The genus Raoultella belongs to the family of Enterobacteriaceae. Raoultella spp. are Gram-negative, aerobic, non-motile rods. This genus can be distinguished from the genus Klebsiella, in that genus use histamine as the only source of carbon in the medium. Also, Raoultella grow at 4 °C and do not produce gas from lactose at 44.5 °C. Raoultella sp. is known to inhabit natural environments (water, soil, plants). The reservoir of Raoultella is the gastrointestinal tract and upper respiratory tract. Raoultella spp. are opportunistic bacteria, which usually cause infections of the biliary tract, pneumonia and bacteraemia in oncologic and with lower immunity patients. Raoultella planticola and Raoultella ornithinolytica are the most frequently encountered human pathogens among the genus Raoultella. In this review, the current knowledge on Raoultella infections is summarized.

Raoultella spp. representatives are Gram-negative capsulated, nonmotile rods. These bacteria are found in the natural environment: plants, water, soil and insects. R. ornithinolytica is one of the three species of Raoultella. R. ornithinolytica is the only species within the genus which has the ability to produce ornithine decarboxylase. Human infections related to R. ornithinolytica are exceedingly rare. The present case report describes catheter-related blood stream infection caused by R. ornithinolytica and successfully treated with antibiotic therapy.

The epidemiology of VIM/IMP-producing Enterobacteriaceae in Poland has revealed a remarkable number of specific or novel characteristics of the organisms, with some possible links to other mid-southern European countries.