Bacterial skin infection caused by a plant pathogen Kosakonia cowanii: identification with the MALDI Biotyper sirius one and susceptibility testing.

Kosakonia cowanii is a Gram-negative bacillus belonging to the order Enterobacterales. K. cowanii is a plant pathogen; we report the isolation of this organism from a gardening puncture injury from a plant. Pus examined from the site of infection showed the infecting organism as K. cowanii by MALDI-TOF MS Biotyper Sirius One and 16S rRNA analysis. The organism failed to be identified biochemically by the Vitek 2 XL identification system as Kosakonia spp. The Gram-negative bacilli on the system were biochemically identified as Pantoea spp. Difficulties in species identification biochemically suggest that K. cowanii might potentially represent an underestimated opportunistic human pathogen in skin infections associated with plant injuries. The MALDI-TOF MS Biotyper Sirius One software was found to be a fast and reliable identification of the organism. The isolate was found to be susceptible to first-generation cephalosporins, both cefalexin and cefazolin, by disc diffusion and Vitek 2 XL, even though antibiotic breakpoints currently do not exist using European Committee on Antimicrobial Susceptibility Testing or Clinical and Laboratory Standards Institute (CLSI) guidelines for this organism.