Corcione Silvia, Longo Bianca Maria, Rugge Walter, De Benedetto Ilaria, Lupia Tommaso, Shbaklo Nour, Zompi Sofia, Gill Jessica, Curtoni Antonio, Passera Roberto, Busca Alessandro, Bruno Benedetto, De Rosa Francesco Giuseppe
Department of Medical Sciences, University of Torino, Torino, Italy.
School of Medicine, Tufts University, Boston, MA, United States.
Front Microbiol. 2025 Aug 7;16:1596900. doi: 10.3389/fmicb.2025.1596900. eCollection 2025.
Bloodstream infections (BSIs) are a serious threat for patients undergoing allogenic hematopoietic stem cell transplants (a-HSCT). MDR colonization is highly prevalent among a-HSCT patients, due to drug-induced intestinal dysbiosis. Primary outcome of the study was to assess the epidemiology and risk factors for BSIs in the 1st year after a-HSCT. Secondary endpoints were to examine the prevalence of MDR bacterial colonization and factors affecting 1-year post-transplant overall survival (OS).
In this single-center observational cohort study, all consecutive adult patients undergoing a-HSCT for hematological malignancies between 2012 and 2021 were retrospectively enrolled at the Stem Cell Transplant Center, AOU Città della Salute e della Scienza, Turin (Italy). Cumulative Incidence and risk factors for BSIs were analyzed by Gray and Fine-Gray tests, respectively. OS was evaluated with Kaplan-Meier, while the influence of covariates on OS with Cox regression analysis.
Two hundred and seventy nine patients were enrolled in the study, 43% of which developed BSI within the 1st-year post-transplant. The median onset of BSIs was 10 days after a-HSCT and Gram-negative bacteria were the most common causative agents (58.3%). 20.8% of patients had a positive rectal swab (RS) for MDR bacteria, with extended-spectrum β-lactamases (ESBLs)-producing being the most common colonizers (60.3% of positive RS), followed by carbapenem-resistant Enterobacteriaceae (CRE) (29.3%). Multivariate competing risks regression analysis showed that colonization by MDR bacteria was associated with a higher incidence of BSIs (SDHR 1.49, 95%CI 1.01-2.20), along with the type of underlying disease (SDHR 0.73, 95%CI 0.58-0.91), donor type (SDHR 1.62, 95%CI 1.02-2.58) and an advanced disease status at the time of transplantation (SDHR 1.57, 95%CI 1.05-2.35). One-year mortality rate was 25.4%. RS colonization was not associated with increased mortality; while BSIs adversely affected OS (SDHR 1.52, 95%CI 1.02-2.26).
BSIs are common complications in a-HSCT, with evidence suggesting a negative impact on OS. Although MDR colonization is not independently linked to increased mortality in a-HSCT, it appears to be associated with an elevated risk of subsequent BSI development. These findings underscore the potential value of pre-transplant surveillance, contact precautions, and early targeted antimicrobial therapy in colonized patients to help mitigate infection-related morbidity and mortality.
血流感染（BSIs）对接受异基因造血干细胞移植（a-HSCT）的患者构成严重威胁。由于药物引起的肠道菌群失调，多重耐药菌定植在a-HSCT患者中非常普遍。该研究的主要结果是评估a-HSCT后第1年BSIs的流行病学和危险因素。次要终点是检查多重耐药菌定植的患病率以及影响移植后1年总生存率（OS）的因素。
在这项单中心观察性队列研究中，2012年至2021年间在意大利都灵市健康与科学大学医院干细胞移植中心接受a-HSCT治疗血液系统恶性肿瘤的所有连续成年患者被纳入研究。分别通过Gray检验和Fine-Gray检验分析BSIs的累积发病率和危险因素。采用Kaplan-Meier法评估OS，同时通过Cox回归分析协变量对OS的影响。
279名患者纳入研究，其中43%在移植后第1年内发生BSI。BSIs的中位发病时间为a-HSCT后10天，革兰氏阴性菌是最常见的病原体（58.3%）。20.8%的患者直肠拭子（RS）检测出多重耐药菌呈阳性，产超广谱β-内酰胺酶（ESBLs）的细菌是最常见的定植菌（阳性RS的60.3%），其次是耐碳青霉烯类肠杆菌科细菌（CRE）（29.3%）。多因素竞争风险回归分析显示，多重耐药菌定植与BSIs的发生率较高相关（标准化危险比1.49，95%置信区间1.01-2.20），同时还与基础疾病类型（标准化危险比0.73，95%置信区间0.58-0.91）、供体类型（标准化危险比1.62，95%置信区间1.02-2.58）以及移植时的疾病晚期状态（标准化危险比1.57，95%置信区间1.05-2.35）有关。1年死亡率为25.4%。RS定植与死亡率增加无关；而BSIs对OS有不利影响（标准化危险比1.52，95%置信区间1.02-2.26）。
BSIs是a-HSCT中常见的并发症，并对OS有负面影响。虽然多重耐药菌定植与a-HSCT患者死亡率增加无独立关联，但似乎与随后发生BSI的风险升高有关。这些发现强调了移植前监测、接触预防措施以及对定植患者进行早期靶向抗菌治疗的潜在价值，以帮助降低感染相关的发病率和死亡率。
