Identification of Pigmentibacter ruber in the peripheral blood of a drowning patient: a case report and literature review

Pigmentibacter ruber is a newly described opportunistic pathogen with a high case-fatality rate, necessitating comprehensive case documentation and systematic analysis. We report the case of a 61-year-old male drowning patient who presented with respiratory failure and septic shock. Blood cultures obtained during hospitalization became positive only after prolonged incubation (92 h); however, the causative Gram-negative rod could not be identified by routine methods, including mass spectrometry. Subsequent 16S rRNA gene and whole-genome sequencing definitively identified the organism as Pigmentibacter ruber . This case adds to the small number of reported cases of P. ruber bloodstream infection in drowning patients. It raises the possibility, which has not yet been confirmed by environmental sampling, that exposure to freshwater may be associated with P. ruber infection. Because all cases reported to date originate from Asia, however, this distribution may reflect reporting patterns rather than a true geographic predilection. Not applicable.