Yokenella regensburgei infection in an immunocompetent individual after trauma following a fall from a personal conveyance

Abstract

BACKGROUND: Yokenella regensburgei infections have been documented in several immunocompromised individuals with num-erous associated risk factors including soft tissue infections, organ transplants, and metabolic disorders. Our report presents a rare case of Y. regensburgei infection in an immunocompetent individual. METHODS: In September 2020, a 38-year-old man who was otherwise healthy fell from a personal conveyance causing a puncture of his elbow. Two months later, he was admitted to the hospital with a chronic draining wound on his left arm with no fever (36.7°C) and stable vital signs. The patient underwent white blood cell (WBC) imaging, and single-photon emission computed tomography (SPECT/CT) to rule out osteomyelitis. Incision and drainage were performed, and the collected fluid was sent to a microbiology lab for culture diagnosis. Subsequently, matrix-assisted laser de-sorption/ionization time-of-flight (MALDI-TOF) analysis and antimicrobial susceptibility testing were performed. RESULTS: A WBC image and SPECT/CT test showed an increase in WBC uptake and activity in the subcutaneous tissue of the left arm. The culture diagnosis identified the isolate as Y. regensburgei and the patient received 2 weeks of sulfamethoxazole 800 mg and trimethoprim 160 mg orally twice daily based on the results of the antimicrobial susceptibility testing. He demonstrated clinical improvements shown through wound healing and reduced pain. CONCLUSION: This report supports the potential of Y. regensburgei to act as an opportunistic pathogen even in hosts with no prior underlying diseases or conditions.