Outbreak of KPC-3-producing, and colistin resistant, Klebsiella pneumoniae infections in two Sicilian hospitals.

We report the first outbreak caused by colistin-resistant Klebsiellapneumoniae producing KPC-3 carbapenamase in two Italianhospitals. This spread occurred in 1 month, and was caused byeight colistin-resistant and carbapenem-resistant Klebsiellapneumoniae isolates from eight patients. A further three isolateswere obtained from the intestinal tract and pharyngeal colonization.All isolates were multidrug-resistant (MDR), including being resistantto colistin, but they were susceptible to gentamicin and tigecycline.PCR detection showed that all isolates harboured the blaKPC-3 geneassociated with blaSHV-11, blaTEM-1 and blaOXA-9. All K. pneumoniaeisolates, genotyped by pulsed-field gel electrophoresis andmultilocus sequence typing, belonged to the same sequence type(ST)258 clone. From our data and a review of the internationalliterature, K. pneumoniae ST258 seems to be the most widespreadgenetic background for KPC dissemination in Europe.