Gastrointestinal Pathogens Research Articles

The RNA Chaperone Protein ProQ is a pleiotropic regulator in enteropathogenic Escherichia coli

Enteropathogenic Escherichia coli (EPEC) is a gastrointestinal pathogen that affects individuals of all age groups, with infections ranging from subclinical colonization to acute or persistent diarrhea. The bacterium’s ability to cause diarrhea depends on the locus of enterocyte effacement (LEE) pathogenicity island. Although regulation of the LEE has been systematically characterized, until the last decade, these studies were limited to transcriptional control. Posttranscriptional regulation of the LEE is an underappreciated and understudied area of gene regulation. In the past few years, multiple reports have shed light on the roles of RNA-binding proteins, such as Hfq and CsrA, that modulate virulence in EPEC. This study was undertaken to explore the role of another RNA chaperone protein, ProQ, in the pathophysiology of EPEC. Our results suggest that deletion of proQ globally derepresses gene expression from the LEE in lysogeny broth (LB) suggesting that ProQ is a negative regulator of the LEE. Further interrogation of the role of ProQ in regulating the LEE-encoded type III secretion system revealed that ProQ globally silences the LEE by downregulating the expression of PerC – a prominent transcriptional activator of the LEE master regulator ler, which, in turn leads to the observed repression from the other LEE operons. Furthermore, ProQ appears to moonlight as it affects other physiological processes including type IV pili biogenesis, flagellar-motility, biofilm formation, tryptophan metabolism, and antibiotic resistance. Our study provides the very first evidence to implicate ProQ as a pleiotropic regulator in EPEC.

The primiparous IgA and IL-5 colostrum concentration based on maternal factor: corroborate the inflammation pathways to IgA colostrum synthesis.

Immunoglobulin A (IgA) plays a crucial role in the maturation the neonatal mucosal barrier. The accumulation of IgA antibody-secreting cells (ASCs) in the lactating mammary gland facilitates the secretion of IgA antibodies into milk, which are then passively to the suckling newborn, providing transient immune protection against gastrointestinal pathogens. Physiologically, full-term infants are unable to produce IgA, required for mucosal barrier maturation for at least 10 days after birth. Prior studies declare that interleukin 5 (IL-5) responsible to encourage of IgA-producing B cells maturation during lactating periods. This purpose of this study was determine IgA and IL-5 colostrum concentration based on maternal factors. Ninety primiparous with full-term pregnancy and vaginal delivery were enrolled in a cross-sectional study. Colostrum samples were collected on the first day after delivery, followed by the measurement of IgA and IL-5 concentrations using ELISA. Sociodemographic and maternal factors were recorded based on participants' self-reports using a questionnaire. The results showed that mean of colostrum IgA concentration in primiparous 24.9 ± 0.3 years old (95%CI: 24.3-25.6) was 1.51 ± 0.15µg/mL, while colostrum IL-5 concentration was 82.37 ± 20.2pg/mL. The results showed that IgA levels were not significantly correlated with age, education, occupation, weight, height, body mass index (BMI), fish consumption, or smoking habits but were significantly related to baby sex disappointment and weight gain during pregnancy (P<.05). Meanwhile, the IL-5 concentration was significantly correlated with smoking habits, baby's birth weight, and maternal age. The composition of IgA and IL-5 in breast milk is strongly associated with several maternal factors including baby sex disappointment, weight gain during pregnancy, smoking habits, baby's birth weight, and maternal age. This maternal factor corroborate the recently evidence refer to inflammatory pathways involvement in colostrum IgA synthesis.

P-1629. Reduction in Clostridioides difficile Over-diagnosis Following Suppression of C. difficile Target from Multiplex Molecular Stool Assay in a Pediatric Healthcare System

Abstract Background Clostridioides difficile testing by polymerase chain reaction (PCR) does not differentiate asymptomatic colonization from infection, and children are frequently colonized with toxigenic strains of C. difficile. Over-diagnosis of C. difficile infections can lead to adverse patient outcomes and poorer quality metrics for hospitals.Figure 1:C. difficile PCR orders following change in GI PCR Panel, Interrupted Time Series Methods In January 2023 our pediatric health system enacted multimodal changes to the electronic ordering of stool tests for C. difficile and other gastrointestinal pathogens. A multiplex PCR test for stool was updated to suppress testing for toxigenic C. difficile. The only remaining method to test for C. difficile by PCR in house was a C. difficile toxin gene specific PCR. Additionally, appropriate clinical criteria with a hard stop were added to the C. difficile PCR order (all of: no laxatives in the past 24 hours, at least 3 liquid stools in the past 24 hours, at least one risk factor for C. difficile infection, and patient at least one year old). If providers still sought C. difficile testing without meeting these criteria, infectious disease specialist approval was required. We analyzed the effect of this intervention using interrupted time series analysis and pre-post aggregate rates from January 2019 through February 2024.Figure 2:C. difficile positive rate following change in GI PCR Panel, Interrupted Time Series Results There were 4426 stool PCR tests performed for C. difficile in the pre-intervention period and 622 in the post-intervention period. The mean (± sd) age of those tested was 7.8 years (± 6.1 years). After the intervention, there was an immediate 61% decrease in C. difficile testing incidence (95% CI [53% - 67%], Figure 1) and 51% decrease in C. difficile diagnosis incidence (95% CI [26% - 67%], Figure 2). There was no significant immediate change or change in slope in the C. difficile antibiotic treatment incidence or HFO C. difficile incidence, but there was a trend towards lower rates of healthcare facility onset C. difficile after the change (aggregate rate 4.13 per 10,000 non-NICU patient-days prior to intervention vs. 3.39 after, P = .28). Conclusion Removing C. difficile from multiplex PCR assays and adding required clinical criteria to the electronic order reduces the number of C. difficile tests and diagnoses in a pediatric health system. Disclosures Laura Filkins, PhD, Avsana Labs: Board Member|Avsana Labs: Stocks/Bonds (Private Company)|Biofire Diagnostics: Grant/Research Support

P-1924. Impact of the SARS-CoV-2 Pandemic on Medically Attended Acute Gastroenteritis Incidence and Health Care Utilization in the U.S

Abstract Background The SARS-CoV-2 pandemic has altered the epidemiology of certain infectious diseases and general utilization of health care services. The goal of this work was to compare the incidence and characteristics of medically attended acute gastroenteritis (MAAGE) prior to and since the pandemic within the Kaiser Permanente Northwest (KPNW) integrated health care delivery system in the US. Overall incidence of medically attended acute gastroenteritis among Kaiser Permanente Northwest members, by month, September 2017-February 2024 Methods We identified MAAGE encounters (remote, outpatient [OP], emergency department [ED] and inpatient [IP]) among KPNW members of all ages, from 9/2017-2/2024, using diagnostic codes in the electronic health record. Encounters separated by &amp;lt; 30 days were considered a single episode and assigned to the highest encounter severity. We included laboratory testing for gastrointestinal (GI) pathogens performed three days prior to three days after MAAGE encounters and reported on norovirus positivity. Incidence of medically attended acute gastroenteritis among Kaiser Permanente Northwest members, by age and month, September 2017-February 2024 Results After a significant decline in early 2020 associated with the start of the pandemic, overall MAAGE incidence rebounded such that the rate observed from 3/23-2/24 (81.6 per 1,000 person years) was similar to that from 3/18-2/20 (80.3 per 1,000 person years; Fig. 1). MAAGE incidence was highest among those 0-4 and 75+ years; however, we observed different patterns between the two periods. Beginning in late 2021, incidence among those 0-4 years returned to, and periodically exceeded, pre-pandemic rates, while that among those 75+ fell below those levels (Fig. 2). Compared to the pre-pandemic era, and since 9/21, a lower proportion of MAAGE episodes had clinical testing for GI pathogens (7.0% vs 8.2%; Fig. 3), a greater proportion were managed remotely (27% vs 15%), and a lower proportion were managed in the OP setting (43% vs. 54%; Fig. 4) p&amp;lt; 0.0001 for all three. We observed no difference in proportions managed in ED (24%) and IP (6%) settings. Among tested episodes, norovirus positivity rebounded since its nadir in 2020. Figure 3 Proportion of overall medically attended acute gastroenteritis episodes for which gastrointestinal pathogen testing was performed, and the proportion positive for norovirus, September 2017-February 2024 Conclusion Four years after the pandemic began, the epidemiology of MAAGE has largely returned to pre-pandemic levels. At the same time, the shift to greater remote management of MAAGE, with lower rates of diagnostic testing, appears to be sustained. New estimates of the burden of MAAGE on the population and the health care system are required in this changed landscape. Figure 4 Distribution of medically attended acute gastroenteritis episodes, by location of medical care, September 2017-Feburary 2024 Disclosures Mark A. Schmidt, PhD, MPH, HilleVax: Grant/Research Support|Janssen: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support|Vir Biotechnology: Grant/Research Support Matthew T. Slaughter, MS, Moderna: Grant/Research Support John F. Dickerson, PhD, Janssesn: Grant/Research Support|Moderna: Grant/Research Support|Novartis: Grant/Research Support|Pfizer: Grant/Research Support Holly C. Groom, MPH, Hillevax: Grant/Research Support|Moderna: Grant/Research Support Judy L. Donald, MA, HilleVax: Grant/Research Support|Janssen: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support|Vir Biotechnology: Grant/Research Support Maureen O'Keeffe-Rosetti, MS, Hillevax: Grant/Research Support|Janssen: Grant/Research Support|Moderna: Grant/Research Support|Pfizer: Grant/Research Support Laura H. Hendrix, MS, Moderna: Employment|Moderna: Stocks/Bonds (Private Company) Katherine B. Carlson, PhD, MPH, Moderna: Stocks/Bonds (Private Company) Emma Viscidi, PhD, MHS, Moderna: Stocks/Bonds (Public Company)

P-1616. Treatment Rates of Patients with Toxin Negative, PCR Positive C.difficile After a Change in Reflex Testing Order

Abstract Background On 12/11/23, our academic medical center changed from primarily GDH antigen/toxin A/B combination testing with reflex to C. difficile PCR in discordant samples (Figure 1) to PCR (either direct or from a multiplex gastrointestinal pathogen panel (GIPP)) as initial screening with positive specimens reflexed to antigen/toxin testing (Figure 2). After the algorithm change, we evaluated treatment rates for patients with positive PCR results who tested negative for C. difficile toxin. Methods New guidance for C. difficile infection (CDI) was posted on the Antimicrobial Stewardship website and education was provided to clinicians on the algorithm. Data was collected for inpatients ≥ 19 years old who were toxin negative, but antigen and PCR test positive for C. difficile from 10/1/22-3/31/24. GIPP could be ordered first during the entire period, but only in the first 3 hospital days. Treatment and recurrence rates for patients having a PCR test first were analyzed compared to rates for those with initial antigen/toxin tests. Treatment was counted if initiated within 2 days of test and continued ≥ 5 days, according to proposed NHSN definitions, and included oral vancomycin, fidaxomicin, or metronidazole if vancomycin was contraindicated. Based on estimated treatment rates, a sample size of 177 patients was targeted to detect a change from 80% to 60% treatment. Results Out of 179 discordant CDI results prior to the testing change, treatment occurred in 151 (85.4%) cases. After the change, treatment was prescribed 26 out of 46 (56.5%) times, a 34% reduction (p&amp;lt; 0.01). Baseline characteristics were similar in each group, and 56.9% of tests were ordered in the first 3 days of hospital stay. Overall, when an antigen test was performed first and a positive PCR reported last, treatment occurred in 84 of 91 (92.3%) cases. When a PCR test was performed first and a negative toxin resulted last, treatment was prescribed in 93 of 134 (69.4%) cases (p&amp;lt; 0.01). Treatment was the same in each group (99% vancomycin). Recurrence rates were similar regardless of testing order, 5.4% with antigen first vs. 4.4% with PCR test first. Conclusion Treatment rates for patients with discordant CDI results were significantly lower after the order of testing changed and when a negative toxin result was presented last. Disclosures Trevor C. Van Schooneveld, MD, FSHEA, FIDSA, AN2 Therapeutics: Grant/Research Support|BioMerieux: Grant/Research Support|BioMerieux: Honoraria|Thermo-Fisher: Honoraria

P-2080. Impact of the Implementation of Multiplex Gastrointestinal PCR Panel on Antimicrobial Use for Infectious Diarrhea

Abstract Background Rapid molecular methods, such as BioFire FilmArray™ Gastrointestinal (GI) Panel, have become common in clinical practice. The GI Panel identifies 22 GI pathogens in approximately 1 hour. We evaluated antimicrobial prescribing before and after the implementation of the GI Panel to see the impact on appropriate prescribing for infectious diarrhea and to identify quality improvement areas for antimicrobial stewardship moving forward.Figure 2:Percent Type of Antibiotic Change After Result of Diagnostic Testing Methods This retrospective cohort analysis compared antimicrobial prescribing practices for infectious diarrhea one year before and after the implementation of the BioFire GI Panel at the University of Maryland Medical Center (UMMC) in August 2021. Prior to GI Panel implementation at UMMC, the major diagnostic tests for infectious diarrhea were stool culture, ova and parasite smear, and a parasite PCR. Cases were randomly selected with an even distribution from each month from August 2019 to August 2022. Appropriateness of empiric and definitive management was assessed based on diarrhea type (bloody, acute, or prolonged), the patient's immune status, travel history, clinical presentation, and antibiotic selection. Results 353 patients were included: 179 pre-GI panel implementation and 174 post-implementation. Empiric antibiotic therapy for infectious diarrhea was started in 47/179 (26.3%) of the pre-panel group and 50/174 (28.7%) of the post-panel (P = 0.601). The diagnostic tests resulted in positive organism identification in 10% of patients in the pre-group, while positive identification increased to 19.4% post-group (P = 0.012). When an organism was identified, 12/33 (66.7%) of the post-panel group received antibiotic therapy, while only 6/18 (33.3%) of the pre-panel group received antibiotics (P = 0.83) Conclusion Our analysis showed that many patients did not have antimicrobial therapy for infectious diarrhea, which was impacted by the diagnostic test. The increased sensitivity to detect organisms in the GI Panel may account for the increased utilization of definitive antimicrobials in the post-implementation cohort. Disclosures J Kristie Johnson, PhD, D (ABMM), biomerieux: has given presentations/speeches for the company listed above Kimberly C. Claeys, PharmD, PhD, bioMérieux: Advisor/Consultant|bioMérieux: Honoraria

The real‐life positive predictive value of the Biofire FilmArray™ pathogen panel for stool culture organisms is modest

What is Known PCR based gastrointestinal pathogen testing is highly sensitive and specific. PCR based gastrointestinal pathogen testing may be clinically too sensitive.What is New The positive predictive value of the Biofire FilmArray™ pathogen panel for stool culture organisms was modest, ~60% in pediatric patients. None of the multi‐positive GI pathogen panels for stool culture organisms were confirmed by stool culture. Positive, especially multi‐positive Biofire FilmArray™ pathogen panels for stool culture organisms should be carefully considered in the clinical setting.

Hybrid strains of enterotoxigenic/Shiga toxin-producing Escherichia coli, United Kingdom, 2014-2023.

Introduction. Diarrhoeagenic Escherichia coli (DEC) pathotypes are defined by genes located on mobile genetic elements, and more than one definitive pathogenicity gene may be present in the same strain. In August 2022, UK Health Security Agency (UKHSA) surveillance systems detected an outbreak of hybrid Shiga toxin-producing E. coli/enterotoxigenic E. coli (STEC-ETEC) serotype O101:H33 harbouring both Shiga toxin (stx) and heat-stable toxin (st).Gap statement. These hybrid strains of DEC are a public health concern, as they are often associated with enhanced pathogenicity. However, little is known about their epidemiology, clinical significance and associated public health burden.Aim. The aim of this study was to describe the microbiology, epidemiology and genomic analysis of this novel hybrid serotype in the context of the STEC-ETEC strains in the UKHSA archive.Methodology. From 2014 to 2023, STEC isolated from faecal specimens testing positive for STEC by PCR were sequenced on the NextSeq 1000 short read platform and a subset were selected for long read nanopore sequencing. Genomes were analysed to determine serotype, stx subtype, DEC pathogenicity genes and antimicrobial resistance determinants.Results. There were 162 STEC-ETEC strains isolated between 2014 and 2023, of which 117/162 were human clinical isolates and 45 were of food or animal origin. An average of 16 STEC-ETEC strains were identified each year, exhibiting a range of different stx subtypes, the most common profiles being stx2g,st (n=65, 40%) and stx2a,st (n=48, 30%). The most common sequence types were ST329 and ST200 (n=24 each), and the most frequently detected serotype was O187:H28 (n=25). Nine cases of genetically linked STEC-ETEC O101:H33, stx1a,st were detected between 8 August and 21 September 2022. Although the temporal and geographical distribution of the cases was characteristic of a foodborne outbreak, the contaminated vehicle was not identified.Conclusions. Phylogenetic analysis and long-read sequencing of the outbreak strain provided insight into the stepwise acquisition of st and stx and the evolutionary history of STEC-ETEC pathotypes. The integration of epidemiological data and whole-genome sequencing for routine surveillance of gastrointestinal pathogens is key to understanding the emergence of zoonotic hybrid DEC pathotypes and monitoring foodborne threats to public health.

Metagenomics: a new frontier for routine pathology testing of gastrointestinal pathogens

BackgroundAccurate and comprehensive identification of enteropathogens, causing infectious gastroenteritis, is essential for optimal patient treatment and effective isolation processes in health care systems. Traditional diagnostic techniques are well established and optimised in low-cost formats. However, thorough testing for a wider range of causal agents is time consuming and remains limited to a subset of pathogenic organisms. Metagenomic next-generation sequencing (mNGS) allows the identification of all pathogens in a sample in a single test, without a reliance on culture or introduction of target selection bias. This study aims to determine the ability to routinely apply mNGS testing, in comparison to traditional culture or polymerase chain reaction (PCR) based tests, for the identification of causal pathogens for gastrointestinal infections.ResultsThe performance of mNGS, PCR and microscopy, culture and sensitivity (MCS) assays was established using 2,619 prospectively collected faecal samples from patients with symptomology indicative of infectious gastroenteritiss. Commonly experienced pathogens including Aeromonas spp, Campylobacter spp, Salmonella spp and Giardia spp, in single and co-infected patients, were used to establish test outcomes. When testing for these organisms, using the combined result from either or both PCR and MCS testing as the comparator, the mNGS assay had clinically acceptable sensitivity (89.2–100%). Further, the mNGS assay detected 14 additional enteropathogens, that were either not detected or not tested, by initial PCR/MCS testing.ConclusionsThe advantage of mNGS compared to other syndromic testing systems is the broad range of detectable targets and the ability to interrogate samples without clinician informed or assay specific bias. With the development of newer sequencing assays, it is now feasible to test for a wide range of target organisms in a sample using a single mNGS test. Overall, the mNGS based approach enabled pathogen detection that was comparable to conventional diagnostics and was shown to have the potential to be extended for the detection of many pathogens and genes of clinical interest. In conclusion, the mNGS assay offers an easy, sample to answer workflow with rapid detection of enteropathogens and has the potential to improve diagnosis, therapy and infection control precautions.

Antimicrobial activity of selected native Australian Terminalia spp. against gastrointestinal pathogens and potentiation of selected antibiotics

Antimicrobial activity of selected native Australian Terminalia spp. against gastrointestinal pathogens and potentiation of selected antibiotics

Rapid and relaying deleterious effects of a gastrointestinal pathogen, Citrobacter rodentium, on bone, an extra-intestinal organ

Rapid and relaying deleterious effects of a gastrointestinal pathogen, Citrobacter rodentium, on bone, an extra-intestinal organ

The relationship between Giardia lamblia infection with Ghrelin hormone and Trefoil factor 3 in patients in Salah al-Din Governorate

Giardiasis is considered one of the parasitic diseases affecting humans, caused by a flagellate protozoan known as Giardia lamblia. It is a common gastrointestinal pathogen that can lead to various clinical and other complications. Study aimed to diagnose infection with the G. lamblia in children aged (1-12 years) using a direct wet mount, and to determine Giardia lamblia by targeting the TPI gene using PCR, in addition to evaluating the relationship of infection of Giardia lamblia with (ghrelin and TFF3) using ELISA assay. By examining 238 stool samples for children suffering from diarrhea and some intestinal symptoms visiting some hospitals in Salah al-Din Governorate. 34 (14.2%) positive samples were recorded by microscopic examination. 100 fecal samples using the PCR, showed 60 (60%) positive samples for the G. lamblia. The study revealed a highly significant increase in the level of TFF3 a non-significant decrease in the level ghrelin in the serum of patients with infection. Direct microscopic examination of stool samples It has good sensitivity for detecting G. lamblia parasite, and the TPI gene targeted in PCR technology has high sensitivity and specificity for genotyping detection of the parasite.

Efficacy of Molecular Methods for the Diagnosis of Enteropathogenic Microorganisms Associated with Diarrhoea: A Systematic Review.

Diarrhoea has a significant health impact and requires accurate diagnostic approaches, despite the limitations of many existing methods. This review examines various molecular techniques aimed at facilitating the rapid diagnosis of diarrhoeal diseases caused by bacterial, viral and parasitic pathogens. A comprehensive systematic literature review was conducted using six prestigious databases, including WOS, Scopus, Science Direct, Embase, PubMed and LILACS Plus. This rigorous approach allowed the synthesis of reviews on molecular diagnostic techniques for infectious diarrhoeal diseases. This research began with a careful systematic literature review of 2,760 scientific papers published in the last ten years (2014-2024), culminating in the inclusion of 18 studies following rigorous screening and eligibility criteria. In particular, multiplex polymerase chain reaction (PCR), isolation of genomic DNA from stool samples and the Luminex xTAG Gastrointestinal Pathogen Assay emerged as the predominant molecular methods. These techniques demonstrated remarkable consistency in sensitivity, specificity and rapid diagnostic capability, particularly in the context of acute infectious diarrhoeal diseases. They also demonstrated the ability to simultaneously detect and identify multiple pathogens, including bacteria, viruses and parasites. The use of multiplex real-time PCR assays has not only improved the detection rates of enteropathogens, but has also revealed previously unrecognised gaps in the diagnosis of infectious diarrhoea. Our study highlights the importance of using molecular methods for comprehensive diagnosis in terms of sensitivity, specificity and rapid diagnostic capability. This will provide healthcare professionals with timely and accurate diagnostic data, enabling more effective treatment strategies for this public health problem.

Antibacterial, antibiofilm, and gene expression assessment of ajwain (Trachyspermum ammi) essential oil on drug-resistant gastrointestinal pathogens and its combination effect with ampicillin.

Essential oils are natural substances used as therapeutic agents and food preservatives to inhibit harmful microorganisms. This study aimed to assess the synergistic effect of Trachyspermum ammi essential oil and ampicillin on antibiotic-resistant gastrointestinal pathogens, including Escherichia coli, Enterococcus faecalis, Shigella flexneri, and Salmonella serotype Typhimurium. Using gas chromatography-mass spectrometry (GC-MS), the main components of T. ammi essential oil were identified as thymol, gamma terpenes, and cymene. The antibacterial and antibiofilm properties were evaluated by minimum inhibitory concentration (MIC), disk diffusion, and microtiter plate methods, revealing MIC values of 2, 1, 4, and 4mg ml-1 for E. coli, E. faecalis, S. flexneri, and S. Typhimurium, respectively, and inhibition zones between 10 and 14mm. Pathogens were examined for their biofilm-related virulence genes, including aggR, esp, icsA, and fliC, using real-time polymerase chain reaction (RT-PCR) in E. coli, E. faecalis, S. flexneri, and S. Typhimurium, respectively. The methyl thiazole tetrazolium (MTT) assay was used to evaluate the essential oil's effect on the viability of human embryonic kidney 293 (HEK293) cells, which showed cell viability of over 80%. The combination of T. ammi oil and ampicillin demonstrated a synergistic effect, and biofilm formation was inhibited. E. faecalis exhibited the greatest sensitivity, while S. flexneri exhibited the lowest sensitivity.

Spatial and temporal dynamics of the prevalence of resistance genes and gastrointestinal pathogens in stool samples of German deployment returnees.

The exploratory study assessed trends in the abundance of CTX-M-type extended spectrum beta-lactamase (ESBL) and vancomycin-resistance genes vanA and vanB in the stool samples of German soldiers and police officers returning from predominantly tropical deployments next to thecommon diarrheagenic Escherichia (E.) coli pathovars enteropathogenic Escherichia coli (EPEC), enterotoxigenic E. coli (ETEC) and enteroaggregative E. coli (EAEC)) as well as rarely imported Vibrio spp. between 2006 and 2024. Surveillance was performed applying real-time polymerase chain reaction and results were stratified by World Health Organization region of deployment as well as by deployment period. For the latter, the study interval was divided into three pre-COVID-19-pandemic periods, the COVID-19-pandemic period and the post-COVID-19-pandemic period. Averaged prevalences were used as references. In stool samples of 1817 deployed German soldiers and 117police officers, averaged prevalences were 47.9% and 24.8% for the ESBL-type beta-lactamase blaCTX-M, 30.2% and 14.5% for vanB, 9.0% and 17.9% for EPEC, 3.4% and 12.8% for ETEC, 4.0% and 3.4% for EAEC as well as 2.0% and 3.4% for Vibrio spp., respectively. While resistance genes peaked during early deployments, maximum prevalences for enteropathogens were seen later. Theassessment suggested time- and region-dependence of the assessed parameters.

Characterization and Potential Food Applications of Oat Flour and Husks from Differently Colored Genotypes as Novel Nutritional Sources of Bioactive Compounds.

Oats are gluten-free cereals rich in dietary fiber, β-glucans, phenolic acids, flavonoids, carotenoids, vitamin E, and phytosterols. They have been used in traditional medicine for centuries to treat hyperacidity, acute pancreatitis, burns, and skin inflammation. This study assessed the nutritional and phenolic profile of oat flour (OF) and ground oat husks (OHs) from white, brown, and black hulled oat genotypes, as well as the antioxidant and antimicrobial activity of their extracts. The extracts were tested on six strains of gastrointestinal tract pathogens. OF samples had, on average, a high protein content (15.83%), fat content (6.27%), and β-glucan content (4.69%), while OH samples were rich in dietary fiber. OHs had significantly higher average total phenolic compounds compared to OF and had twice as high antioxidant capacity. Ferulic acid was predominant in all samples, followed by p-coumaric, isoferulic, vanillic, and syringic acid. The traditionally prepared OH extracts manifested the best bactericidal activity against Listeria monocytogenes, Escherichia coli, and Staphylococcus haemolyticus, while Salmonella typhimurium was the least sensitive to the bactericidal effect of all the investigated samples. Both OF and powdered OHs have potential applications in the functional food industry and pharmacy due to their bioactive compounds, their biological activity, as well as their overall nutritional profile.

Global Impact of COVID-19 Pandemic on Gastrointestinal Infections: A Scoping Review.

During the COVID-19 pandemic, nonpharmaceutical public health interventions (NPIs) were implemented worldwide to control the spread of severe acute respiratory syndrome coronavirus 2. However, the incidence of other pathogens, including gastrointestinal (GI) pathogens, was also affected. Here, we reviewed studies assessing the impact of NPIs during the COVID-19 pandemic on the incidence of GI infections, particularly foodborne infections. A systems literature search was conducted in May 2023, using Living Evidence on COVID-19 (COAP) and Scopus. Articles were identified and selected through a screening process with inclusion and exclusion criteria based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. Data were extracted from each full-text article included in the review. Parameters included were GI viruses, GI bacteria, NPIs against the COVID-19 pandemic, and the associated impact of NPIs on GI pathogens. A total of 42 articles were included in the review, representing 18 countries. Overall, a larger reduction was observed for viral GI infections compared with bacterial GI infections during the COVID-19 pandemic, particularly for norovirus. For bacterial GI infections, Campylobacter and nontyphoidal Salmonella were the most frequently detected pathogens in the majority of the studies, with the largest reduction observed for Shigella and Shiga toxin-producing Escherichia coli infections. The sharp decrease in GI viral infections in most of the included countries is suggested to be related to the disruption of person-to-person transmission due to several implemented interventions (e.g., social distancing and hand hygiene). GI bacterial pathogens, more commonly transmitted via the foodborne route, were least impacted, and their reduction is associated with closure of food-providing settings and travel restrictions. However, the observed changes appear to be multifactorial; alterations in health-care-seeking behaviors and in routinary diagnostic testing have undeniably played a significant role, affecting national surveillance systems. Therefore, although NPIs likely had a substantial impact on the burden of GI infectious diseases, the extent of the true change cannot be fully assessed.

Positive impact of a diagnostic stewardship intervention on syndromic panel ordering practices and inappropriate C. difficile treatment.

Multiplex polymerase chain reaction (PCR) panels for stool testing may be used to diagnose Clostridioides difficile, which can circumvent more appropriate targeted C. difficile testing, resulting in treatment of incidentally detected colonization. We sought to reduce C. difficile diagnosis via a gastrointestinal pathogen panel (GIPP). Quasi-experimental, pre/post, retrospective cohort study from January 1, 2022, to January 31, 2024. Mayo Clinic Arizona-a single academic medical center and associated clinics. Adult patients receiving C. difficile testing and/or treatment. Preferred C. difficile testing consisted of glutamate dehydrogenase and toxin antigen immunoassay, followed by toxin gene testing for discrepant results. The GIPP contained 22 targets during the baseline period with C. difficile removed during the postintervention period. Surveys were provided to provider and nursing groups, separately, to identify C. difficile ordering practices and knowledge gaps. At baseline, from January 1, 2022, to January 31, 2023, 2,772 GIPPs were completed for 2,307 unique patients (∼7 per day), primarily for outpatients (1,805 of 2,772, 65%). The most common positive target was C. difficile (517 of 1,018, 51%), which resulted in treatment for C. difficile infection in 94.9% (337 of 355) of cases. Following GIPP C. difficile target removal, GIPP orders decreased from 3.23 to 2.7 per 1,000 patient visits (P < .001). Prescribing of C. difficile treatments decreased in the postintervention period in inpatient and outpatient settings. There were no cases of delayed C. difficile diagnosis during the postintervention period. Removing C. difficile from the GIPP resulted in effective diagnostic and antimicrobial stewardship without resulting in delayed diagnoses.

In vitro Cytotoxicity of Selected Medicinal Plant Extracts used for the Management of Gastroenteritis in Northern Namibia, and their Antibacterial Activity against Multidrug-resistant Pathogens

The global challenge of antibiotic resistance among gastrointestinal pathogens is increasing daily. Gastroenteritis is a major health challenge in developing countries and is ranked 8th among the top 10 causes of death in Namibia. While medicinal plants used in Namibia could be the source of medicine for gastroenteritis, there is a gap in knowledge regarding the efficacy and safety of most medicinal plants used in Namibia. The study aimed to evaluate the antibacterial and cytotoxicity of medicinal plants used in Namibia to manage gastroenteritis. Aqueous and methanol extracts were prepared from Lantana camara, Grewia tenax, Corchorus tridens, Albizia anthelmintic, and Terminalia sericea. Agar disc diffusion and resazurin-based microtiter dilution assay were used to determine the antibacterial activity. Antibiogram assay was used to determine the susceptibility of gastrointestinal pathogens to 11 clinically used antibiotics. Normal mouse embryo fibroblast cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay were used for the cytotoxicity test. A 70% multidrug resistance to ampicillin, cephalosporin, sulphamethoxazole, erythromycin, penicillin, vancomycin, and ampicillin was observed among clinical isolates of Salmonella and Escherichia coli. Meanwhile, L. camara methanol seed extracts showed potent antibacterial activity against clinical strains of E. coli and Salmonella spp. (20.67 ± 1.53 and 21.67 ± 0.58 mm, respectively), with MICs between 31.25 and 62.5 µg/mL. The IC50 of all extracts was ≥65.85.00 ± 0.58 µg/mL. The study showed that methanol extracts of L. camara, C. tridens, and T. sericea have potent antibacterial activity against multidrug-resistant clinical Salmonella and E. coli. Moreover, methanol extracts did not show significant toxicity to NIH/3T3 cells.

Comparison of QIAstat-Dx and BioFire FilmArray Gastrointestinal Panels in a Pediatric Population.

Accurate laboratory diagnosis of gastroenteritis is important to ensure that patients receive appropriate treatment and proper isolation precautions. This study evaluated the performance of the QIAGEN QIAstat-Dx gastrointestinal panel (QGP) in comparison to the bioMerieux BioFire FilmArray gastrointestinal panel (BGP) for the detection of gastrointestinal pathogens in 110 pediatric patients being evaluated for gastroenteritis at our hospital. We compared 23 different bacterial, viral, and parasite enteropathogens detected by the QGP against the BGP. The overall positive percent agreement (PPA) for all compared targets was 96.2% and the overall negative percent agreement (NPA) for all compared targets was 99.7%. Our study shows that QIAstat-Dx QGP provides comparable results to the BioFire BGP in our pediatric population. Additionally, the PCR cycle threshold (Ct) value reported by the QGP is potentially a helpful tool in estimating the load of the detected pathogen in stool samples.