Carolinas Medical Center, Atrium Health, Charlotte, North Carolina, USA.
Microbiol Spectr. 2022 Jun 29;10(3):e0175321. doi: 10.1128/spectrum.01753-21. Epub 2022 Jun 21.
Venous catheter-related bloodstream infections represent a significant problem in the United States. Our objective was to determine daily changes in skin microbiome profiles up to 72h postchlorhexidine treatment. Left and right forearm skin swab samples were obtained from 10 healthy volunteers over 72h at 24h intervals. Dorsal surface of left arm was treated with chlorohexidine gluconate (CHG) at initial time point (T = 0), while the right arm remained untreated (control). Swab samples were obtained shortly before (T = 0) and after CHG treatment (T = 24-48-72h). Bacterial DNA extraction, 16S rRNA gene V1-V3 sequencing and taxonomic annotation were performed using ZymoBIOMICS pipeline. PERMANOVA, linear discriminant and bacterial interaction network analyses were performed. A total of 13 total phyla, 273 genera, and 950 total species were detected across all time points, CHG-treated or CHG-untreated. Most abundant species included Cutibacterium acnes, Staphylococcus epidermidis, and Rothia Mucilaginosa. Low biomass-related inconsistent taxa detection was observed. PERMANOVA suggested a marginal difference between CHG-treated and CHG-untreated microbiome profiles (Genera: P(perm) = 0.0531; Species: P(perm) = 0.0450). Bacterial interaction network guided PERMANOVA analyses detected a microbiome change over time, suggesting a consistent CHG treatment-specific change. LEfSe identified Finegoldia magna, Bacillus pumilus, Bacillus thermoamylovorans as the only distinctive species. These species were more abundant and/or present post-CHG treatment in the CHG-treated group. These findings suggest that the skin microbiome was not significantly different 24, 48, or 72h after CHG treatment. Previous culture-based studies have found similar results after 24h. Future studies will be needed to determine the mechanisms of bacterial regrowth after CHG treatment. Annually, over 80,000 central line infections occur in the United States. Understanding the pathogenesis of these infections is crucial. Chlorhexidine is the most commonly used skin preparation before line placement. We hypothesized that the use of chlorhexidine and dressings will alter the normal arm skin microbiome over a period of 72h. We used 16S-rRNA gene next generation sequencing (NGS) to determine the forearm skin microbiome of volunteers. The left arm was swabbed with chlorhexidine and the right arm served as control. The skin microbiome returned to normal after 24h. Our NGS results confirm findings of two previous culture-based studies. Relative abundance of spp. in the chlorhexidine-treated samples was increased, consistent with one previous study. Based on the results of this pilot study, we will need to measure viable bacteria during a 24h time course following chlorhexidine treatment to understand the source of skin microbiome replenishment.
静脉导管相关血流感染是美国的一个严重问题。我们的目的是确定氯己定处理后 72 小时内皮肤微生物组谱的每日变化。在 72 小时内每隔 24 小时从 10 名健康志愿者的左右前臂采集皮肤拭子样本。在初始时间点（T=0）用葡萄糖酸氯己定（CHG）处理左手臂的背侧表面，而右臂未处理（对照）。在 CHG 处理前（T=0）和处理后（T=24-48-72h）立即采集拭子样本。使用 ZymoBIOMICS 管道进行细菌 DNA 提取、16S rRNA 基因 V1-V3 测序和分类注释。进行 PERMANOVA、线性判别和细菌相互作用网络分析。在所有时间点，CHG 处理或未处理的情况下，共检测到 13 个总门、273 个属和 950 个总种。最丰富的物种包括痤疮丙酸杆菌、表皮葡萄球菌和罗特氏菌。观察到低生物量相关的不一致分类群检测。PERMANOVA 表明 CHG 处理和未处理的微生物组谱之间存在边缘差异（属：P(perm)=0.0531；种：P(perm)=0.0450）。细菌相互作用网络引导的 PERMANOVA 分析检测到随时间的微生物组变化，表明存在一致的 CHG 处理特异性变化。LEfSe 确定了嗜金黄微球菌、短小芽孢杆菌和解淀粉芽孢杆菌为唯一独特的物种。这些物种在 CHG 处理组中更丰富和/或在 CHG 处理后存在。这些发现表明，CHG 处理后 24、48 或 72 小时皮肤微生物组没有明显差异。以前的基于培养的研究在 24 小时后发现了类似的结果。未来的研究将需要确定 CHG 处理后细菌再生长的机制。每年，美国有超过 80,000 例中心导管感染。了解这些感染的发病机制至关重要。氯己定是放置导管前最常用的皮肤准备药物。我们假设氯己定和敷料的使用会在 72 小时内改变正常手臂皮肤的微生物组。我们使用 16S-rRNA 基因下一代测序（NGS）来确定志愿者的前臂皮肤微生物组。左臂用氯己定擦拭，右臂作为对照。24 小时后，皮肤微生物组恢复正常。我们的 NGS 结果证实了两项先前基于培养的研究的发现。在氯己定处理样本中， 属的相对丰度增加，与一项先前的研究一致。基于这项初步研究的结果，我们将需要在 CHG 处理后 24 小时的时间过程中测量活菌，以了解皮肤微生物组补充的来源。
