Treatment Of CDI Research Articles

Fecal microbiota composition is a better predictor of recurrent Clostridioides difficile infection than clinical factors in a prospective, multicentre cohort study

IntroductionClostridioides difficile infection (CDI) is the most common cause of antibiotic-associated diarrhoea. Fidaxomicin and fecal microbiota transplantation (FMT) are effective, but expensive therapies to treat recurrent CDI (reCDI). Our objective was to develop a prediction model for reCDI based on the gut microbiota composition and clinical characteristics, to identify patients who could benefit from early treatment with fidaxomicin or FMT.MethodsMulticentre, prospective, observational study in adult patients diagnosed with a primary episode of CDI. Fecal samples and clinical data were collected prior to, and after 5 days of CDI treatment. Follow-up duration was 8 weeks. Microbiota composition was analysed by IS-pro, a bacterial profiling technique based on phylum- and species-specific differences in the 16–23 S interspace regions of ribosomal DNA. Bayesian additive regression trees (BART) and adaptive group-regularized logistic ridge regression (AGRR) were used to construct prediction models for reCDI.Results209 patients were included, of which 25% developed reCDI. Variables related to microbiota composition provided better prediction of reCDI and were preferentially selected over clinical factors in joint prediction models. Bacteroidetes abundance and diversity after start of CDI treatment, and the increase in Proteobacteria diversity relative to baseline, were the most robust predictors of reCDI. The sensitivity and specificity of a BART model including these factors were 95% and 78%, but these dropped to 67% and 62% in out-of-sample prediction.ConclusionEarly microbiota response to CDI treatment is a better predictor of reCDI than clinical prognostic factors, but not yet sufficient enough to predict reCDI in daily practice.

Real-world Effectiveness of Fecal Microbiota Transplantation for First or Second Clostridioides difficile Infection

Background and aimsClostridioides difficile infection (CDI) is associated with high mortality. Fecal microbiota transplantation (FMT) is an established treatment for recurrent CDI, but its use for first or second CDI remains experimental. We aimed to investigate the effectiveness of FMT for first or second CDI in a real-world clinical setting. MethodsThis multi-site Danish cohort study included patients with first or second CDI treated with FMT from June 2019 to February 2023. The primary outcome was cure of C. difficile-associated diarrhea (CDAD) eight weeks after the last FMT treatment. Secondary outcomes included CDAD cure one and eight weeks after the first FMT treatment and 90-day mortality following positive C. difficile test. ResultsWe included 467 patients, with 187 (40%) having their first CDI. The median patient age was 73 years (interquartile range (IQR) 58-82 years). Notably, 167 (36%) had antibiotic-refractory CDI, 262 (56%) had severe CDI, and 89 (19%) suffered from fulminant CDI. Following the first FMT treatment, cure of CDAD was achieved in 353 patients (76%, 95% confidence interval (CI) 71-79%) at week one. At week eight, 255 patients (55%, 95% CI 50-59%) maintained sustained effect. In patients without initial effect, repeated FMT treatments led to an overall cure of CDAD in 367 patients (79%, 95% CI 75-82%). The 90-day mortality was 10% (95% CI 8-14%). ConclusionRepeated FMT treatments demonstrate high effectiveness in managing patients with first or second CDI. Forwarding FMT in CDI treatment guidelines could improve patient survival.

Fecal microbiota transplantation stimulates type 2 and tolerogenic immune responses in a mouse model

ObjectivesClostridioides difficile infection (CDI) is the leading hospital-acquired infection in North America. While previous work on fecal microbiota transplantation (FMT), a highly effective treatment for CDI, has focused on colonization resistance mounted against C. difficile by FMT-delivered commensals, the effects of FMT on host gene expression are relatively unexplored. This study aims to identify transcriptional changes associated with FMT, particularly changes associated with protective immune responses. MethodsGene expression was assessed on day 2 and day 7 after FMT in mice after antibiotic-induced dysbiosis. Flow cytometry was also performed on colon and mesenteric lymph nodes at day 7 to investigate changes in immune cell populations. ResultsFMT administration after antibiotic-induced dysbiosis successfully restored microbial alpha diversity to levels of donor mice by day 7 post-FMT. Bulk RNA sequencing of cecal tissue at day 2 identified immune genes, including both pro-inflammatory and Type 2 immune pathways as upregulated after FMT. RNA sequencing was repeated on day 7 post-FMT, and expression of these immune genes was decreased along with upregulation of genes associated with restoration of intestinal homeostasis. Immunoprofiling on day 7 identified increased colonic CD45+ immune cells that exhibited dampened Type 1 and heightened regulatory and Type 2 responses. These include an increased abundance of eosinophils, alternatively activated macrophages, Th2, and T regulatory cell populations. ConclusionThese results highlight the impact of FMT on host gene expression, providing evidence that FMT restores intestinal homeostasis after antibiotic treatment and facilitates tolerogenic and Type 2 immune responses.

Systemic neutrophil degranulation and emergency granulopoiesis in patients with Clostridioides difficile infection

ObjectivesClostridioides difficile infection (CDI) is characterized by neutrophilia in blood, with a high leukocyte count accompanying severe infection. In this study, we characterized peripheral blood neutrophil activation and maturity in CDI by (i) developing a method to phenotype stored neutrophils for disease-related developmental alterations and (ii) assessing neutrophil-associated biomarkers. MethodsWe stored fixed leukocytes from blood collected within 24 h of diagnosis from a cohort of hospitalized patients with acute CDI. Additional study cohorts included recurrent CDI patients at time of and two months after FMT therapy and a control healthy cohort. We assessed levels of neutrophil surface markers CD66b, CD11b, CD16 and CD10 by flow cytometry. Plasma neutrophil elastase and lipocalin-2 were measured using ELISA, while G-CSF, GM-CSF and cytokines were measured using O-link Proteomic technology. ResultsCD66b+ neutrophil abundance assessed by flow cytometry correlated well with complete blood counts, establishing that neutrophils in stored blood are sufficiently well-preserved for phenotyping by flow cytometry. Neutrophil abundance was significantly increased in CDI patients compared to healthy controls. Emergency granulopoiesis in acute CDI patients was evidenced by lower neutrophil surface expression of CD10, CD11b and CD16. CD10+ staining of neutrophils started to recover within 3–7 days of CDI treatment. Neutrophil activation and degranulation were higher in acute CDI as assessed by plasma neutrophil elastase and lipocalin-2. Biomarker levels in immunocompetent subjects were associated with recurrence and fatal outcomes. ConclusionsNeutrophil activation and emergency granulopoiesis characterize the early immune response in acute CDI, with plasma degranulation biomarkers predictive of disease severity.

The anti-inflammatory and anti-apoptotic effects of Achillea millefolium L. extracts on Clostridioides difficile ribotype 001 in human intestinal epithelial cells

BackgroundClostridioides difficile infection (CDI) is one of the most common health care-acquired infections. The dramatic increase in antimicrobial resistance of C. difficile isolates has led to growing demand to seek new alternative medicines against CDI. Achillea millefolium L. extracts exhibit strong biological activity to be considered as potential therapeutic agents. In this work, the inhibitory effects of A. millefolium, its decoction (DEC) and ethanol (ETOH) extracts, were investigated on the growth of C. difficile RT001 and its toxigenic cell-free supernatant (Tox-S) induced inflammation and apoptosis.MethodsPhytochemical analysis of extracts was performed by HPLC and GC analysis. The antimicrobial properties of extracts were evaluated against C. difficile RT001. Cell viability and cytotoxicity of Caco-2 and Vero cells treated with various concentrations of extracts and Tox-S were examined by MTT assay and microscopy, respectively. Anti-inflammatory and anti-apoptotic effects of extracts were assessed in Tox-S stimulated Caco-2 cells by RT-qPCR.ResultsAnalysis of the phytochemical profile of extracts revealed that the main component identified in both extracts was chlorogenic acid. Both extracts displayed significant antimicrobial activity against C. difficile RT001. Moreover, both extracts at concentration 50 µg/mL had no significant effect on cell viability compared to untreated cells. Pre-treatment of cells with extracts (50 µg/mL) significantly reduced the percentage of Vero cells rounding induced by Tox-S. Also, both pre-treatment and co-treatment of Tox-S stimulated Caco-2 cells with extracts significantly downregulated the gene expression level of IL-8, IL-1β, TNF-α, TGF-β, iNOS, Bax, caspase-9 and caspase-3 and upregulated the expression level of Bcl-2.ConclusionThe results of the present study for the first time demonstrate the antimicrobial activity and protective effects of A. millefolium extracts on inflammatory response and apoptosis induced by Tox-S from C. difficile RT001 clinical strain in vitro. Further research is needed to evaluate the potential application of A. millefolium extracts as supplementary medicine for CDI prevention and treatment in clinical setting.

Enhancing U(VI) removal by using biomass-derived hierarchical porous carbon/α-MnO2 nano fiber composites as high hybrid capacitance electrodes for capacitive deionization

The radioactive pollution caused by uranium containing wastewater generated during the nuclear fuel cycle seriously threatens human health and environmental safety. The electrosorption (or capacitive deionization, CDI) separation of U(VI) from wastewater has the advantages of high efficiency, low energy consumption, convenient operation, and no secondary pollution, making it a promising new separation technology. By combining double layer capacitive materials with pseudo capacitive materials, the specific capacitance and ion storage capacity of the composites can be significantly improved, thereby improving the electrosorption performance. This work used natural biomass as raw material to prepare hierarchical porous biocarbon through high-temperature pyrolysis and chemical activation, and then it was incorporated with hydrothermally synthesized α-MnO2 nanofibers to obtain novel composites (BC/α-MnO2) with high hybrid capacitance for U(VI) removal in CDI. The electrochemical characteristics of the composites and their electrosorption performances for U (VI) were respectively investigated in a three electrode system and a CDI device. The results suggested that BC/α-MnO2 exhibited an ideal capacitive behavior, and theoretical calculations indicated the synergistic effect of capacitive and diffusion control processes on ion storage. Among different BC/α-MnO2 electrodes, BC/α-MnO2-2 had the highest specific capacitance (130.48 F/g) and also the highest adsorption capacity for U (VI) (280.20 mg/g at 0.9 V and pH 4.0). The isotherms and kinetics of U (VI) electrosorption were consistent with the Langmuir and PFO models, respectively. The electrosorption mechanism was mainly related to the contribution of pseudocapacitance and EDL adsorption. Overall, BC/α-MnO2-2 exhibited ideal electrochemical properties and excellent electrsorption performance for U (VI) (high electrosorption capacity, fast kinetic rate, and good cycling stability), facile fabrication and environmentally friendly, and thus it has promising application in CDI treatment of radioactive wastewater.

S207 Predictive Machine Learning Models for Recurrent C. difficile Infection in Inflammatory Bowel Disease Patients Based on First-Episode CDI Treatment

S207 Predictive Machine Learning Models for Recurrent C. difficile Infection in Inflammatory Bowel Disease Patients Based on First-Episode CDI Treatment

Budesonide, an anti-inflammatory drug, exacerbate clostridioides difficile colitis in mice

Background and aimsClostridioides difficile infection (CDI) induces intense acute inflammatory responses through toxin release. A combination of antibiotic and anti-inflammatory agents is sometimes recommended in severe, non-responsive cases, although clinical trials have been inconclusive, raising concerns about potential complications. This study aims to investigate the effect of budesonide and mesalamine in the treatment of CDI in a murine model, by evaluating the combination of fidaxomicin and these anti-inflammatory drugs. MethodC57BL/6 J female mice pretreated with an antimicrobial mixture were challenged with C. difficile VPI 10463 or culture media by gavage. After the challenge, mice received placebo, fidaxomicin alone (20 mg/kg), or fidaxomicin combined with mesalamine (200, 400 mg/kg) or budesonide (0.2, 1, 10 mg/kg) for 5 days. The mice were monitored for 7 days with weight and survival. Colon and cecum tissues were harvested for histological assessment. ResultsCDI of mice caused 80% mortality. Fidaxomicin completely protected against CDI in all parameters (weight, survival and pathscores). Mortality rates were up to 90%, 70% in budesonide(10 mg/kg) and mesalamine (400 mg/kg) treatment group, respectively. Budesonide (0.02,0.1 and 1 mg/kg) adjunction to fidaxomicin worsened the disease outcome according to all tested parameters. While mesalamine in combination with fidaxomicin (200, 400 mg/kg) did not lead to any deaths during CDI treatment, it did not provide additional benefits. ConclusionsAnti-inflammatory drugs including corticosteroid therapy may worsen the incidence and severity of CDI in this mouse model. These studies may have important clinical implications for understanding the role of anti-inflammatory/ corticosteroid therapy in CDI and inflammatory bowel disease management.

The therapeutic effect of oral desmopressin lyophilisate formulation in children with central diabetes insipidus.

We aimed to assess the efficacy of oral use of oral desamino-D-arginine-8-vasopressin lyophilisate (OLD) in children with central diabetes insipidus (CDI). Clinical, laboratory, and imaging characteristics of twenty-five children with CDI treated with OLD were evaluated. Fourteen boys and eleven girls with a mean age of 52.37 months were evaluated. These children (mean weight and height at admission, 26.81±14.8 kg vs. 92.52±30 cm) presented with failure to thrive, irritability, prolonged fever, polyuria and hypernatremia (mean sodium level, 143.12±8.6 mEq/L). At the time of hypernatremia, mean serum and urine osmolality were 298.2±18 mOsm/kg and 160.20±8.7 mOsm/kg, respectively. ADH levels were undetectable (<0.5 pmol/L) at admission in all cases. Oral administration of desmopressin lyophilisate (120 µg/tablet) was initiated at a dose of 5 μg/kg/day in two divided doses together with controlled water intake to avoid hyponatremia. Serum sodium levels normalised in a mean durationof 15.2±16.4 h with a mean decline rate of 0.12±0.04 mEq/L/h. Nine children needed rehospitalization because of hypernatremia due to non-compliance. Four episode of hyponatremia was observed. Weight gain and growth were normal during the mean follow-up duration of 37.79±48.2 months. Administration of OLD was practical and safe in the treatment of CDI in children with CNS malformations in this small retrospective series.

Biocarbon/polyaniline nanofiber electrodes with high hybrid capacitance and hierarchical porous structure for U(VI) electrosorption

The removal of U(VI) from nuclear effluents is significant for uranium resource recovery and environmental safety. Herein, polyaniline (PANI) was electrodeposited on porous biocarbon (cotton derived carbon, CC) to fabricate a high-performance composite electrode (CC/PANI) for U(VI) electrosorption. The CC/PANI electrode showed high specific capacitance and excellent cyclic stability, it also exhibited capacitive control characteristics for which the capacitance contribution has been quantified. The electrosorption results indicate that CC/PANI-2 has the highest specific capacitance among various CC/PANI electrodes, and also exhibits the highest electrosorption capacity for U(VI), reaching a maximum value of 282.2 mg/g at pH 4.0 and 0.9 V. The modeling results of electrosorption isotherms and kinetics for U(VI) indicated the good simulation by Langmuir and PFO models, respectively. The excellent electrosorption performance of CC/PANI-2 for U (VI) is attributed to its high hybrid capacitance, good conductivity, and improved hydrophilicity. The electrosorption mechanism for U(VI) removal is mainly ascribed to EDL and pseudocapacitive electrosorption, with possible contribution from U(VI) coordination by N atoms of CC/PANI. This work provides the strategy of incorporating PANI with biocarbon to fabricate a novel electrode for the efficient CDI treatment of radioactive nuclear wastewater.

Comparison between Vancomycin and Fidaxomicin in treatment ofCDI

Clostridium difficile infection (CDI) has become more and more prevalent worldwide, requiring more attention frompeople to treat this infection. In this work, the epidemiology of Clostridium difficile infection in the world and China isdemonstrated, which can contribute to a better understanding of the way of infection and patients’ conditions of CDI andlook for possible methods or policies to help prevent the spread of this disease. On the other hand, there is a growingdemand for more reliable and efficient antibiotic treatments for CDI, of which fidaxomicin and vancomycin are regardedas the most common. This work aims to compare the chemical structures, action mechanisms, and cost-effectiveness offidaxomicin and vancomycin to assist choices between two antibiotics for CDI patients and healthcare workers.

Polymetallic Clusters in Capacitive Deionization

Research and development of water purification technology can effectively alleviate the impact of water shortage. Capacitive deionization technology (CDI) is a novel water treatment technology, by applying low voltage, ions in solution are absorbed by electrodes to form double electric layers to remove pollutants in water. Electrode material is the main factor affecting the effect of CDI treatment. At present, the traditional CDI electrodes mainly focus on the research of carbon materials and carbon-based composites materials. However, their low effective specific surface area, complex preparation process and high resistance limit their application in practical wastewater treatment. Mixed metal oxides have become a new hotspot in the research and application of CDI electrode materials due to their excellent electrochemical properties, such as high reactivity, large specific capacitance and strong conductivity. However, there are few articles on its research and application in CDI. Therefore, this paper reviews the latest research progress, existing problems and application development of mixed metal oxide electrodes and their composite electrodes in the context of the types of polymetallic oxides.

Fecal microbiota transplantation for treatment of refractory or recurrent Clostridioides difficile infection in Taiwan: a cost-effectiveness analysis.

Compared to antibiotic treatment, fecal microbiota transplantation (FMT) is a more effective treatment for refractory or recurrent CDI (rCDI). Patients with inflammatory bowel disease (IBD) have a higher incidence of CDI and worse outcomes. There has been no study from Asia to evaluate the cost-effectiveness of FMT for overall rCDI patients and rCDI patients with IBD. We applied a Markov model with deterministic and probabilistic sensitivity analyses to evaluate the cost and effectiveness of different treatments for rCDI patients with a time horizon of 1 year from the payer's perspective. We compared the cost and clinical outcomes of FMT through colonoscopy to two antibiotics (vancomycin and fidaxomicin) using data from Chang Gung Memorial Hospital, Taoyuan, Taiwan. Compared to vancomycin, FMT was cost-effective in overall rCDI patients as well as IBD patients with rCDI [USD 39356 (NT$1,101,971.98)/quality-adjusted life year (QALY) gained in overall patients; USD65490 (NT$1,833,719.14)/QALY gained in IBD patients]. Compared to fidaxomicin, FMT was only cost-effective in overall rCDI patients [USD20255 (NT$567,133.45)/QALY gained] but slightly increased QALY (0.0018 QALY gained) in IBD patients with rCDI. FMT is cost-effective, compared to vancomycin or fidaxomicin, for the treatment of rCDI in most scenarios from the payers' perspective in Taiwan.

924. Reducing Rates of Hospital Acquired Clostridium Difficile Infection by Switching to Two-Step Testing

Abstract Background Clostridium difficile infection (CDI) tests have various degrees of sensitivity, making diagnosis challenging. Polymerase chain reaction (PCR) positive tests in colonized patients can impact rates of hospital-acquired CDI (HACDI). A negative toxin A/B enzyme immunoassay (EIA) as a second step can help determine colonization but is not as sensitive. We aimed to study the impact of a two-step testing strategy on rates of HACDI and CDI treatment outcomes. Methods Two-step testing consisted of C. difficle DNA PCR, which if positive, was followed by toxin A/B EIA (Figure 1). We conducted a retrospective study in a 359-bed hospital from March 2020 to July 2021. Patients with positive PCR and negative EIA results were included and further classified based on CDI treatment status. The primary outcome was the number of HACDI cases avoided. Secondary outcomes included location at the time of testing, symptoms, leukocytosis, discharge disposition and readmission. Results Ninety-six patients were included. Sixty-five patients (68%) were treated while 31 (32%) were not. HACDI was avoided in 18 cases (18.8%). There were more HACDI avoided in the non-treated group compared to the treated group (32.3% vs 12.3%; p=0.026). Most non-treated patients were tested on medical-surgical units (77.4%), whereas 49.2 % of the treated patients were tested in more acute areas such as emergency or intensive care. Treated patients were more likely to have leukocytosis and/or fever (66.2%) compared to non-treated patients (29%; p= 0.0009), while there was no difference in abdominal pain, diarrhea, bloody stool, or constipation (Table 1). Most patients had an abdominal CT scan (70.8%). Of those that had a CT, colitis was found in 48.5%. Patients in the treated group were more likely to have had a CT completed that showed colitis vs the non-treated patients (43.1% vs 16.1%; p&amp;lt; 0.011). Finally, compared to the non-treated patients, treatment did not affect home disposition on discharge or 30-day readmission rate (80% vs 71%, P=0.436) and (25 % vs 29%, P= 0.63) respectively. Symptoms Associated with C. difficile infection. Schematic of C. difficile test interpretation. Conclusion CDI two-step testing led to decreased HACDI rates without affecting discharge disposition or readmission rates in patients with PCR positive and toxin EIA negative results regardless of treatment status. Disclosures All Authors: No reported disclosures.

379. A budget impact analysis of bezlotoxumab for the management of recurrent Clostridioides difficile infection in the United States

Abstract Background Clostridioides difficile infection (CDI) is one of the most frequently reported healthcare-associated infections in the US with almost half a million cases reported annually. The most recent IDSA guidelines recommend use of bezlotoxumab (BEZ) in addition to standard of care (SoC) antibiotics for patients who have a CDI episode and at least one risk factor for recurrence. The objective of this study was to estimate the budget impact of the use of BEZ+SoC vs SoC alone from a hospital perspective in the US. Methods A decision analytic model was developed, considering treatment of the index recurrent CDI (rCDI) episode and subsequent recurrences (a maximum of two) over a one-year period, in patients who had at least one risk factor of rCDI. Two scenarios were compared: one with BEZ+SoC, and one with SoC alone. The analysis included costs and payments of medications and the cost of managing rCDI, as well as proportion of BEZ utilization across management settings (with the assumption of 50% inpatient and 50% outpatient). Parameters were retrieved from published sources and expert opinion was sought. The budget impact was calculated as the difference in revenue (difference in payments and costs) between scenarios. One-way sensitivity analyses were performed on key parameters. Costs were expressed in 2021/2 US dollars. Results Among 10,000 hypothetical hospitalizations, treatment with BEZ+SoC of at-risk patients instead of SoC alone in the base case analysis was estimated to result in a potential savings of $53,361 at the hospital level, $497 per treated rCDI patient, and $5.34 per admitted patient. The additional cost of BEZ was offset by the lower rCDI rate in those treated with BEZ. Sensitivity analyses demonstrated the robustness of results. Conclusion For patients with CDI and at risk for recurrence, treatment with BEZ+SoC is cost saving from a hospital perspective. Broader benefits of BEZ+SoC should be considered by healthcare stakeholders and policy makers when making decisions about formulary inclusion and adoption. Disclosures Yiling Jiang, MSc, MSD (UK) Ltd.: Employment|MSD (UK) Ltd.: Stocks/Bonds Abhishek Deshpande, MD, PhD, Clorox: Grant/Research Support|Merck: Advisor/Consultant|Seres Therapeutics: Grant/Research Support Qinghua Li, PhD, Merck &amp; Co., Inc.: employee Lisa Siegartel, MPH, Merck &amp; Co., Inc.: Employee|Merck &amp; Co., Inc.: Ownership Interest Fakhar Siddiqui, MD, MBA, Merck &amp; Co., Inc.: employee|Merck &amp; Co., Inc.: Stocks/Bonds Engels N. Obi, PhD, Merck &amp; Co., Inc.: Employee|Merck &amp; Co., Inc.: Stocks/Bonds.

Detection of Plasmid-Mediated Resistance to Metronidazole in Clostridioides difficile from River Water

ABSTRACTClostridioides difficile is one of the most important human pathogens. The identification of its possible sources is important for the understanding of C. difficile infection (CDI) epidemiology. A total of 16 water samples from wastewater and surface water in South Moravia in the Czech Republic and 82 samples of fish and gulls were collected between May and July 2019. C. difficile isolates were cultured by direct plating and after enrichment on chromogenic media. Susceptibility testing to eight antimicrobials was performed by Etest. C. difficile isolates were characterized by ribotyping, multilocus sequence typing, multilocus tandem repeats analysis, and toxin gene detection. Samples from fish and gulls were C. difficile negative; a total of 15 C. difficile isolates from 8 out of 16 water samples were cultured (6 out of 14 surface water samples yielded 6 isolates, and 2 out of 2 wastewater samples yielded 9 isolates). Direct plating was culture positive in 6 out of 16 samples (12 isolates), and enrichment culture was positive in an additional 2 out of 16 samples (3 isolates). Twelve different ribotyping profiles and 14 sequence types of clades 1, 4, and 5 were identified. Five isolates did not carry genes for toxins, and eight isolates carried genes for toxins A and B; the remaining two isolates (RT078) carried the genes for toxins A, B, and binary. All C. difficile isolates were susceptible to amoxicillin, moxifloxacin, tetracycline, and vancomycin and resistant to ciprofloxacin. A high level of erythromycin resistance (>256 mg/L) was detected in eight isolates. Clindamycin resistance was found in 14 isolates, 6 of which showed a high level of resistance (>256 mg/L) and carried ermB. Surprisingly, one isolate (RT010, ST15) showed resistance to metronidazole (12 mg/L) with the presence of the plasmid pCD-METRO. In conclusion, a diverse spectrum of C. difficile strains was found in wastewater and surface water. A recently discovered plasmid-bound resistance to metronidazole was detected in C. difficile from the surface water sample.IMPORTANCE The combination of direct plating and culture after enrichment was used in order to gain a spectrum of C. difficile ribotypes present in the water samples. Toxigenic C. difficile ribotypes detected in surface water and in wastewater treatment plants overlapped with those derived from patients with CDI and/or animals. Importantly, a recently discovered plasmid-mediated resistance to metronidazole, a drug used for the treatment of CDI, was detected in C. difficile from river water.

Application of consolidated framework for implementation research to improve Clostridioides difficile infection management in district hospitals

BackgroundClostridioides difficile infection (CDI) contributes the global threats of drug resistant infections, healthcare acquired infections and antimicrobial resistance. Yet CDI knowledge among healthcare providers in low-resource settings is limited and CDI testing, treatment, and infection prevention measures are often delayed.Objectives: to develop a CDI intervention informed by the local context within South African public district level hospitals, and analyze the CDI intervention and implementation process. MethodsA CDI checklist intervention was designed and implemented at three district level hospitals in the Western Cape, South Africa that volunteered to participate. Data collection included a retrospective medical records review of patients hospitalized with C. difficile test orders during the 90 days post-implementation. Patient outcomes and checklist components (e.g. antibiotics) were collected. Qualitative interviews (n = 14) and focus groups (n = 6) were conducted with healthcare providers on-site. The Consolidated Framework for Implementation Research (CFIR) and the Framework for Reporting Adaptations and Modifications to Evidence-based Implementation Strategies (FRAME-IS) were applied to collected data and observations in order to identify drivers and barriers to implementation and understand differences in uptake. ResultsOne of the three hospitals displayed high intervention uptake. Highly relevant CFIR constructs linked to intervention uptake included tension for change, strong peer intervention champions, champions in influential leadership positions, and the intervention's simplicity (CFIR construct: complexity). Tension for change, a recognized need to improve CDI identification and treatment, at the high uptake hospital was also supported by an academic partnership for antimicrobial stewardship. ConclusionsThis research provides a straight-forward health systems strengthening intervention for CDI that is both needed and uncomplicated, in an understudied low resource setting. Intervention uptake was highest in the hospital with tension for change, influential champions, and existing academic partnerships. Implementation in settings with fewer academic connections requires further testing of collaborative implementation strategies and proactive adaptations.

Intestine epithelial cell-derived extracellular vesicles alleviate inflammation induced by Clostridioides difficile TcdB through the activity of TGF-β1

BackgroundClostridioides difficile infection (CDI) has been primarily associated with the toxin B (TcdB), one of the three known protein toxins secreted by C. difficile, which can activate the intestinal immune system and lead to pathological damage. Even though the biological functions of intestine epithelial cell-derived extracellular vesicles (I-Evs) have been well documented, the role of I-Evs in the process of CDI is still unknown.ObjectivesThe protective effect of I-Evs against C. difficile TcdB was investigated both in cultured murine colon carcinoma MC38 cells and a mouse model used in this study.ResultsMouse I-Evs with mean diameter ranging from 100 to 200 nm and a density of 1.09–1.17 g/mL were obtained and confirmed containing the Ev-associated specific surface markers CD63 and TSG101 as well as high level of TGF-β1. In MC38 cells, I-Evs were able to decrease the gene expression of IL-6, TNF-α, IL-1β, and IL-22 induced by C. difficile TcdB, but to increase both the gene expression and protein levels of TGF-β1. I-Evs treatment via intraperitoneal administration alleviates C. difficile TcdB-induced local colon inflammation in mice and increased their survival rate from 50% up to 80%. Furthermore, I-Evs induced an increase in the proportion of CD4+Foxp3+Tregs in vitro and in vivo through a TGF-β1-dependent mechanism by activating the TGF-β1 pathway and prompting phosphorylation of the downstream proteins Smad 2/3.ConclusionFor the first time, our study demonstrated that I-Evs originated from intestine epithelial cells can alleviate inflammation induced by C. difficile TcdB both in vitro and in vivo. Therefore, I-Evs might be potentially a novel endogenous candidate for effective treatment of CDI.

Abstract 1811: Dithiazanine Iodide suppresses mitochondrial function to strongly inhibit pancreatic ductal adenocarcinoma growth in-vitro and in-vivo, producing a marked increase in survival

Abstract Pancreatic ductal adenocarcinoma (PDAC) is an aggressive recalcitrant cancer with a uniquely austere tumor microenvironment (TME). It is hypovascularized, hypoxic, and poor in nutrients. These features, which are critical due to the increased energetic demand in continuously replicating cancer cells, drive metabolic reprograming to support the continued activity. Thus leading to a vulnerability in the form of energy restriction - a vulnerability further exacerbated by the nutrient-poor pancreatic cancer TME. We have recently shown mitochondrial inhibition to have great potential in in-vitro inhibition of PDAC cells. Since repurposing of FDA-approved drugs holds great promise in terms of faster and safer drug development, we selected to investigate the effect of mitochondrial inhibition on pancreatic cancer cells through assessment of the previously FDA-approved antimicrobial Dithiazanine Iodide (CDI). CDI is a fluorescent, orally bioavailable, small molecule. In-vitro, it has been previously shown to preferentially localize to the mitochondria, bind proteins and nucleic acids, and have a yet to be discerned inhibitory effect on the electron transport chain. We demonstrated CDI had low IC50s (30-300 nM) in multiple PDAC and other GI cancer cell lines. In an agnostic, unbiased manner, we assessed metabolomic and transcriptomic perturbations caused by CDI. These revealed a profound 92% decrease in the abundance of mitochondrial-encoded transcripts (P&amp;lt;0.05), decreased mitochondrial beta-oxidation, and a reduction in the ATP/ADP ratio. We have therefore hypothesized that the anti-cancer effects of CDI may be related to disruption of mitochondrial processes and we proceeded to characterize its mechanism of action. CDI treatment reduced protein expression of electron transport chain complexes I, II, III, and IV. Treatment with CDI in hypoglycemic conditions resulted in a 3-4 fold increase in sensitivity (P&amp;lt;0.05) and ATP quantification showed a marked &amp;gt;90% decrease in cellular ATP (P&amp;lt;0.05). Furthermore, mitochondria-depleted PDAC cell lines were 4-fold more resistant to CDI treatment (P&amp;lt;0.05). In-vivo, oral CDI treatment resulted in a 2-fold decrease in mouse xenograft tumor growth compared to gemcitabine treatment. RNA-sequencing from the in-vivo samples showed a 60% reduction in the abundance of mitochondrial-encoded transcripts (P&amp;lt;0.05). Examination of the mitochondrial sequences revealed the existence of putative G-Quadruplex sequences. Fluorescence shift and stop-PCR assays confirmed CDI to be a G-Quadruplex binder of mitochondrial sequences. Citation Format: Avinoam Nevler, Christopher W. Schultz, Aditi Jain, Saed Khalilieh, Grace McCarthy, Harish Lavu, Wilbur Bowne, Charles J. Yeo, Jonathan R. Brody. Dithiazanine Iodide suppresses mitochondrial function to strongly inhibit pancreatic ductal adenocarcinoma growth in-vitro and in-vivo, producing a marked increase in survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1811.

Mortality, healthcare resource utilization, and cost among Medicare beneficiaries with Clostridioides difficile infection with and without sepsis.

Objective:To describe mortality, healthcare resource utilization (HRU), and costs among Medicare beneficiaries with primary Clostridioides difficile infection (pCDI) or recurrent CDI (rCDI), with and without sepsis.Methods:We conducted a retrospective observational study of 100% Medicare Fee-for-Service claims from adults aged ⩾ 65 years with ⩾1 CDI episode between 1 January 2009 and 31 December 2017. Patients were continuously enrolled in Medicare Parts A/B/D 12 months before and up to 12 months after pCDI. ICD-9/10 codes defined CDI using ⩾1 inpatient claim, or ⩾1 outpatient claim plus ⩾1 claim for CDI treatment. The pCDI episode ended after 14 days without a CDI claim. rCDI episodes started within 8 weeks from the end of a previous CDI episode. ICD-9/10 codes identified all-cause sepsis over 12 month follow-up.Results:Of 497,489 CDI patients, 41.0% (N = 203,888) had sepsis; 57.7% with sepsis died versus 32.4% without sepsis. Among patients with pCDI only (N = 345,893) or ⩾1 rCDI (N = 151,596), 39.2% and 45.1% suffered sepsis, respectively. All-cause hospitalizations were frequent for all cohorts (range: 81–99%). Among patients who died, those with sepsis versus without had more-frequent intensive care unit (ICU) use (pCDI: 29% versus 15%; rCDI: 65% versus 34%), longer hospital stays (pCDI: 12 versus 10 days; rCDI: 12 versus 9 days), and higher per-patient-per-month costs (pCDI: $34,841 versus $22,753; rCDI: $42,269 versus $25,047). In both cohorts, sepsis patients who survived had higher total costs and all-cause HRU than those without sepsis. All p < 0.001 above.Conclusions:Sepsis was common among Medicare beneficiaries with CDI. CDI patients with sepsis, especially after an rCDI, experienced higher mortality, HRU, and costs compared with those without sepsis.