Szczepura Ala, Manzoor Susan, Hardy Katherine, Stallard Nigel, Parsons Helen, Gossain Savita, Hawkey Peter M
Warwick Medical School, University of Warwick, Coventry, UK.
BMC Infect Dis. 2014 Mar 21;14:154. doi: 10.1186/1471-2334-14-154.
Despite scientific advances in typing of C. difficile strains very little is known about how hospital staff use typing results during periods of increased incidence (PIIs). This qualitative study, undertaken alongside a randomised controlled trial (RCT), explored this issue. The trial compared ribotyping versus more rapid genotyping (MLVA or multilocus variable repeat analysis) and found no significant difference in post 48 hour cases (C difficile transmissions).
In-depth qualitative interviews with senior staff in 11/16 hospital trusts in the trial (5 MLVA and 6 Ribotyping). Semi-structured interviews were conducted at end of the trial period. Transcripts were content analysed using framework analysis supported by NVivo-8 software. Common sub-themes were extracted by two researchers independently. These were compared and organised into over-arching categories or 'super-ordinate themes'.
The trial recorded that 45% of typing tests had some impact on infection control (IC) activities. Interviews indicated that tests had little impact on initial IC decisions. These were driven by hospital protocols and automatically triggered when a PII was identified. To influence decision-making, a laboratory turnaround time < 3 days (ideally 24 hours) was suggested; MLVA turnaround time was 5.3 days. Typing results were predominantly used to modify initiated IC activities such as ward cleaning, audits of practice or staff training; major decisions (e.g. ward closure) were unaffected. Organisational factors could limit utilisation of MLVA results. Results were twice as likely to be reported as 'aiding management' (indirect benefit) than impacting on IC activities (direct effect). Some interviewees considered test results provided reassurance about earlier IC decisions; others identified secondary benefits on organisational culture. An underlying benefit of improved discrimination provided by MLVA typing was the ability to explore epidemiology associated with CDI cases in a hospital more thoroughly.
Ribotyping and MLVA are both valued by users. MLVA had little additional direct impact on initial infection control decisions. This would require reduced turnaround time. The major impact is adjustments to earlier IC measures and retrospective reassurance. For this, turnaround time is less important than discriminatory power. The potential remains for wider use of genotyping to examine transmission routes.
尽管艰难梭菌菌株分型在科学上取得了进展，但对于医院工作人员在发病率上升期间（PIIs）如何使用分型结果却知之甚少。这项定性研究是在一项随机对照试验（RCT）的同时进行的，旨在探讨这个问题。该试验比较了核糖体分型与更快速的基因分型（MLVA或多位点可变重复分析），发现在48小时后的病例（艰难梭菌传播）方面没有显著差异。
对试验中16个医院信托机构中的11个机构的高级工作人员进行深入的定性访谈（5个采用MLVA，6个采用核糖体分型）。在试验期结束时进行半结构化访谈。使用NVivo - 8软件支持的框架分析对访谈记录进行内容分析。两位研究人员独立提取共同的子主题。对这些子主题进行比较并组织成总体类别或“上位主题”。
试验记录显示，45%的分型检测对感染控制（IC）活动有一定影响。访谈表明，检测对初始IC决策影响不大。这些决策由医院规程驱动，在确定PII时自动触发。为了影响决策，建议实验室周转时间<3天（理想情况下为24小时）；MLVA的周转时间为5.3天。分型结果主要用于修改已启动的IC活动，如病房清洁、实践审核或员工培训；重大决策（如病房关闭）不受影响。组织因素可能会限制MLVA结果的利用。结果被报告为“有助于管理”（间接益处）的可能性是影响IC活动（直接效果）的两倍。一些受访者认为检测结果为早期IC决策提供了保证；其他人则指出对组织文化有次要益处。MLVA分型提供的更好的鉴别能力所带来的潜在好处是能够更彻底地探索医院中与CDI病例相关的流行病学。
核糖体分型和MLVA都受到用户重视。MLVA对初始感染控制决策几乎没有额外的直接影响。这需要缩短周转时间。主要影响是对早期IC措施的调整和回顾性保证。为此，周转时间不如鉴别能力重要。基因分型在更广泛地用于检查传播途径方面仍有潜力。
