Markowitz S M, Smith S M, Williams D S
J Infect Dis. 1983 Jul;148(1):18-23. doi: 10.1093/infdis/148.1.18.
To evaluate the usefulness of plasmid pattern analysis as an epidemiologic tool and to determine the mechanism of resistance to silver sulfadiazine and mafenide acetate, silver sulfadiazine-resistant, mafenide acetate-resistant Enterobacter cloacae isolates from a 1976 outbreak of infections in a burn unit (group I) were analyzed retrospectively. These strains were compared with various E cloacae isolates (groups II-V), including E cloacae isolates from a more recent (1982) burn unit outbreak (group V). Agarose gel electrophoresis (AGE) of DNA isolated from "epidemic" strains of E cloacae revealed a uniform pattern of four plasmid DNA bands, ranging in molecular size from 66 to 2 megadaltons. No such plasmid pattern was seen in silver sulfadiazine-, mafenide acetate-susceptible isolates of E cloacae in groups II, III, and V. Analysis of non-E cloacae coisolates suggested that silver sulfadiazine resistance was associated with the 55-megadalton plasmid. Plasmid pattern analysis easily separated "epidemic" E cloacae isolated in 1976 from those isolated in 1982.
为评估质粒图谱分析作为一种流行病学工具的实用性，并确定对磺胺嘧啶银和醋酸磺胺米隆耐药的机制，对1976年烧伤病房感染暴发中分离出的耐磺胺嘧啶银、耐醋酸磺胺米隆的阴沟肠杆菌菌株（第一组）进行了回顾性分析。将这些菌株与各种阴沟肠杆菌分离株（第二至五组）进行比较，包括来自最近（1982年）烧伤病房暴发的阴沟肠杆菌分离株（第五组）。从阴沟肠杆菌“流行”菌株中分离的DNA的琼脂糖凝胶电泳（AGE）显示出四条质粒DNA条带的一致图谱，分子大小在66至2兆道尔顿之间。在第二、三、五组中对磺胺嘧啶银、醋酸磺胺米隆敏感的阴沟肠杆菌分离株中未观察到这种质粒图谱。对非阴沟肠杆菌共分离株的分析表明，磺胺嘧啶银耐药性与55兆道尔顿的质粒有关。质粒图谱分析很容易将1976年分离的“流行”阴沟肠杆菌与1982年分离的阴沟肠杆菌区分开来。
