通过实时PCR检测法快速定量检测血液中的粘质沙雷氏菌：其在小鼠感染模型中的临床应用及评估

Rapid and quantitative detection of blood Serratia marcescens by a real-time PCR assay: its clinical application and evaluation in a mouse infection model.

作者信息

Iwaya Akira, Nakagawa Saori, Iwakura Nobuhiro, Taneike Ikue, Kurihara Mizuki, Kuwano Tomoko, Gondaira Fumio, Endo Miyoko, Hatakeyama Katsuyoshi, Yamamoto Tatsuo

机构信息

Division of Bacteriology, Department of Infectious Disease Control and International Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan.

出版信息

FEMS Microbiol Lett. 2005 Jul 15;248(2):163-70. doi: 10.1016/j.femsle.2005.05.041.

DOI:10.1016/j.femsle.2005.05.041

PMID:15964718

Abstract

Large-scale nosocomial outbreaks of Serratia marcescens septicaemia in Japan have had a fatality rate of 20-60% within 48 h. As a countermeasure, a real-time PCR assay was constructed for the rapid diagnosis of S. marcescens septicaemia. This assay indeed detected S. marcescens in clinical blood specimens (at ca. 10(2)CFU ml(-1)), at a frequency of 0.5% in suspected cases of septicaemia. In mice, the assay provided estimates of blood S. marcescens levels at various infectious stages: namely, 10(7) to 10(8)CFU ml(-1) at a fatal stage (resulting in 100% death), 10(4)-10(5)CFU ml(-1) at a moderately fatal stage (resulting in 50% or more death), and <10(3)CFU ml(-1) at a mild stage (resulting in 100% survival), consistent with actual CFU measurements. Blood bacterial levels could be an important clinical marker that reflects the severity of septicaemia. The simultaneous detection of S. marcescens and the carbapenem resistance gene was also demonstrated.

摘要

在日本，粘质沙雷氏菌败血症的大规模医院内暴发在48小时内的死亡率为20%-60%。作为一项应对措施，构建了一种实时PCR检测法用于快速诊断粘质沙雷氏菌败血症。该检测法确实在临床血液标本中检测到了粘质沙雷氏菌（约10²CFU/ml），在疑似败血症病例中的检出频率为0.5%。在小鼠中，该检测法提供了不同感染阶段血液中粘质沙雷氏菌水平的估计值：即，在致死阶段（导致100%死亡）为10⁷至10⁸CFU/ml，在中度致死阶段（导致50%或更多死亡）为10⁴-10⁵CFU/ml，在轻度阶段（导致100%存活）<10³CFU/ml，这与实际CFU测量结果一致。血液细菌水平可能是反映败血症严重程度的重要临床指标。同时还证明了可同时检测粘质沙雷氏菌和碳青霉烯耐药基因。