Infection Control Section, Toho University Omori Medical Center, Tokyo, Japan.
Department of General Medicine and Emergency Care, Toho University School of Medicine, Tokyo, Japan.
BMC Infect Dis. 2024 Sep 17;24(1):989. doi: 10.1186/s12879-024-09841-9.
The nosocomial transmission of toxin-producing Clostridioides difficile is a significant concern in infection control. C. difficile, which resides in human intestines, poses a risk of transmission, especially when patients are in close contact with medical staff.
To investigate the nosocomial transmission of C. difficile in a single center, we analyzed the genetic relationships of the bacteria. This was done using draft whole-genome sequencing (WGS) and examining single nucleotide polymorphisms (SNPs) in core-genome, alongside data regarding the patient's hospital wards and room changes. Our retrospective analysis covered 38 strains, each isolated from a different patient, between April 2014 and January 2015.
We identified 38 strains that were divided into 11 sequence types (STs). ST81 was the most prevalent (n = 11), followed by ST183 (n = 10) and ST17 (n = 7). A cluster of strains that indicated suspected nosocomial transmission (SNT) was identified through SNP analysis. The draft WGS identified five clusters, with 16 of 38 strains belonging to these clusters. There were two clusters for ST81 (ST81-SNT-1 and ST81-SNT-2), two for ST183 (ST183-SNT-1 and ST183-SNT-2), and one for ST17 (ST17-SNT-1). ST183-SNT-1 was the largest SNT cluster, encompassing five patients who were associated with Wards A, B, and K. The most frequent room changer was a patient labeled Pt08, who changed rooms seven times in Ward B. Patients Pt36 and Pt10, who were also in Ward B, had multiple admissions and discharges during the study period.
Additional culture tests and SNP analysis of C. difficile using draft WGS revealed silent transmission within the wards, particularly in cases involving frequent room changes and repeated admissions and discharges. Monitoring C. difficile transmission using WGS-based analysis could serve as a valuable marker in infection control management.
产毒艰难梭菌（Clostridioides difficile）的医院内传播是感染控制中的一个重大问题。艰难梭菌存在于人类肠道中，具有传播风险，尤其是当患者与医务人员密切接触时。
为了调查单一中心的艰难梭菌医院内传播情况，我们分析了细菌的遗传关系。这是通过使用草案全基因组测序（WGS）和检测核心基因组中的单核苷酸多态性（SNP）以及有关患者病房和房间变化的数据来完成的。我们的回顾性分析涵盖了 2014 年 4 月至 2015 年 1 月期间从 38 位不同患者中分离出的 38 株细菌。
我们鉴定出 38 株分为 11 种序列类型（ST）的细菌。ST81 最为常见（n = 11），其次是 ST183（n = 10）和 ST17（n = 7）。通过 SNP 分析，我们发现了一个疑似医院内传播（SNT）的菌株簇。草案 WGS 鉴定出了五个聚类，其中 38 株中的 16 株属于这些聚类。有两个 ST81 聚类（ST81-SNT-1 和 ST81-SNT-2），两个 ST183 聚类（ST183-SNT-1 和 ST183-SNT-2），一个 ST17 聚类（ST17-SNT-1）。ST183-SNT-1 是最大的 SNT 聚类，包括与病房 A、B 和 K 相关的五名患者。最频繁的换房者是患者 Pt08，他在病房 B 换了七次房。在研究期间，同样在病房 B 的患者 Pt36 和 Pt10 多次入院和出院。
使用草案 WGS 对艰难梭菌进行额外的培养试验和 SNP 分析揭示了病房内的隐性传播，特别是在频繁换房、多次入院和出院的情况下。使用 WGS 分析监测艰难梭菌传播可以作为感染控制管理的有价值的标志物。
