METHODS: Swabs were taken from 62 sinks within two newly opened wards at Great Ormond Street Hospital, samples were taken before and after the wards opened to understand the impact of patient occupancy on sink micro-organisms. Culturable bacteria were identified by MALDI-TOF and virulence factors assessed through phenotypic methods.
RESULTS: A total of 106 bacterial isolates were recovered including 24 Pseudomonas isolates. Of these 25% were identified as P. oleovorans, 21% P. aeruginosa, 17% P. composti, 13% P. alicalipha, 8% P. monteilii, 4% P. putida, 4% P. stutzeri and 8% could only be identified to genus level by MALDI-TOF. Differences were seen in both the number of Pseudomonas isolates and virulence production between the two wards, overall 25% of the Pseudomonas isolates produced pigment, 58% were capable of haemolysis, 87.5% were able to swim, 83.3% were capable of twitching motility, 33.3% produced alkaline protease and 8.3% produced gelatinase.
CONCLUSIONS: Results suggest that patients may be back-contaminating sinks with colonizing organisms which has ongoing implications for infection prevention and control. Additionally, this work highlights the ability of non-aeruginosa Pseudomonas to produce virulence factors traditionally associated with P. aeruginosa.
方法:棉签取自大奥蒙德街医院两个新开的病房内的62个水槽,在病房开放之前和之后采集样本,以了解患者入住对水槽微生物的影响。通过MALDI-TOF鉴定可培养细菌,并通过表型方法评估毒力因子。
结果:共回收细菌分离株106株,其中假单胞菌分离株24株。在这25%的人中,他们被确定为P.oleovorans,21%铜绿假单胞菌,17%。13%阿利卡氏菌,8%蒙氏疟原虫,4%P.putida,4%牛肝菌,8%只能通过MALDI-TOF鉴定为属水平。两个病区之间的假单胞菌分离株数量和毒力产生均存在差异,总体上25%的假单胞菌分离物产生色素,58%的人能够溶血,87.5%会游泳,83.3%的人能够抽搐运动,33.3%产生碱性蛋白酶,和8.3%产生的明胶酶。
结论:结果表明,患者可能是由定植生物污染的水槽,这对感染的预防和控制具有持续的意义。此外,这项工作强调了非铜绿假单胞菌产生传统上与铜绿假单胞菌相关的毒力因子的能力。