The value of pyrolysis mass spectrometry to investigate nosocomial outbreaks caused by Serratia marcescens

Elisabeth Nagy, Zsófia Koczián, Z. Prágai, Penelope R. Sisson, R. Freeman

Research output: Contribution to journalArticle


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.

Original languageEnglish
Pages (from-to)433-443
Number of pages11
JournalActa microbiologica et immunologica Hungarica
Issue number4
Publication statusPublished - Dec 1 2000



  • Nosocomial outbreaks
  • Pyrolysis mass spectrometry
  • Serratia marcescens

ASJC Scopus subject areas

  • Immunology and Microbiology(all)

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