Plesiomonas shigelloides Septic Shock Following Ingestion of Dojo Nabe (Loach Hotpot)

Recent Records on Bacterial Opportunistic Infections via the Dietary Route

This narrative review was aimed at identifying the opportunistic bacterial pathogens that can be transmitted by contaminated food and represent a current threat for patients particularly susceptible to infections because of underlying conditions or predisposing factors. The analysis was focused on recent case or outbreak reports and systematic reviews published in the years 2019 to 2023 and resulted in sorting 24 bacterial groups comprising the genera or species able to cause a variety of systemic or invasive infections if ingested with food or drinking water. These included both bacteria known to cause mild infections in immunocompetent persons and bacteria considered to be innocuous, which are used in food fermentation or as probiotics. No recent cases of infections transmitted through dietary routes were reported for the critical nosocomial pathogens widely found in food products, primarily Acinetobacter baumannii and Klebsiella pneumoniae. However, the very first sources of their introduction into the clinical environment still need to be established. In many instances, risky dietary habits, such as eating raw fish, seafood, raw meat, unpasteurized milk, and their derived products or the lack of control in fermentation processes, has led to the reported illnesses, pointing out the necessity to improve the hygiene of production and consumer awareness of the risks.

Clinical and microbiological features of intratumor abscess with bloodstream infection caused by Plesiomonas shigelloides, Citrobacter freundii, Streptococcus mitis/oralis, Clostridium perfringens, and Candida albicans in a patient with cholangiocarcinoma: A case report

Plesiomonas shigelloides is a gram-negative facultative anaerobic bacillus, usually found in soil and freshwater, which causes self-limited diarrhea, although reports of bacteremia are rare. Here, we report the first case of an intratumoral abscess with mixed bacteremia caused by P. shigelloides, Citrobacter freundii, Streptococcus mitis/oralis, Clostridium perfringens, and Candida albicans in a patient with recurrent postoperative cholangiocarcinoma. A 77-year-old man with hilar cholangiocarcinoma and hypertension was admitted to our hospital with fever and abdominal pain. He had visited Vietnam for 3 years, 20 years ago. Abdominal computed tomography showed air within the recurrent tumor at the left liver lobectomy resection margin site, which was diagnosed as an intratumor abscess perforating the intestinal tract. P. shigelloides, C. freundii, S. mitis/oralis, C. perfringens, and C. albicans were isolated in blood culture. P. shigelloides was identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and 16S ribosomal RNA (16S rRNA) sequencing. Piperacillin-tazobactam was administered for almost a week, ampicillin-sulbactam and levofloxacin for almost 3 weeks, and antifungal agents for almost 2 weeks, and the patient was discharged thereafter. Although bloodstream infections caused by P. shigelloides in patients with cancer are extremely rare, long-term colonization and the potential for future intra-abdominal infections were implicated.

Isolation, Identification, and Investigation of Pathogenic Bacteria From Common Carp (Cyprinus carpio) Naturally Infected With Plesiomonas shigelloides

Various bacterial diseases have caused great economic losses to the high-density and intensive aquaculture industry; however, the pathogenic mechanism underlying the large-scale challenged to caused by many bacteria remain unclear, making the prevention and treatment of these diseases difficult. In the present study, we isolated a bacterial strain from Cyprinus carpio having a typical bacterial disease and named it Cc2021. Through subsequent morphological observations, a regression challenge, biochemical identification, and 16S rRNA gene sequence analysis, we determined Cc2021 to be Plesiomonas shigelloides. Subsequently, we comprehensively investigated the pathogenicity of P. shigelloides in C. carpio through a regression challenge and assessed the underlying the pathogenic mechanism. Mortality results revealed that P. shigelloides is highly pathogenic and infects various tissues throughout the body, resulting in edema of the liver, spleen, and body and head kidneys. Histopathological analysis revealed obvious inflammation, bleeding, and necrosis in the intestine, spleen, and head kidney. The body’s immune tissues actively produce complement C3, superoxide dismutase, and lysozyme after a challenge to resist bacterial invasion. With regard to the underlying pathogenesis of P. shigelloides, comparative transcriptome analysis revealed 876 upregulated genes and 828 downregulated genes in the intestine of C. carpio after the challenge. Analysis of differentially expressed unigenes revealed the involvement of major immune pathways, particularly the TNF signaling pathway, interleukin (IL)-17 signaling pathway, and Toll-like receptor signaling pathway. The present study provides new valuable information on the immune system and defense mechanisms of P. shigelloides.