting. When strengthening the pathogenicity of P. copri, the present case suggests that the gut may be a source of BSI caused by the rare anaerobic organism. Future studies are necessary to assess the role of the gut microbiota profiling for precise identification and targeted treatment of patients at high risk of BSI.

中文翻译：

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由普氏菌引起的首例血液感染，导致一名以普氏菌为主的老年心力衰竭患者的肠道微生物群：病例报告。

背景血流感染（BSI）是住院患者的持续威胁，老年患者特别容易受到厌氧菌引起的BSI。肠道微生物群组成的变化可能导致病原体过度生长并转移到血液中。因此，肠道细菌群落中特定分类群的优势似乎与某些患者人群中较高的菌血症风险有关。病例介绍 在此，我们报告了一名 90 岁的心力衰竭 (HF) 患者，该患者因急性心脏失代偿而入院。入院 20 天后，他发热至 38.2 °C，而他的白细胞计数和 C 反应蛋白分别增加到 6190 个细胞/μL 和 31.2 mg/L。病人的' 在怀疑感染下收集的 s 血培养 (BC) 瓶对，厌氧瓶产生了一种有机体，后来被确定为普氏菌。同时，通过对细菌 16S rRNA 基因的 V3/V4/V6 区域进行测序，获得了患者的粪便样本用于肠道微生物群的表征。分析显示，拟杆菌门 (34.1%)、普氏菌科 (19.0%)、普氏菌属 (15.2%) 和 P. copri (6.1%) 类群的相对丰度最高，表明患者的肠道微生物群以普氏菌属微生物为主。患者用甲硝唑成功治疗，并在入院 35 天后出院到长期护理机构。结论 我们提供了第一个证据证明由 P. copri 及其与 HF 患者环境中富含普雷沃氏菌的肠道微生物群的关系。在加强 P. copri 的致病性时，本案例表明肠道可能是由稀有厌氧生物引起的 BSI 的来源。未来的研究对于评估肠道微生物群分析在精确识别和靶向治疗 BSI 高风险患者中的作用是必要的。