Juan Manuel García-Lechuz
Chronic otitis media (COM) is an inflammatory disease which affects the mucosal and bone structures of the medium ear, insidiously, slowly progressive, prone to persist and to produce severe sequelae. Staphylococcus aureus following by gram negative bacillus as Proteus spp., Klebsiella spp., Escherichia spp. and Haemophilus influenza are common pathogens causing COM. Recently some cases of COM produced by less known bacteria have been described. This is the case of the genus Kerstersia which has emerged in the literature causing bacteremia and urinary infection, as well as a causative pathogen of chronic otitis.
We have reviewed five cases as well as our own experience with an 88-year-old man transferred to our hospital suffering from persistent otorrhea, finally diagnosed as COM caused by Kerstersia gyiorum resistant to quinolones. Kerstersia genus belongs to the family Alcaligenaceae. A sample from the ear of our patient was taken and gram-negative rods were observed in the Gram stain. After incubation for 24 h, in all media, abundant slightly convex colonies with extended edges, colorful, were isolated and identified by MALDI-TOF (matrixassisted laser desorption ionization time-of-flight) Biotyper 3.1 as Kerstersia gyiorum (score of 2.3. K. gyiorum identification was confirmed by sequencing of the rRNA 16S gene and comparing of the sequence obtained with those deposited in GenBank with the NCBI BLASTn algorithm. Our case would be the third case resistant to quinolones reported in the literature.