A case of primary bacteraemia caused by serovar Corvallis in an immunocompetent adult after travel to Southeast Asia.

Introduction: Non-typhoidal (NTS) that typically causes diarrhoeal disease in humans has a dramatically more severe and more invasive presentation than typhoid fever in immunocompromised adults. However, the incidence and significance of NTS primary bacteraemia in immunocompetent adults have been unclear.

Case Presentation: A 24-year-old man presented to our hospital with a high fever 14 days after travelling to Vietnam and Cambodia for 14 days. His past medical history, family history and social history were unremarkable, except for his dietary intake history during his stay in Southeast Asia. He did not have any abdominal pain, diarrhoea, enterocolitis, arthritis, or abscesses, as determined by multiple examinations, which included computed tomography. The initial blood cultures identified the presence of Gram-negative bacilli, which were finally identified as the subspecies serovar Corvallis. Thus, serovar Corvallis was the most likely primary bacteria in this patient. Since domestic outbreaks of NTS infections are extremely rare, our case patient was diagnosed with travel-related bacteraemia. The patient had an uneventful recovery after antibiotic administration.

Conclusion: We report a rare case of bacteraemia caused by serovar Corvallis in an immunocompetent adult after travelling through Vietnam and Cambodia. From the experience of our case, we suggest that more caution is necessary when diagnosing the unique clinical features of travel-related NTS infections.