Yersinia enterocolitica associated myopericarditis: case report and review of the literature.

We report a case of myopericarditis associated with Yersinia enterocolitica infection in an otherwise well 50-year-old man. We discuss the clinical features, microbiology and treatment of this rare cause of myopericarditis.

Metallacarborane Derivatives Effective against Pseudomonas aeruginosa and Yersinia enterocolitica.

Pseudomonas aeruginosa is an opportunistic human pathogen that has become a nosocomial health problem worldwide. The pathogen has multiple drug removal and virulence secretion systems, is resistant to many antibiotics, and there is no commercial vaccine against it. Yersinia pestis is a zoonotic pathogen that is on the Select Agents list. The bacterium is the deadliest pathogen known to humans and antibiotic-resistant strains are appearing naturally. There is no commercial vaccine against the pathogen, either. In the current work, novel compounds based on metallacarborane cage were studied on strains of Pseudomonas aeruginosa and a Yersinia pestis substitute, Yersinia enterocolitica. The representative compounds had IC50 values below 10 µM against Y. enterocolitica and values of 20-50 µM against P. aeruginosa. Artificial generation of compound-resistant Y. enterocolitica suggested a common mechanism for drug resistance, the first reported in the literature, and suggested N-linked metallacarboranes as impervious to cellular mechanisms of resistance generation. SEM analysis of the compound-resistant strains showed that the compounds had a predominantly bacteriostatic effect and blocked bacterial cell division in Y. enterocolitica. The compounds could be a starting point towards novel anti-Yersinia drugs and the strategy presented here proposes a mechanism to bypass any future drug resistance in bacteria.

A case of infective colitis due to Yersinia enterocolitica complicated by microliver abscesses mimicking multiple liver occult metastases: a case report.

BACKGROUND: We report an unusual case of infective colitis by Yersinia enterocolitica complicated by microliver abscesses mimicking multiple liver metastases in a 79 yr old female without any risk factors for bacteriaemia by this pathogen. CASE PRESENTATION: The patient was admitted to the Internal Medicine with Stroke Care ward of University Policlinico "P. Giaccone" in Palermo because of the appearance of diarrhoea. After the antimicrobial treatment for infective colitis, the clinicians observed a persistently increased white blood cells (WBC) count and multiple hepatic lesions; after having excluded any neoplastic disease and inflammatory bowel disease (IBD), blood cultures positive for Y. enterocolitica allowed to establish the final diagnosis was infective micro liver abscesses consequent to infective colitis due to Y. enterocolitica, which were successfully treated with cefixime and doxycycline. CONCLUSIONS: This case report should make clinicians reflect on how complex the differential diagnosis between microliver abscesses and metastasis could be and the possibility of bacteriaemia by Y. enterocolitica even without iron overload conditions.

Evaluation of the efficacy of enrofloxacin in rainbow trout (Oncorhynchus mykiss) following experimental challenge with Yersinia ruckeri.

BACKGROUND: Use of enrofloxacin in trout farms is reported, especially for the treatment of yersiniosis, albeit various dosing regimens have been used. Therefore, optimal doses should be investigated. METHODS: Five groups of 15 fish were challenged with Y. ruckeri. Two days later, three groups received feed containing enrofloxacin (ENR) at 1, 2.5 and 5 mg/kg fish respectively, during 7 days; one group received a single intraperitoneal injection of ENR at 10 mg/kg; and one group was left untreated. On day 15, surviving fish were euthanized. RESULTS: All fish survived in the group treated by injection, compared to 53%, 60% and 40% of the fish treated with 1, 2.5 and 5 mg/kg oral ENR, respectively, and 53% in the infected untreated group. CONCLUSION: A single intraperitoneal injection of ENR at 10 mg/kg seems more relevant than repeated oral administrations. The ENR oral doses used in trout farms should be revised.

Effects of Greek juniper (Juniperus excelsa) extract on immune responses and disease resistance against Yersinia ruckeri in rainbow trout (Oncorhynchus mykiss).

This study investigated the effects of Greek juniper extract on immune responses of rainbow trout. In this experiment, 4 doses [0 (Control), 1 (J1), 4 (J4) and 8 (J8) mg/kg] of the extract were administered orally using an oral gavage twice a day for 14 days. Immune responses were measured on 7th and 14th days. On 14th day, Yersinia ruckeri was injected intraperitoneally to all fish of all groups. On 14th day, ORP in fish of J1 group increased significantly. Lysozyme activity (LA) was increased in J8 group on 7th day (p < .05). On 14th day, a significant decrease was determined in J1 and J4 treatments in LA. Myeloperoxidase activity was significantly decreased in all groups irrespective of sampling times (p < .05). Interleukin (IL)-1ß was significantly elevated in fish of J8 group on 7th day. IL-8 increased in fish of J8 and J4 groups on 7th day of the study. IL-12 gene expression was significantly up-regulated in J8 fish group on 7th day, and in J4 fish group on 14th day. Survival rate was higher in J8 treatment compared to the control and other treatments (p < .05). The results suggest that Juniperus excelsa provides protection against Y. ruckeri in rainbow trout.

Bloodstream infection caused by Yersinia enterocolitica in a host with ankylosing spondylitis: a case report and literature review.

The extraintestinal infections caused by Yersinia enterocolitica are very rare, especially in the form of spontaneous bloodstream infection at people without history of blood transfusion. Their clinical symptoms and treatments are still not very clear for now. Here, we report a case of spontaneous bloodstream infection caused by Y. enterocolitica in a 56-year-old Chinese male. The patient presented to outpatient with fever for 1 week, he was diagnosed ankylosing spondylitis for 10 years, and suffered from the pain in his neck, lumbosacral region and limbs constantly. After 4 days of outpatient treatment, there was no sign of improvement so he admitted to inpatient department. Ceftriaxone and metronidazole were initiated in the previous 3 days, the temperature did not drop (highest temperature is 38.3 °C) and the limb joint pain was aggravated. On day 4, antibiotic therapy was changed to moxifloxacin as the growth of Y. enterocolitica showed in blood culture, then changed to amikacin and piperacillin/tazobactam according to culture susceptibility. The patient received a total of 24 days antibacterial treatment before discharge, his body temperature returned to normal, but he remains continuous pain in lumbosacral region and limbs after negative blood culture, which was considered to be caused by AS. Gastrointestinal symptoms such as vomiting, diarrhea and abdominal pain were not reported during the hospitalization, which usually appears in patients with Yersinia enterocolitica infection. We reviewed 12 septicemia cases without the history of blood transfusion from the literature. Not all hosts were under a low immunity or have a clear history of exposure. Clinical symptoms and antibiotic agents were also different from case to case. Physicians should consider the rare diagnosis of Y. enterocolitica infection in patients without clear history of exposure and typical symptoms. And distinguish between pain caused by AS and aseptic arthritis caused by Y. enterocolitica.

Rcs Phosphorelay Responses to Truncated Lipopolysaccharide-Induced Cell Envelope Stress in Yersinia enterocolitica.

Lipopolysaccharide (LPS) is the major component of the outer membrane of Gram-negative bacteria, and its integrity is monitored by various stress response systems. Although the Rcs system is involved in the envelope stress response and regulates genes controlling numerous bacterial cell functions of Yersinia enterocolitica, whether it can sense the truncated LPS in Y. enterocolitica remains unclear. In this study, the deletion of the Y. enterocolitica waaF gene truncated the structure of LPS and produced a deep rough LPS. The truncated LPS increased the cell surface hydrophobicity and outer membrane permeability, generating cell envelope stress. The truncated LPS also directly exposed the smooth outer membrane to the external environment and attenuated the resistance to adverse conditions, such as impaired survival under polymyxin B and sodium dodecyl sulfate (SDS) exposure. Further phenotypic experiment and gene expression analysis indicated that the truncated LPS was correlated with the activation of the Rcs phosphorelay, thereby repressing cell motility and biofilm formation. Our findings highlight the importance of LPS integrity in maintaining membrane function and broaden the understanding of Rcs phosphorelay signaling in response to cell envelope stress, thus opening new avenues to develop effective antimicrobial agents for combating Y. enterocolitica infections.

Molecular evaluation of quorum quenching potential of vanillic acid against Yersinia enterocolitica through transcriptomic and in silico analysis.

Introduction. Yersinia enterocolitica is one of the leading food-borne entero-pathogens causing various illnesses ranging from gastroenteritis to systemic infections. Quorum sensing (QS) is one of the prime mechanisms that control the virulence in Y. enterocolitica.Hypothesis/Gap Statement. Vanillic acid inhibits the quorum sensing and other virulence factors related to Y. enterocolitica. It has been evaluated by transcriptomic and Insilico analysis. Therefore, it can be a prospective agent to develop a therapeutic combination against Y. enterocolitica.Aim. The present study is focused on screening natural anti-quorum-sensing agents against Y. enterocolitica. The effect of selected active principle on various virulence factors was evaluated.Methodology. In total, 12 phytochemicals were screened by swarming assay. MATH assay, EPS and surfactant production assay, SEM analysis, antibiotic and blood sensitivity assay were performed to demonstrate the anti-virulence activity. Further, RNA sequencing and molecular docking studies were carried out to substantiate the anti-QS activity.Results. Vanillic acid (VA) has exhibited significant motility inhibition, thus indicating the anti-QS activity with MQIC of 400 µg ml-1 without altering the cell viability. It has also inhibited the violacein production in Chromobacterium violaceum ATCC 12472, which further confirms the anti-QS activity. VA has inhibited 16 % of cell-surface hydrophobicity (CSH), 52 % of EPS production and 60 % of surfactant production. Moreover, it has increased the sensitivity of Y. enterocolitica towards antibiotics. It has also made the cells upto 91 % more vulnerable towards human immune cells. The transcriptomic analysis by RNA sequencing revealed the down regulation of genes related to motility, virulence, chemotaxis, siderophores and drug resistance. VA treatment has also positively regulated the expression of several stress response genes. In furtherance, the anti-QS potential of VA has been validated with QS regulatory protein YenR by in silico molecular simulation and docking study.Conclusion. The present study is possibly the first attempt to demonstrate the anti-QS and anti-pathogenic potential of VA against Y. enterocolitica by transcriptomic and in silico analysis. It also deciphers that VA can be a promising lead to develop biopreservative and therapeutic regimens to treat Y. enterocolitica infections.

Heterogeneity of Highly Susceptible Yersinia enterocolitica Isolates of Clinical and Environmental Origin: A 5-Year Survey from Iran (2011-2016).

The aim of this study was to evaluate the resistance and virulence characteristics of Yersinia enterocolitica strains of clinical and environmental origins over a 5-year period in Iran and to determine the genetic diversity of strains using pulsed-field gel electrophoresis (PFGE) method. A total of 20 Y. enterocolitica strains were collected from 850 stool samples of patients with diarrhea, and 18 Yersinia spp. including 10 Y. enterocolitica were collected from water, food, and vegetable samples. The most frequently isolated Y. enterocolitica strains belonged to biotype (BT) 1A (83.33%). No Y. enterocolitica BT4 was detected that can be attributed to the absence of pig animal reservoir in Iranian food chain. The most frequent chromosomal virulence genes among the Y. enterocolitica isolates were inv (100%), ystA (67%), ystB (83%), tccC (20%), and ail (17%). The most frequent chromosomal virulence genes among non-enterocolitica Yersinia spp. isolates were ystB (87.5%), ystA (37.5%), and inv (37.5%). None of the Y. enterocolitica isolates harbored plasmid origin virulence genes. None of the isolates was resistant to ciprofloxacin, gentamicin, tetracycline, cotrimoxazole, and chloramphenicol, whereas 90% of the Y. enterocolitica and 62.5% of the Yersinia spp. strains were resistant to ampicillin. PFGE genotyping showed a heterogeneous population of highly susceptible Yersinia spp. in both clinical and environmental samples, putting forward a good prognosis in the treatment of patients with yersiniosis. The occurrence of biotype 1A with inv+ystA+ystB+ genotype in clinical strains implies the significance of inv, ystA, and ystB gene products in turning of naturally nonpathogenic biotype 1A strains into clinically important pathogens.

Protective effect of in-feed specific IgM towards Yersinia ruckeri in rainbow trout.

Tightened regulations and an environmentally friendly approaches in fish production have greatly reduced the use of antibiotics but green solutions are continuously being explored. The use of functional feed may have a potential in the aquaculture sector in securing biomass and minimizing the loss from disease. In the present study, we tested the concept that blood from the fish slaughterhouse can be used for mass purification of specific antibodies which subsequently can be used for feeding fish and thereby confer protection against diseases. IgM was purified from serum from Yersinia ruckeri vaccinated rainbow trout and an IgM sandwich ELISA was developed for quantification of rainbow trout IgM. The purified IgM was encapsulated in alginate microparticles and top-coated in fish feed. IgM re-extracted from the alginate microparticles was shown to retain high reactivity towards Y. ruckeri antigens indicating that its bioactivity remained intact after encapsulation. IgM release from the alginate microparticles was only observed at high pH (pH 8.2) and minimal at low pH, indicating protection of IgM at low pH in the fish stomach during passage. In a feeding - challenge experiment (feeding 1 week before Y. ruckeri challenge and for two weeks following challenge), a statistically non-significant 10% lower mortality was observed in the high dose (400 µg IgM/fish/day fed over 3 weeks) group.

Aporphinoid alkaloids as antimicrobial agents against Yersinia enterocolitica.

Foodborne diseases have become a health issue worldwide, mainly due to the consumption of contaminated foods that are either raw, improperly heat treated or cross-contaminated after adequate heat treatment foods. A group of alkaloids extracted from plants were tested to evaluate their antimicrobial effect against different strains of Yersinia enterocolitica and other foodborne bacteria. The results obtained reveal that oliveridine and pachypodanthine inhibited Y. enterocolitica growth, with MIC values of 25 µmol l-1 and 100 µmol l-1 respectively. The results indicated that both alkaloids are good growth inhibitors, but oliveridine showed greater inhibitory effect with lower MIC values. Inhibitory alkaloids can be developed as potential antimicrobials in food system to prevent or treat foodborne diseases, thus contributing to solve the global issue of contaminated food consumption. SIGNIFICANCE AND IMPACT OF THE STUDY: Alkaloids are abundant secondary metabolites in plants and represent one of the most widespread class of compounds endowed with multiple and varied pharmacological properties. In this work, we propose two aporphinoid alkaloids extracted from plants as new antimicrobial agents. Oliveridine and pachypodanthine inhibited Yersinia enterocolitica growth for up to 96 h of culture. This is the first reported study of the activity of these alkaloids as antimicrobial compounds.

Adjuvant efficacy of G2 (buffalo spleen extraction) against Yersinia septicemia in rainbow trout (Onchorhynchus mykiss).

Adjuvant effect of G2 (extraction of buffalo spleen) was assessed in intraperitoneally immunized rainbow trout (100-150 g) with killed- Y. ruckeri bacterin biotype I [0.1 mL (1 × 107 cells/fish) of vaccine diluted with the adjuvant in a ratio of 1:1 (V/V)] at 12.4 ±â€¯1.3 °C for 10 weeks. Leukocyte and lymphocyte counts, anti-Y. ruckeri antibody titer and relative percent survival (RPS) in fish vaccinated with vaccine containing the adjuvant were significantly higher than the immunized fish with Y. ruckeri antigen alone throughout the experiment (P < 0.05), but neutrophils count and lysozyme activity were mostly significantly higher in the latter group (P < 0.05). No difference was seen in the complement activity between vaccinated fish containing the adjuvant and vaccine alone (P > 0.05). The results of this work for the first time demonstrated that inclusion of G2 as an adjuvant in Y. urckeri vaccine can improve the efficacy of the vaccine against Yersinia septicemia in rainbow trout.

Enteropathogens and antibiotics. / Enteropatógenos y antibióticos.

Infectious gastroenteritis remains a public health problem. The most severe cases are of bacterial origin. In Spain, Campylobacter and Salmonella are the most prevalent bacterial genus, while Yersinia and Shigella are much less frequent. Most cases are usually self-limiting and antibiotic therapy is not generally indicated, unless patients have risk factors for severe infection and shigellosis. Ciprofloxacin, third generation cephalosporins, azithromycin, ampicillin, cotrimoxazole and doxycycline are the most recommended drugs. The susceptibility pattern of the different bacteria determines the choice of the most appropriate treatment. The aim of this review is to analyse the current situation, developments, and evolution of resistance and multidrug resistance in these 4 enteric pathogens.

Structural Insight into Inhibition of CsrA-RNA Interaction Revealed by Docking, Molecular Dynamics and Free Energy Calculations.

The carbon storage regulator A (CsrA) and its homologs play an important role in coordinating the expression of bacterial virulence factors required for successful host infection. In addition, bacterial pathogens with deficiency of CsrA are typically attenuated for virulence. In 2016, the first series of small-molecule inhibitors of CsrA-RNA interaction were identified, which were found to achieve the CsrA-RNA inhibition by binding to the CsrA, without interfering with the RNA. However, the binding mechanism of these inhibitors of CsrA is not known. Herein, we applied molecular docking, molecular dynamics and binding free energy calculations to investigate the binding mode of inhibitors to CsrA. We found that the G11(RNA)-binding site is the most important binding site for CsrA inhibitors. An inhibitor with the proper size range can bind to that site and form a stable complex. We also found that inhibitors with larger size ranges bind to the entire CsrA-RNA interface, but have loose binding. However, this loose binding still resulted in inhibitory activity. The calculated binding free energy from MM/GBSA has a good correlation with the derived experimental binding energy, which might be used as a tool to further select CsrA inhibitors after a first-round of high-throughput virtual screening.

Thirty years of human infections caused by Yersinia enterocolitica in northern Spain: 1985-2014.

Yersinia enterocolitica infection is a zoonosis with worldwide distribution, gastroenteritis being by far the most common clinical manifestation of human infection. In Gipuzkoa, northern Spain, human Y. enterocolitica infections increased from the mid-1980s to the beginning of the 21st century (from 7·9 to 23·2 annual episodes per 100 000 population) to decrease to 7·2 annual episodes per 100 000 population in the last years of the study. The hospital admission rate due to yersiniosis during the last 15 years of the study was 7·3%. More than 99% of isolates were serotype O:3. Infection affected mainly children under 5 years of age (average rate: 140 episodes per 100 000 population). The incidence in adults was low but hospitalisation increased with age, exceeding 50% in people over 64 years old.

Reactive Arthritis.

Reactive arthritis is classified as a spondyloarthropathy. Current concepts of disease suggest an infectious trigger, followed by inflammatory arthritis. Several mechanisms have been proposed to explain the interaction of host susceptibility and microorganism. Diagnosis relies on a compatible clinical syndrome and microbiologic confirmation of the pathogen. Antibiotic therapy seems useful in Chlamydia-triggered arthritis. The role of antibiotics in arthritis triggered by enteric pathogens is less clear. The role of tumor necrosis factor alpha inhibitors in therapy is evolving. Many patients have a course limited to a few months, but others experience extraarticular disease and more prolonged courses.

Sepsis and siderosis, Yersinia enterocolitica and hereditary haemochromatosis.

A 60-year-old woman was admitted with sepsis, relative bradycardia, CT evidence of numerous small liver abscesses and 'skin bronzing' consistent with hereditary haemochromatosis (HH). Yersinia enterocolitica O:9 infection was confirmed by serology specimens taken 10 days apart. Iron overload was detected, and homozygous C282Y gene mutation confirmed HH. Liver biopsy revealed grade IV siderosis with micronodular cirrhosis. Haemochromatosis is a common, inherited disorder leading to iron overload that can produce end-organ damage from excess iron deposition. Haemochromatosis diagnosis allowed aggressive medical management with phlebotomy achieving normalisation of iron stores. Screening for complications of cirrhosis was started that included hepatoma surveillance. Iron overload states are known to increase patient susceptibility to infections caused by lower virulence bacteria lacking sophisticated iron metabolism pathways, for example, Yersinia enterocolitica Although these serious disseminated infections are rare, they may serve as markers for occult iron overload and should prompt haemochromatosis screening.