Blanc D S, Gomes Magalhaes B, Abdelbary M, Prod'hom G, Greub G, Wasserfallen J B, Genoud P, Zanetti G, Senn L
Service of Hospital Preventive Medicine, Lausanne University Hospital, Lausanne, Switzerland; Nurse Directorate, Lausanne University Hospital, Lausanne, Switzerland.
Service of Hospital Preventive Medicine, Lausanne University Hospital, Lausanne, Switzerland.
J Hosp Infect. 2016 May;93(1):63-7. doi: 10.1016/j.jhin.2016.02.010. Epub 2016 Mar 3.
During an environmental investigation of Pseudomonas aeruginosa in intensive care units, the liquid hand soap was found to be highly contaminated (up to 8 × 10(5)cfu/g) with this pathogen. It had been used over the previous five months and was probably contaminated during manufacturing.
To evaluate the burden of this contamination on patients by conducting an epidemiological investigation using molecular typing combined with whole genome sequencing (WGS).
P. aeruginosa isolates from clinical specimens were analysed by double locus sequence typing (DLST) and compared with isolates recovered from the soap. Medical charts of patients infected with a genotype identical to those found in the soap were reviewed. WGS was performed on soap and patient isolates sharing the same genotype.
P. aeruginosa isolates (N = 776) were available in 358/382 patients (93.7%). Only three patients (0.8%) were infected with a genotype found in the soap. Epidemiological investigations showed that the first patient was not exposed to the soap, the second could have been exposed, and the third was indeed exposed. WGS showed a high number of core single nucleotide polymorphism differences between patients and soap isolates. No close genetic association was observed between soap and patient isolates, ruling out the hypothesis of transmission.
Despite a highly contaminated soap, the combined investigation with DLST and WGS ruled out any impact on patients. Hand hygiene performed with alcohol-based solution for >15 years was probably the main reason. However, such contamination represents a putative reservoir of pathogens that should be avoided in the hospital setting.
在对重症监护病房的铜绿假单胞菌进行环境调查时，发现液体洗手液被这种病原体高度污染（高达8×10⁵cfu/g）。该洗手液在过去五个月中一直在使用，很可能在生产过程中被污染。
通过结合分子分型和全基因组测序（WGS）进行流行病学调查，评估这种污染对患者的影响。
对临床标本中的铜绿假单胞菌分离株进行双位点序列分型（DLST）分析，并与从肥皂中分离出的菌株进行比较。对感染了与肥皂中发现的基因型相同的患者的病历进行了审查。对具有相同基因型的肥皂和患者分离株进行了WGS。
358/382例患者（93.7%）有铜绿假单胞菌分离株（N = 776）。只有三名患者（0.8%）感染了肥皂中发现的基因型。流行病学调查显示，第一名患者未接触该肥皂，第二名患者可能接触过，第三名患者确实接触过。WGS显示患者和肥皂分离株之间存在大量核心单核苷酸多态性差异。在肥皂和患者分离株之间未观察到密切的遗传关联，排除了传播的假设。
尽管肥皂受到高度污染，但DLST和WGS的联合调查排除了对患者的任何影响。使用含酒精溶液进行手部卫生清洁超过15年可能是主要原因。然而，这种污染代表了医院环境中应避免的病原体潜在储存库。
