Kerstersia gyiorum infection in a patient with chronic suppurative otitis media identified by whole genome sequencing: a case report

A 52-year-old female patient suffering from chronic suppurative otitis media had a bacterial strain isolated from her ear swab specimens, which could not be identified using conventional methods, but it was eventually identified as Kerstersia gyiorum via whole genome sequencing (WGS). Antimicrobial drug susceptibility testing was conducted on the isolated strain and the results demonstrated its susceptibility to a range of antimicrobial drugs, including ofloxacin, ceftriaxone, and other agents. However, resistance to chloramphenicol was observed. The patient was treated with ofloxacin, ceftriaxone, and dexamethasone, resulting in an improvement in symptoms. This report describes the first documented case of Kerstersia gyiorum causing chronic suppurative otitis media in China. WGS provided definitive species identification in which conventional methods failed, demonstrating its critical role in diagnosing atypical pathogens.