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

Abstract

Introduction. Non-typhoidal Salmonella (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 Salmonella enterica subspecies serovar Corvallis. Thus, S. enterica 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 S. enterica 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.

Genotypic and Phenotypic Characterization of Antimicrobial Resistance Profiles in Non-typhoidal Salmonella enterica Strains Isolated From Cambodian Informal Markets

“…The resistance pattern observed over multiple studies demonstrates that the AMR profile of S. Corvallis has remained similar and reoccurring over the past decade in Southeast Asian countries (e.g., Cambodia and Thailand). S. Corvallis has been reported as a common causative agent for travel-associated salmonellosis in patients that traveled to Southeast Asia, indicating that this serotype has recurrently caused disease ( Ekdahl et al, 2005 ; Taguchi et al, 2009 ; Koch et al, 2011 ; Nakakubo et al, 2019 ).…”

A case report of Salmonella enterica serovar Corvallis from environmental isolates from Cambodia and clinical isolates in the UK

“…In fact, S. Corvallis is among the top 10 most frequently isolated serotypes from human patients in Southeast Asia [3]. For example, a case of travel-related bacteraemia caused by S. Corvallis was reported in an immunocompetent adult from Japan who had travelled to Cambodia and Vietnam prior the beginning of symptoms [5]. These reports indicate that this serovar may be endemic in geographical areas of Asia.…”

“…S. Corvallis from clinical isolates have been reported in the USA (in 2014, 2016 and 2017) and in the UK (in 2014, 2015, 2016, 2017, 2018 and 2019) for many consecutive years, indicating that this lineage poses a recurrent threat of infection in humans. Although S. Corvallis has caused bacteraemia and diarrhoeal disease [5,12], few studies have investigated its source of contamination and routes of transmission. Therefore, public health will benefit if future studies focus on the contamination and transmission routes of this pathogen.…”

“…Furthermore, S. Corvallis has been identified as a common causative agent for travel-related salmonellosis (i.e. travel to Southeast Asian countries) by numerous public health institutes [5,[10][11][12].…”

“…Salmonella are ubiquitous bacteria, with over 2500 different serovars reported to date [2]. A pathogenic serovar of interest, Salmonella enterica serovar Corvallis (S. Corvallis), has been reported worldwide in humans and food products [3][4][5][6], and is among the top 10 most frequently isolated serovars from human patients in Southeast Asia [3].…”