Division of Gastroenterology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA.
Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA.
Clin Infect Dis. 2021 Mar 1;72(5):806-813. doi: 10.1093/cid/ciaa159.
Current approaches in tracking Clostridioides difficile infection (CDI) and individualizing patient management are incompletely defined.
We recruited 468 subjects with CDI at Mayo Clinic Rochester between May and December 2016 and performed whole-genome sequencing (WGS) on C. difficile isolates from 397. WGS was also performed on isolates from a subset of the subjects at the time of a recurrence of infection. The sequence data were analyzed by determining core genome multilocus sequence type (cgMLST), with isolates grouped by allelic differences and the predicted ribotype.
There were no correlations between C. difficile isolates based either on cgMLST or ribotype groupings and CDI outcome. An epidemiologic assessment of hospitalized subjects harboring C. difficile isolates with ≤2 allelic differences, based on standard infection prevention and control assessment, revealed no evidence of person-to-person transmission. Interestingly, community-acquired CDI subjects in 40% of groups with ≤2 allelic differences resided within the same zip code. Among 18 subjects clinically classified as having recurrent CDI, WGS revealed 14 with initial and subsequent isolates differing by ≤2 allelic differences, suggesting a relapse of infection with the same initial strain, and 4 with isolates differing by >50 allelic differences, suggesting reinfection. Among the 5 subjects classified as having a reinfection based on the timing of recurrence, 3 had isolates with ≤2 allelic differences between them, suggesting a relapse, and 2 had isolates differing by >50 allelic differences, suggesting reinfection.
Our findings point to potential transmission of C. difficile in the community. WGS better differentiates relapse from reinfection than do definitions based on the timing of recurrence.
目前在追踪艰难梭菌感染（CDI）和个体化患者管理方面的方法并不完善。
我们在 2016 年 5 月至 12 月期间招募了在梅奥诊所罗切斯特分校就诊的 468 名 CDI 患者，并对 397 名患者的艰难梭菌分离株进行了全基因组测序（WGS）。在感染复发时，我们还对部分患者的分离株进行了 WGS。通过确定核心基因组多位点序列类型（cgMLST）对序列数据进行分析，根据等位基因差异和预测的核糖体分型对分离株进行分组。
无论是基于 cgMLST 还是核糖体分型分组，CDI 结果与艰难梭菌分离株均无相关性。对住院患者进行的基于标准感染预防和控制评估的携带≤2 个等位基因差异的艰难梭菌分离株的流行病学评估显示，人与人之间没有传播的证据。有趣的是，在≤2 个等位基因差异的 40%的组中，40%的社区获得性 CDI 患者居住在同一个邮政编码区域内。在 18 名临床上被归类为患有复发性 CDI 的患者中，WGS 显示 14 名患者的初始和后续分离株差异≤2 个等位基因差异，提示感染同一初始菌株的复发，而 4 名患者的分离株差异>50 个等位基因差异，提示再感染。在基于复发时间分类的 5 名再感染患者中，有 3 名患者的分离株之间差异≤2 个等位基因差异，提示复发，2 名患者的分离株差异>50 个等位基因差异，提示再感染。
我们的研究结果表明艰难梭菌在社区中可能存在传播。WGS 比基于复发时间的定义更能区分复发和再感染。
