Nagy E, Koczián Z, Prágai Z, Sisson P R, Freeman R
Department of Clinical Microbiology, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Acta Microbiol Immunol Hung. 2000;47(4):433-43.
Simultaneous outbreaks of S. marcescens infection going on in the Neonatal Intensive Care Unit and the Surgical Department of the same hospital were investigated by pyrolysis mass spectrometry (PyMS). The PyMS analysis of the strains clearly demonstrated that the two outbreaks were caused by different strains. The 14 S. marcescens isolates from the first outbreak were closely related, with the exception of one environmental isolate, which did not harbour the ESBL plasmid, which was present in all other isolates. However, the phage type of all 14 isolates was the same. Among the 9 S. marcescens isolates from the second outbreak, PyMS clearly distinguished 3 that exhibited gentamicin resistance from the remaining 6 gentamicin-susceptible isolates. Phage typing was unhelpful in this case, as none of the isolates were typable. The PyMS typing of nosocomial outbreak strains can reach the level of discrimination approaching that achieved by molecular genetic analysis.
采用热解质谱法（PyMS）对同一家医院新生儿重症监护病房和外科同时爆发的粘质沙雷氏菌感染进行了调查。对菌株的PyMS分析清楚地表明，这两起疫情是由不同菌株引起的。第一次疫情中的14株粘质沙雷氏菌分离株密切相关，但有一株环境分离株除外，该分离株未携带ESBL质粒，而所有其他分离株均携带该质粒。然而，所有14株分离株的噬菌体类型相同。在第二次疫情的9株粘质沙雷氏菌分离株中，PyMS清楚地将3株对庆大霉素耐药的分离株与其余6株对庆大霉素敏感的分离株区分开来。在这种情况下，噬菌体分型没有帮助，因为没有一株分离株可分型。医院感染爆发菌株的PyMS分型能够达到接近分子遗传学分析的鉴别水平。
