Webster C A, Towner K J
Department of Microbiology & PHLS Laboratory, University Hospital, Queen's Medical Centre, Nottingham, NG7 2UH.
J Hosp Infect. 2000 Apr;44(4):254-60. doi: 10.1053/jhin.1999.0703.
Bacterial cross-transmission was investigated during a 12-month period in an adult intensive care unit (ICU) by the generation of random amplified polymorphic DNA (RAPD) fingerprinting profiles, combined with automated laser fluorescence (ALF) analysis. The potential episodes of cross-transmission identified, were compared with those detected by the conventional first-line screen of antibiogram typing. Over the year, 215 primary gram-negative bacterial isolates were obtained from 160 patients. In total, 22 possible episodes of cross-transmission, involving 70 (44%) of the 160 patients, were identified by RAPD-ALF analysis, and 19 of these were substantiated with epidemiological evidence. Conversely, 31 possible episodes were identified on the basis of antibiogram data, but only three of these episodes, two involving Acinetobacter baumannii and one involving Serratia marcescens, correlated with those identified by RAPD-ALF analysis. It was concluded that analysis of antibiogram data alone is an unreliable method for assessing bacterial cross-transmission, unless the organism involved has a particularly stable or unusual resistance pattern. In contrast, the technique of RAPD-ALF analysis may provide a rapid and simple technique for obtaining an insight into the population dynamics of gram-negative bacteria in adult ICUs.
通过随机扩增多态性DNA（RAPD）指纹图谱分析并结合自动激光荧光（ALF）分析，在一家成人重症监护病房（ICU）对细菌交叉传播情况进行了为期12个月的调查。将通过RAPD-ALF分析确定的潜在交叉传播事件与通过传统一线抗生素敏感性试验分型筛查检测到的事件进行比较。在这一年中，从160名患者中分离出215株原发性革兰氏阴性菌。通过RAPD-ALF分析共确定了22起可能的交叉传播事件，涉及160名患者中的70名（44%），其中19起有流行病学证据支持。相反，根据抗生素敏感性试验数据确定了31起可能的事件，但其中只有3起事件，两起涉及鲍曼不动杆菌，一起涉及粘质沙雷氏菌，与通过RAPD-ALF分析确定的事件相关。得出的结论是，除非所涉及的细菌具有特别稳定或不寻常的耐药模式，否则仅分析抗生素敏感性试验数据是评估细菌交叉传播的不可靠方法。相比之下，RAPD-ALF分析技术可能为深入了解成人ICU中革兰氏阴性菌的种群动态提供一种快速简便的技术。
