1Medical Intensive Care Unit, CHU Bordeaux, Pellegrin universitary hospital, Place Amélie Raba-Léon, F-33000 Bordeaux, France.
2UMR 5234 CNRS, Bordeaux University, F-33000 Bordeaux, France.
Antimicrob Resist Infect Control. 2019 Jul 10;8:112. doi: 10.1186/s13756-019-0572-9. eCollection 2019.
Extended-spectrum beta-lactamases-producing (ESBL-E) are disseminating worldwide especially in Intensive Care Units (ICUs) and are responsible for increased health costs and mortality. The aims of this work were to study ESBL-E dissemination in ICU and to assess the impact of ESBL-E fecal carriage on subsequent infections during a non-outbreak situation.
We therefore screened every patient at admission then once a week in a medical ICU between January and June 2015. Each ESBL-E isolate was characterized by ESBL genes PCR amplification and the clonal dissemination was assessed by Pulsed-Field Gel Electrophoresis (PFGE).
Among the 608 screened patients, 55 (9%) were colonized by ESBL-E. Forty-four isolates were available for further analysis. Most of them (43/44, 98%) contained a ESBL gene from the CTX-M group. Only one case of ESBL-E cross-transmission occurred, even for acquired ESBL-E colonization. Subsequent infection by ESBL-E occurred in 6/55 (11%) patients and infecting ESBL-E strains were the colonizing ones. ESBL-E faecal carriage had a negative predictive value of 100% and a positive predictive value of 40% to predict ESBL-E ventilator associated-pneumonia (VAP). Alternatives to carbapenems consisting in piperacillin-tazobactam, ceftolozane-tazobactam and ceftazidime-avibactam were all active on this panel of ESBL-E.
ESBL-E expansion and acquisition in ICU in a non-outbreak situation are not any more fully explained by cross-transmission. Mechanisms underlying ESBL-E dissemination in ICU are still to investigate. Interestingly, as far as we know, our study demonstrates for the first time by PFGE that the colonizing strain is indeed the infecting one in case of subsequent ESBL-E infection. Nevertheless, subsequent ESBL-E infection remains a rare event conferring poor positive predictive value for ESBL-E colonization to predict ESBL-E VAP. Relevance of systematic ESBL-E faecal screening at ICU admission and during ICU stay needs further investigation.
产超广谱β-内酰胺酶（ESBL-E）在全球范围内传播，特别是在重症监护病房（ICU），导致医疗费用增加和死亡率上升。本研究的目的是研究 ICU 中 ESBL-E 的传播，并评估非暴发情况下 ESBL-E 粪便携带对随后感染的影响。
因此，我们在 2015 年 1 月至 6 月期间对 ICU 中的每位入院患者进行筛查，然后每周筛查一次。通过 PCR 扩增 ESBL 基因对每个 ESBL-E 分离株进行特征分析，通过脉冲场凝胶电泳（PFGE）评估克隆传播。
在 608 名筛查患者中，55 名（9%）患者定植 ESBL-E。44 株分离株可用于进一步分析。其中大多数（43/44，98%）含有 CTX-M 组的 ESBL 基因。仅发生 1 例 ESBL-E 交叉传播，即使是获得性 ESBL-E 定植。55 名患者中有 6 名（11%）发生 ESBL-E 后继感染，感染的 ESBL-E 菌株为定植菌株。ESBL-E 粪便携带对预测 ESBL-E 呼吸机相关性肺炎（VAP）的阴性预测值为 100%，阳性预测值为 40%。哌拉西林他唑巴坦、头孢洛扎他唑巴坦和头孢他啶-阿维巴坦等替代碳青霉烯类药物对这组 ESBL-E 均有效。
在非暴发情况下，ICU 中 ESBL-E 的扩展和获得不再完全由交叉传播解释。ESBL-E 在 ICU 中传播的机制仍有待研究。有趣的是，据我们所知，本研究首次通过 PFGE 证明，在发生后继 ESBL-E 感染的情况下，定植株确实是感染株。然而，后继 ESBL-E 感染仍然是一个罕见事件，对预测 ESBL-E 定植预测 ESBL-E VAP 的阳性预测值较差。需要进一步研究在 ICU 入院和住院期间系统进行 ESBL-E 粪便筛查的相关性。
