Open AccessRapid and quantitative detection of blood Serratia marcescens by a real‐time PCR assay: Its clinical application and evaluation in a mouse infection model
Author(s) -
Iwaya Akira,
Nakagawa Saori,
Iwakura Nobuhiro,
Taneike Ikue,
Kurihara Mizuki,
Kuwano Tomoko,
Gondaira Fumio,
Endo Miyoko,
Hatakeyama Katsuyoshi,
Yamamoto Tatsuo
Publication year - 2005
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/j.femsle.2005.05.041
Subject(s) - serratia marcescens , microbiology and biotechnology , case fatality rate , outbreak , biology , medicine , virology , escherichia coli , gene , epidemiology , biochemistry
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.