Gallardo-Pizarro Antonio, Lopera Carlos, Peyrony Olivier, Monzo-Gallo Patricia, Aiello Tommaso Francesco, Martinez-Urrea Ana, Herrera Sabina, Del Río Ana, Teijon-Lumbreras Christian, Chumbita Mariana, Jimenez-Vicente Carlos, Cortés Albert, Bodro Marta, Pitart Cristina, Rubio Elisa, Mensa Josep, Soriano Alex, Martínez Jose Antonio, Garcia-Vidal Carolina
Infectious Disease Department, Hospital Clinic of Barcelona-Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain; Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.
Infectious Disease Department, Hospital Clinic of Barcelona-Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain.
Clin Microbiol Infect. 2025 Jun 5. doi: 10.1016/j.cmi.2025.05.033.
This study assessed the prevalence of multidrug-resistant Gram-negative bacilli (MDR-GNB) colonization in rectal swabs from haematological patients with malignancies undergoing routine surveillance and explored the relationship between MDR-GNB colonization and subsequent development of bloodstream infections (BSIs).
Between January 2020 and September 2022, all patients admitted to our haematology ward underwent weekly MDR-GNB colonization screening via rectal swabs. A retrospective analysis was performed. MDR-GNB were defined per 2022 European Society of Clinical Microbiology and Infectious Diseases criteria: (a) third-generation cephalosporin-resistant Enterobacterales (3GCephRE), (b) carbapenem-resistant Enterobacterales (CRE), (c) Pseudomonas aeruginosa with difficult-to-treat resistance (DTR), and (d) carbapenem-resistant Acinetobacter baumannii.
Among 3024 rectal swabs from 699 patients, 503 of 3024 (16.6%) tested positive for MDR-GNB in 192 of 699 patients (27.5%). The most prevalent organisms were Escherichia coli (248/503; 49.3%), Klebsiella pneumoniae complex (125/503; 24.9%), and P. aeruginosa (36/503; 7.2%). A total of 59 of 503 (11.7%) colonizations of CRE were identified. Overall, 27 of 192 (14.1%) patients were colonized at admission, primarily by 3GCephRE (27/29; 93.1%). Colonization with CRE and DTR P. aeruginosa was more frequently documented after several days of hospitalization. BSI occurred in 74 of 192 (38.5%) colonized and 61 of 507 (12.0%) non-colonized patients. MDR-GNB caused 57 of 166 BSIs episodes, 50 of 57 (87.7%) of which were in colonized patients. The unadjusted concordance rate between rectal swab isolates and blood cultures was observed in 43 of 90 BSIs (47.8%) occurring in colonized patients, with a positive predictive value (PPV) of 36.4% and a negative predictive value (NPV) of 99.9% for DTR P. aeruginosa; a PPV of 25.0% and an NPV of 99.9% for CRE; and a PPV of 14.6% and an NPV of 99.0% for 3GCephRE.
Routine weekly surveillance for MDR-GNB in haematological patients enables early identification of colonization, often preceding MDR-GNB BSIs. Further studies using adjusted analyses are needed to establish its independent predictive value.
本研究评估了接受常规监测的血液系统恶性肿瘤患者直肠拭子中多重耐药革兰阴性杆菌（MDR - GNB）定植的发生率，并探讨了MDR - GNB定植与随后发生血流感染（BSI）之间的关系。
在2020年1月至2022年9月期间，我们血液科病房的所有患者每周通过直肠拭子进行MDR - GNB定植筛查。进行了回顾性分析。MDR - GNB根据2022年欧洲临床微生物学和传染病学会标准定义：（a）对第三代头孢菌素耐药的肠杆菌科细菌（3GCephRE），（b）对碳青霉烯类耐药的肠杆菌科细菌（CRE），（c）具有难治性耐药的铜绿假单胞菌（DTR），以及（d）对碳青霉烯类耐药的鲍曼不动杆菌。
在来自699例患者的3024份直肠拭子中，3024份中的503份（16.6%）在699例患者中的192例（27.5%）检测为MDR - GNB阳性。最常见的菌株是大肠埃希菌（248/503；49.3%）、肺炎克雷伯菌复合体（125/503；24.9%）和铜绿假单胞菌（36/503；7.2%）。共鉴定出503例定植中的59例（11.7%）为CRE。总体而言，192例患者中的27例（14.1%）在入院时即有定植，主要为3GCephRE（27/29；93.1%）。住院几天后，CRE和DTR铜绿假单胞菌的定植记录更为频繁。192例定植患者中有74例（38.5%）发生了BSI，507例未定植患者中有61例（12.0%）发生了BSI。MDR - GNB导致了166例BSI事件中的57例，其中57例中的50例（87.7%）发生在定植患者中。在定植患者发生的90例BSI中的43例（47.8%）观察到直肠拭子分离株与血培养之间未经调整的一致性率，对于DTR铜绿假单胞菌，阳性预测值（PPV）为36.4%，阴性预测值（NPV）为99.9%；对于CRE，PPV为25.0%，NPV为99.9%；对于3GCephRE，PPV为14.6%，NPV为99.0%。
对血液系统患者进行每周一次的MDR - GNB常规监测能够早期识别定植情况，通常在MDR - GNB引起的BSI之前。需要使用调整分析进行进一步研究以确定其独立预测价值。
