EPIDEMIOLOGIC TYPING OF KLEBSIELLA-PNEUMONIAE BY PYROLYSIS MASS-SPECTROMETRY

Thirteen isolates of ceftazidime-resistant Klebsiella pneumoniae from a suspected cross-infection outbreak involving patients on an intensiv e care unit and a haematology ward were examined in pyrolysis mass spe ctrometry (PV-MS), along with eight concurrent non-outbreak-associated clinical isolates of klebsieliae as controls. Py-MS showed tight clus tering of the suspected outbreak isolates, suggesting cross-infection with a single strain. Non-outbreak isolates were clearly distinct from one another and from the outbreak strain. The results confirm that Py -MS is a powerful tool for rapid strain comparison in investigations o f cross-infection incidents.