Table_1_Pathogenic spectrum and drug resistance of bloodstream infection in patients with acute myeloid leukaemia: a single centre retrospective study.docx

BackgroundBloodstream infection (BSI) represent a prevalent complication in haematological malignancies (HMs). Typically, Patients with BSI usually undergo empirical treatment pending pathogen identification. The timely and effective management of BSIs significantly influences patient prognosis. However, pathogen distribution in BSIs exhibits regional variation. In this study, we investigated the clinical characteristics, pathogen spectrum, drug resistance, risk factors of short-term prognosis and long-term prognostic factors of acute myeloid leukemia (AML) patients with BSI at Zhejiang Provincal People’s Hospital.
MethodsFrom 2019 to 2021, a total of 56 AML patients with BSI were treated in the Department of Haematology at Zhejiang Province People’s Hospital. Data regarding pathogen spectrum and drug resistance were collected for analysis. The patients were stratified into non-survivor cohort and survivor cohort within 30 days after BSI, and the predictors of 30-days mortality were identified through both univariate and multivariate Logistic regression analyses. Furthermore, Kaplan-Meier survival analysis and Cox regression analysis were employed to ascertain the risk factors associated with poor prognosis in AML patients complicated by BSI.
ResultsA total of 70 strains of pathogenic bacteria were isolated from 56 AML patients with BSI. Gram-negative bacteria constituted the predominant pathogens (71.4%), with Klebsiella pneumoniae being the most prevalent (22.9%). Gram-positive bacteria and fungi accounted for 22.9% and 5.7%, respectively. Univariate and multivariate analyses revealed significant differences in total protein, albumin levels, and the presence of septic shock between the non-survivor cohort and the survior cohort 30 days post-BSI. COX regression analysis showed that agranulocytosis duration exceeding 20 days (HR:3.854; 95% CI: 1.451–10.242) and septic shock (HR:3.788; 95% CI: 1.729–8.299) were independent risk factors for poor prognosis in AML patients complicated by BSI. Notably, the mortality rate within 30 days after Stenotrophomonas maltophilia infection was up to 71.4%.
ConclusionsIn this study, Gram-negative bacteria, predominantly Klebsiella pneumoniae, constituted the primary pathogens among AML patients with BSIs. Serum albumin levels and the presence of septic shock emerged as independent risk factors for mortality within 30 days among AML patients with BSI. In terms of long-term prognosis, extended agranulocytosis duration exceeding 20 days and septic shock were associated with elevated mortality rates in AML patients with BSI. Additionally, in our centre, Stenotrophomonas maltophilia infection was found to be associated with a poor prognosis. Early intervention for Stenotrophomonas maltophilia infection in our centre could potentially improve patient outcomes.

背景 血流感染（Bloodstream Infection, BSI）是血液系统恶性肿瘤（Haematological Malignancies, HMs）患者常见的并发症。通常，血流感染患者在明确病原体前需接受经验性治疗。血流感染的及时有效管理对患者预后具有显著影响。然而，血流感染的病原体分布存在地域差异。本研究针对浙江省人民医院收治的急性髓系白血病（Acute Myeloid Leukemia, AML）合并血流感染患者，分析其临床特征、病原体谱、耐药性、短期预后危险因素及长期预后影响因素。方法 2019年至2021年，浙江省人民医院血液内科共收治56例合并血流感染的急性髓系白血病患者。收集其病原体谱及耐药性相关数据进行分析。以血流感染发生后30天为界，将患者分为存活组与非存活组，通过单因素及多因素Logistic回归分析明确30天死亡率的预测因素。此外，采用Kaplan-Meier生存分析及Cox回归分析，明确合并血流感染的急性髓系白血病患者不良预后的相关危险因素。结果 本研究从56例合并血流感染的急性髓系白血病患者中共分离出70株病原菌。革兰阴性菌为主要病原体（占比71.4%），其中肺炎克雷伯菌最为常见（占比22.9%）。革兰阳性菌与真菌占比分别为22.9%与5.7%。单因素及多因素分析显示，血流感染后30天的非存活组与存活组在总蛋白水平、白蛋白水平及感染性休克发生率方面存在显著差异。Cox回归分析显示，粒细胞缺乏持续时间超过20天（风险比HR=3.854，95%置信区间CI：1.451~10.242）及感染性休克（HR=3.788，95%CI：1.729~8.299）是合并血流感染的急性髓系白血病患者不良预后的独立危险因素。值得注意的是，嗜麦芽窄食单胞菌感染患者的30天死亡率高达71.4%。结论 本研究显示，合并血流感染的急性髓系白血病患者的主要病原体为革兰阴性菌，其中以肺炎克雷伯菌为主。血清白蛋白水平及感染性休克的发生是合并血流感染的急性髓系白血病患者30天死亡率的独立危险因素。就长期预后而言，粒细胞缺乏持续时间超过20天及感染性休克与合并血流感染的急性髓系白血病患者的死亡率升高相关。此外，本中心数据显示，嗜麦芽窄食单胞菌感染与不良预后相关。本中心针对嗜麦芽窄食单胞菌感染的早期干预或可改善患者预后。