Nosocomial Diarrhea Research Articles

The current riboswitch landscape in Clostridioides difficile.

Riboswitches are 5' RNA regulatory elements that are capable of binding to various ligands, such as small metabolites, ions and tRNAs, leading to conformational changes and affecting gene transcription or translation. They are widespread in bacteria and frequently control genes that are essential for the survival or virulence of major pathogens. As a result, they represent promising targets for the development of new antimicrobial treatments. Clostridioides difficile, a leading cause of antibiotic-associated nosocomial diarrhoea in adults, possesses numerous riboswitches in its genome. Accumulating knowledge of riboswitch-based regulatory mechanisms provides insights into the potential therapeutic targets for treating C. difficile infections. This review offers an in-depth examination of the current state of knowledge regarding riboswitch-mediated regulation in C. difficile, highlighting their importance in bacterial adaptability and pathogenicity. Particular attention is given to the ligand specificity and function of known riboswitches in this bacterium. The review also discusses the recent progress that has been made in the development of riboswitch-targeting compounds as potential treatments for C. difficile infections. Future research directions are proposed, emphasizing the need for detailed structural and functional analyses of riboswitches to fully harness their regulatory capabilities for developing new antimicrobial strategies.

In vitro and in vivo assessment of the competence of a novel lytic phage vB_EcoS_UTEC10 targeting multidrug resistant Escherichia coli with a robust biofilm eradication activity

Escherichia coli (E. coli) is a leading cause of human infections worldwide and is considered a major cause of nosocomial infections, sepsis, meningitis and diarrhea. Lately, there has been an alarming increase in the incidence of antimicrobial resistance among clinical E. coli isolates. In the current study, a novel bacteriophage (phage) vB_EcoS_UTEC10 was isolated and characterized. The isolated phage showed high stability over wide temperature and pH ranges beside its promising bacteriolytic activity against multidrug resistant (MDR) E. coli isolates. In addition, vB_EcoS_UTEC10 showed a marked antibiofilm capability against mature E. coli biofilms. Genomic investigation revealed that vB_EcoS_UTEC10 has a double stranded DNA genome that consists of 44,772 bp comprising a total of 73 open reading frames (ORFs), out of which 35 ORFs were annotated as structural or functional proteins, and none were related to antimicrobial resistance or lysogeny. In vivo investigations revealed a promising bacteriolytic activity of vB_EcoS_UTEC10 against MDR E. coli which was further supported by a significant reduction in bacterial load in specimens collected from the phage-treated mice. Histopathology examination demonstrated minimal signs of inflammation and necrosis in the tissues of phage-treated mice compared to the degenerative tissue damage observed in untreated mice. In summary, the present findings suggest that vB_EcoS_UTEC10 has a remarkable ability to eradicate MDR E. coli infections and biofilms. These findings could be further invested for the development of targeted phage therapies that offer a viable alternative to traditional antibiotics against resistant E. coli.

Bacterial extracellular vesicles as intranasal postbiotics: Detailed characterization and interaction with airway cells.

Escherichia coli A0 34/86 (EcO83) is a probiotic strain used in newborns to prevent nosocomial infections and diarrhoea. This bacterium stimulates both pro- and anti-inflammatory cytokine production and its intranasal administration reduces allergic airway inflammation in mice. Despite its benefits, there are concerns about the use of live probiotic bacteria due to potential systemic infections and gene transfer. Extracellular vesicles (EVs) derived from EcO83 (EcO83-EVs) might offer a safer alternative to live bacteria. This study characterizes EcO83-EVs and investigates their interaction with host cells, highlighting their potential as postbiotic therapeutics. EcO83-EVs were isolated, purified, and characterised following the Minimal Information of Studies of Extracellular Vesicles (MISEV) guidelines. Ex vivo studies conducted in human nasal epithelial cells showed that EcO83-EVs increased the expression of proteins linked to oxidative stress and inflammation, indicating an effective interaction between EVs and the host cells. Further in vivo studies in mice demonstrated that EcO83-EVs interact with nasal-associated lymphoid tissue, are internalised by airway macrophages, and stimulate neutrophil recruitment in the lung. Mechanistically, EcO83-EVs activate the NF-κΒ signalling pathway, resulting in the nitric oxide production. EcO83-EVs demonstrate significant potential as a postbiotic alternative to live bacteria, offering a safer option for therapeutic applications. Further research is required to explore their clinical use, particularly in mucosal vaccination and targeted immunotherapy strategies.

The state of play of rodent models for the study of Clostridioides difficile infection.

Clostridioides difficile is the most common cause of nosocomial antibiotic-associated diarrhoea and is responsible for a spectrum of diseases characterized by high levels of recurrence and morbidity. In some cases, complications can lead to death. Currently, several types of animal models have been developed to study various aspects of C. difficile infection (CDI), such as colonization, virulence, transmission and recurrence. These models have also been used to test the role of environmental conditions, such as diet, age and microbiome that modulate infection outcome, and to evaluate several therapeutic strategies. Different rodent models have been used successfully, such as the hamster model and the gnotobiotic and conventional mouse models. These models can be applied to study either the initial CDI infectious process or recurrences. The applications of existing rodent models and their advantages and disadvantages are discussed here.

Exploring the Toxin-Mediated Mechanisms in Clostridioides difficile Infection.

Clostridioides difficile infection (CDI) is the leading cause of nosocomial antibiotic-associated diarrhea, and colitis, with increasing incidence and healthcare costs. Its pathogenesis is primarily driven by toxins produced by the bacterium C. difficile, Toxin A (TcdA) and Toxin B (TcdB). Certain strains produce an additional toxin, the C. difficile transferase (CDT), which further enhances the virulence and pathogenicity of C. difficile. These toxins disrupt colonic epithelial barrier integrity, and induce inflammation and cellular damage, leading to CDI symptoms. Significant progress has been made in the past decade in elucidating the molecular mechanisms of TcdA, TcdB, and CDT, which provide insights into the management of CDI and the future development of novel treatment strategies based on anti-toxin therapies. While antibiotics are common treatments, high recurrence rates necessitate alternative therapies. Bezlotoxumab, targeting TcdB, is the only available anti-toxin, yet limitations persist, prompting ongoing research. This review highlights the current knowledge of the structure and mechanism of action of C. difficile toxins and their role in disease. By comprehensively describing the toxin-mediated mechanisms, this review provides insights for the future development of novel treatment strategies and the management of CDI.

Understanding host immune responses in Clostridioides difficile infection: Implications for pathogenesis and immunotherapy.

Clostridioides difficile (C. difficile) is the predominant causative agent of nosocomial diarrhea worldwide. Infection with C. difficile occurs due to the secretion of large glycosylating toxin proteins, which can lead to toxic megacolon or mortality in susceptible hosts. A critical aspect of C. difficile's biology is its ability to persist asymptomatically within the human host. Individuals harboring asymptomatic colonization or experiencing a single episode of C. difficile infection (CDI) without recurrence exhibit heightened immune responses compared to symptomatic counterparts. The significance of these immune responses cannot be overstated, as they play critical roles in the development, progression, prognosis, and outcomes of CDI. Nonetheless, our current comprehension of the immune responses implicated in CDI remains limited. Therefore, further investigation is imperative to elucidate their underlying mechanisms. This review explores recent advancements in comprehending CDI pathogenesis and how the host immune system response influences disease progression and severity, aiming to enhance our capacity to develop immunotherapy-based treatments for CDI.

Hospital Acquired Diarrhoea in Children: A Study in a Tertiary Care Hospital in Sylhet

Background: Children hospitalized for diseases other than diarrhoea can be infected with an enteric pathogen during their stay at hospital, which may complicate and prolongs the course of illness and hospital stay. Hospital acquired diarrhoea are defined as those occurring more than 72 hours after admission to hospital. Nosocomial diarrhoea second to nosocomial respiratory tract infections in causing morbidity among hospitalized children. Objectives: The study was designed to find the rate of hospital acquired diarrhoea, their risk factors and to observe the clinical features. Method: This cross-sectional observational study was conducted in the inpatient department of Pediatrics in Jalalabad Ragib-Rabeya Medical College, Sylhet over a period of 3 months between July to September 2018. A total number of 274 children aged from 1 month to 5 years were admitted in inpatient department other than diarrhoea were included in the study. During their hospital stay, all patients were followed up daily for development of diarrhoea. Results: Out of 274 children 80 patients developeddiarrhoea 72 hours after admission, the rate of occurrence of hospital acquired diarrhoea was 29.2%. Patients who developed hospital acquired diarrhoea, were initially admitted due to pneumonia accounted for about 65% followed by 12.5% due to malnutrition. Patients aged below two years and staying in hospital for longer duration developed diarrhoea more. Presence of any diarrhoeal patient in a bed close the patient’s bed (p=0.00001), hand washing by mother’s during handling baby (p=0.00001), hand washing by doctors (p=0.00001), and sharing the bathroom with diarrhoeal patient (p=0.000061), were statistically associated with the development of nosocomial diarrhoea. Diarrhoea was mostly watery in nature (80%) having pus (80%) and RBC (100%) on stool microscopy and patients suffered from milder dehydration (80%). Conclusions: Hospital acquired diarrhoea is common in admitted patients, which may complicate the disease course, prolonged the hospital stay. J Rang Med Col. March 2024; Vol. 9, No. 1: 65-70

Estimated global and regional causes of deaths from diarrhoea in children younger than 5 years during 2000–21: a systematic review and Bayesian multinomial analysis

Information on the causes of deaths from diarrhoea in children younger than 5 years is needed to design improved preventive and therapeutic approaches. We aimed to conduct a systematic analysis of studies to report estimates of the causes of deaths from diarrhoea in children younger than 5 years at global and regional levels during 2000-21. For this systematic review and Bayesian multinomial analysis, we included 12 pathogens with the highest attributable incidence in the Global Enteric Multicenter Study. We searched PubMed, Scopus, Embase, Web of Science, Global Health Index Medicus, Global Health OVID, IndMed, Health Information Platform for the Americas (PLISA), Africa-Wide Information, and Cochrane Collaboration for articles published between Jan 1, 2000, and Dec 31, 2020, using the search terms "child", "hospital", "diarrhea", "diarrhoea", "dysentery", "rotavirus", "Escherichia coli", "salmonella", "shigella", "campylobacter", "Vibrio cholerae", "cryptosporidium", "norovirus", "astrovirus", "sapovirus", and "adenovirus". To be included, studies had to have a patient population of children younger than 5 years who were hospitalised for diarrhoea (at least 90% of study participants), at least a 12-month duration, reported prevalence in diarrhoeal stools of at least two of the 12 pathogens, all patients with diarrhoea being included at the study site or a systematic sample, at least 100 patients with diarrhoea, laboratory tests done on rectal swabs or stool samples, and standard laboratory methods (ie, quantitative PCR [qPCR] or non-qPCR). Studies published in any language were included. Studies were excluded if they were limited to nosocomial, chronic, antibiotic-associated, or outbreak diarrhoea or to a specific population (eg, only children with HIV or AIDS). Each article was independently reviewed by two researchers; a third arbitrated in case of disagreement. If both reviewers identified an exclusion criterion, the study was excluded. Data sought were summary estimates. Data on causes from published studies were adjusted when necessary to account for the poor sensitivity of non-qPCR methods and for attributable fraction based on quantification of pathogens in children who are ill or non-ill. The causes of deaths from diarrhoea were modelled on the causes of hospitalisations for diarrhoea. We separately modelled studies reporting causes of diarrhoea in children who were hospitalised in low-income and middle-income countries (LMICs) and in high-income countries (HICs). Of 74 282 papers identified in the initial database search, we included 138 studies (91 included data from LMICs and 47 included data from HICs) from 73 countries. We modelled estimates for 194 WHO member states (hereafter referred to as countries), including 42 HICs and 152 LMICs. We could attribute a cause to 1 003 448 (83·8%) of the estimated 1 197 044 global deaths from diarrhoea in children younger than 5 years in 2000 and 360 730 (81·3%) of the estimated 443 833 global deaths from diarrhoea in children younger than 5 years in 2021. The cause with the largest estimated global attribution was rotavirus; in LMICs, the proportion of deaths from diarrhoea due to rotavirus in children younger than 5 years appeared lower in 2021 (108 322 [24·4%] of 443 342, 95% uncertainty interval 21·6-29·5) than in 2000 (316 382 [26·5%] of 1 196 134, 25·7-28·5), but the 95% CIs overlapped. In 2000, the second largest estimated attribution was norovirus GII (95 817 [8·0%] of 1 196 134 in LMICs and 225 [24·7%] of 910 in HICs); in 2021, Shigella sp had the second largest estimated attribution in LMICs (36 082 [8·1%] of 443 342), but norovirus remained with the second largest estimated attribution in HICs (84 [17·1%] of 490). Our results indicate progress in the reduction of deaths from diarrhoea caused by 12 pathogens in children younger than 5 years in the past two decades. There is a need to increase efforts for prevention, including with rotavirus vaccine, and treatment to eliminate further deaths. Bill & Melinda Gates Foundation via Johns Hopkins University and the University of Virginia.

Fecal Calprotectin in Nosocomial Diarrhea: A Prospective Observational Study

Objective: Fecal calprotectin (FC) has an essential role in differentiating inflammatory diarrhea from functional diarrhea in an outpatient setting; however, its role in nosocomial diarrhea remains not well explored. Materials and Methods: This is a prospective observational study. We included adult inpatients with nosocomial diarrhea and categorized them into diarrhea likely (group A) and unlikely (group B) to have lesions in the colonic mucosa. Group A included infectious diarrhea such as Clostridium difficile and ischemic colitis. Group B comprised tube-feeding diarrhea, non-C. difficile antibiotic-associated diarrhea, and drug-induced diarrhea. The FC levels were compared between the two groups. Results: 135 patients were included, 45 in group A and 90 in group B. Median FC was 902 mg/kg (interquartile range [IQR] 549-2,175) of feces in group A, significantly higher than the median level of 377 mg/kg (IQR 141-664) of feces in group B (p<0.001). The area under the receiver operating characteristic curve was 0.798 (95% confidence interval: 0.717-0.879). At the standard cutoff of 50 mg/kg of feces, the sensitivity and specificity were 97.8% and 7.8%, respectively. Conclusion: FC was significantly higher in nosocomial diarrhea likely to have mucosal lesions; however, its clinical usefulness was limited due to poor specificity.

A168 RATES OF CLOSTRIDIOIDES DIFFICILE INFECTIONS REQUIRING HOSPITALIZATION DURING THE COVID-19 PANDEMIC

Abstract Background Clostridium difficile infection (CDI) is the most common cause of nosocomial infectious diarrhea and is associated with a substantial burden of morbidity and mortality. Most cases of CDI are acquired through health care setting contacts, where appropriate infection prevention and control (IPC) measures such as contact isolation and proper hand hygiene have been demonstrated to prevent horizontal transmission. Aims We aimed to evaluate whether there was a reduction in CDI-related hospitalizations during the COVID-19 pandemic when an increased emphasis was placed on maintaining IPC measures. Methods We analyzed data from the National Inpatient Sample (NIS) between January 2018 and November 2020. The NIS is the largest publicly available administrative health database in the United States, capturing ampersand:003E7 million hospital admissions annually. All analyses were weighted for the complex survey design of the NIS. Temporal trends in monthly admissions for patients with CDI defined using International Classification of Disease 10th revision codes and excluding patients with established CDI carrier status were evaluated using joinpoint regression. Changes over time were expressed as monthly percent change (MPC). To establish whether temporal changes were related to a reduction in CDI or whether these were more generalized effects due to the pandemic, we compared these temporal trends to rates of hospitalizations for inflammatory bowel disease (IBD) and stroke. Results A total of 1,501,415 CDI admissions were identified. The mean age was 64.6 years and 54.2% of patient’s were female. 4.5% of admissions for CDI were associated with in-hospital mortality. Trends in hospitalization are summarized in Figure 1. Compared to the pre-pandemic period (January 2018-December 2019) CDI-related hospitalizations decreased by 9.1%/month [95% CI: -19.2%, +2.0%] (p=0.12) in early 2020 (January-March 2020). This reduction was not sustained: hospitalizations subsequently increased by +8.0% [95% CI: -4.0%, +21.6%] (p=0.19) in mid-2020 (April-June 2020) and were stable after July 2020 (MPC -0.9% [95% CI: -3.5%, +1.7%], p=0.48). Similar patterns were observed for both IBD and stroke-related hospitalizations. Total hospitalizations per month for CDI were similar by June 2020 as compared to the year preceding the pandemic. Conclusions Although an initial decrease in the rates of CDI hospitalizations were seen early in the pandemic (January-March 2020), this pattern was similarly seen for other chronic and acute conditions, and this has not been sustained long-term. Figure 1. Rates of CDI admissions (2018-2020) Funding Agencies None

Anti-S-layer monoclonal antibodies impact Clostridioides difficile physiology

ABSTRACT Clostridioides difficile (C. difficile), a gram-positive anaerobic and spore-forming bacterium, is the leading cause of nosocomial antibiotic-associated diarrhea in adults which is characterized by high levels of recurrence and mortality. Surface (S)-layer Protein A (SlpA), the most abundantly expressed protein on the bacterial surface, plays a crucial role in the early stages of infection although the nature of its involvement in C. difficile physiology is yet to be fully understood. Anti-S-layer antibodies have been identified in the sera of convalescent patients and have been correlated with improved outcomes of C. difficile infection (CDI). However, the precise mechanisms by which anti-S-layer antibodies confer protection to the host remain unknown. In this study, we report the first monoclonal antibodies (mAbs) targeting the S-layer of reference strain 630. Characterization of these mAbs unraveled important roles for the S-layer protein in growth, toxin secretion, and biofilm formation by C. difficile, with differential and even opposite effects of various anti-SlpA mAbs on these functions. Moreover, one anti-SlpA mAb impaired C. difficile growth and conferred sensitivity to lysozyme-induced lysis. The results of this study show that anti-S-layer antibody responses can be beneficial or harmful for the course of CDI and provide important insights for the development of adequate S-layer-targeting therapeutics.

Влияние пробиотиков на функциональную активность кишечной микробиоты беременных и микробиом новорожденных

UpToDate, the issue of the need for the use of probiotics in pregnant women and newborns, especially in infants born in critical condition, remains relevant. Despite the proven effectiveness in the treatment of antibiotic-associated and nosocomial diarrhea, necrotizing enterocolitis, Helicobacter pylori infection, in some clinical situations, further studies are still often required to confirm the positive effect, determining the type, dose and time of taking probiotics. Objective. To evaluate the effect of probiotics on the metabolic activity of the intestinal microflora of pregnant women and the microbiome of newborns. Patients and methods. 236 women were monitored during single pregnancy from 28 to 42 weeks of gestation. Pregnant women were divided into two groups: the main group, whose patients took the probiotic Lactobacillus reuteri Protectis and the comparison group without probiotitcs. All patients had urgent spontaneous physiological labor. The condition at birth and the period of adaptation of newborns were considered satisfactory, all children were breastfed . The condition of the formed mother–child pair was monitored over the next three months. To determine the functional state of the intestinal microbiome in pregnant women, an assessment of endogenous biomarkers of its metabolic activity – short-chain (SCFAs) fatty acids in coprofiltrates. The gas chromatography-mass spectrometry method was used to separate and quantify short-chain fatty acids in stool. The study of intestinal microflora in newborns was carried out on the 20th–25th day of life using the generally accepted microbiological method, in which a qualitative and quantitative assessment of obligate, conditionally pathogenic and pathogenic microorganisms in stool. The mathematical and statistical processing of the obtained research results was carried out using the TIBCO STATISTICA (USA) application software package for a personal computer. The calculation of the average values of the feature (M), standard errors of the average feature (m), and mean square deviations (σ) was performed. In the analysis of the conjugacy tables, the Pearson criterion χ2 was applied to assess the statistical significance of the differences between the two relative indicators. The data in the groups were regarded as statistically significant at p < 0.05 or statistically highly significant at p < 0.001. Results. The obtained results of the study of SCFAs in stool of pregnant women who received probiotics indicated an increase in the functional activity of the intestinal microbiota, improved utilization of these acids by colonocytes, changes in the composition of anaerobic-aerobic populations of microorganisms, leading to an improvement in the redox potential of the intestinal environment. In women who did not receive probiotics, such dynamics of endogenous biomarkers of the functional activity of the intestinal microbiome was not observed. Conditionally pathogenic microflora, various strains of Escherichia coli, and a decrease in the content of lactic acid flora against the background of a high frequency of functional disorders of the intestinal motility were detected in all 236 newborn children in stool. The analysis of the composition of the intestinal microbiome of infants showed a significantly high incidence of a decrease in the number of lactobacilli and an increase in the content of Staphylococcus aureus, Klebsiella pnemoniae, Enterococcus, E. coli strains with low enzymatic properties and hemolytic E. coli in children of the comparison group. At the same time, there were no differences in the content of bifidobacteria, Candida albicans and strains of lactose-negative E. coli in the microbiome of children of both groups, regardless of the intake of probiotics by women. Conclusions. Thus, the intake of L. reuteri Protectis by pregnant women had a positive effect on the activity of the intestinal microflora, which was expressed by a significant increase in the concentration of acetic acid, the total content of SCFAs and the anaerobic index. Despite the fact that all children had disorders in the composition of the intestinal microflora in the form of the presence of S. aureus, K. pnemoniae, Enterococcus, strains of E. coli with weakly enzymatic properties and hemolytic E. coli – the preventive effectiveness of the use of probiotics during pregnancy of their mothers was confirmed by a decrease in the frequency of functional disorders of intestinal motility and the amount of opportunistic microflora, strains of E. coli in the formation of the intestinal microbiome in newborns. Key words: probiotics, pregnant women, newborns, intestinal microbiome, short-chain fatty acids

Implementation of multifaceted diagnostic stewardship for Clostridioides difficile infection during the COVID-19 pandemic at a small Japanese hospital.

Clostridioides difficile infection (CDI) is a common, healthcare-associated infection. However, in Japan, testing for CDI is infrequent, suggesting that its incidence may be underestimated. This study aimed to examine the implementation of a multifaceted, diagnostic stewardship (DS) for CDI in a small Japanese hospital during the coronavirus 2019 pandemic. Before-after study. A small Japanese community hospital. Healthcare workers including physicians, nurses, and pharmacists. A multifaceted intervention including (1) the addition of CD testing criteria to the hospital guidelines; (2) provision of a tutorial on CD testing to physicians, nurses, and pharmacists; (3) assessment by clinical pharmacists and nurses of the need for CD testing in patients with nosocomial diarrhea and issuance of recommendations for CD testing to physicians; (4) reporting of data on the CD testing rate and CDI incidence in the study center. The CD testing rate increased before the pandemic (+0.16/10,000 patient-days (PD); P = .28), decreased significantly during the pandemic (-0.79/10,000 PD; P = .02), and then increased significantly immediately after the implementation of the intervention (+29.6/10,000 PD; P < .01). Similarly, the CDI incidence increased significantly before the pandemic (+0.26/10,000 PD; P = .02) and decreased significantly during the pandemic (-0.49/10,000 PD; P = .01). Implementation of the intervention resulted in an immediate and significant increase in the CDI incidence (+6.2/10,000 PD; P < .01). Multifaceted DS involving multidisciplinary specialists was effective in improving CD testing, suggesting that appropriate testing can contribute to diagnosing CDI accurately.

Comparative Genomics of Clostridioides difficile.

Clostridioides difficile, a Gram-positive spore-forming anaerobic bacterium, has rapidly emerged as the leading cause of nosocomial diarrhoea in hospitals. The availability of large numbers of genome sequences, mainly due to the use of next-generation sequencing methods, has undoubtedly shown their immense advantages in the determination of C. difficile population structure. The implementation of fine-scale comparative genomic approaches has paved the way for global transmission and recurrence studies, as well as more targeted studies, such as the PaLoc or CRISPR/Cas systems. In this chapter, we provide an overview of recent and significant findings on C. difficile using comparative genomic studies with implications for epidemiology, infection control and understanding of the evolution of C. difficile.

157. Implementation of multidisciplinary diagnostic stewardship for Clostridioides difficile infection during the COVID-19 pandemic at a small Japanese hospital

Abstract Background Clostridioides difficile infection (CDI) is a common, healthcare-associated infection. However, its incidence has reportedly declined in the United States owing to the COVID-19 pandemic. On the other hand in Japan, testing for CDI has been infrequent, suggesting that this disease may be underdiagnosed. The present study examined the implementation of multifaceted, diagnostic stewardship for CDI in a small Japanese hospital during the pandemic. Methods The following interventions were introduced at Tama-Nambu Chiiki Hospital, a small community hospital in Tokyo: 1) criteria for CDI testing were added to the hospital's guidelines; 2) clinical pharmacists and nurses assessed the need for CDI testing in patients with nosocomial diarrhea and made recommendations for CDI testing to physicians; 3) a tutorial on CDI testing was given to physicians, nurses, and pharmacists; 4) data on the density of CDI testing and the CDI incidence in the hospital were provided to healthcare workers every three months. The outcomes were CDI testing frequency and the CDI incidence per 10,000 patient days. Segmented regression in interrupted time-series analysis (ITSA) was performed before the pandemic (2018/04-2020/03), after the pandemic (2020/04-2022/03), and after the intervention (2022/04-2023/03). Results The frequency of CDI testing tended to increase before the pandemic (+0.16/10,000 PD, P=0.28) but decreased significantly after the pandemic (-0.79/10,000 PD, P=0.02), then increased significantly immediately after the intervention (+29.6/10,000 PD, P&amp;lt; 0.01). Similarly, the incidence of CDI increased significantly before the pandemic (+0.23/10,000PD, P=0.02) but decreased significantly after the pandemic (-0.45/10,000PD, P=0.01). Implementation of the intervention resulted in an immediate, significant increase in the CDI incidence (+6.8/10,000PD, P&amp;lt; 0.01). Conclusion Multifaceted, diagnostic stewardship involving multiple specialists was effective in improving CDI testing, suggesting that appropriate testing can contribute to the accurate diagnosis of CDI. Disclosures All Authors: No reported disclosures

711. High Prevalence of Positive Cell Cytotoxicity Neutralization Assay in Symptomatic and Asymptomatic Pediatric Oncologic Patients

Abstract Background Clostridium difficile infection (CDI) is the most common cause of nosocomial diarrhea in the United States. This burden is more prevalent and severe in the oncologic population and is associated with greater morbidity and mortality. Diagnostic modalities are limited, and misdiagnosis is high with resultant mismanaged care – inappropriate antibiotics, and potentially missed opportunities for appropriate targeted care towards graft-versus-host disease or other etiologies. To date, no large-scale evaluations have been performed to characterize the incidence of true disease in this population or to help delineate predictive markers for true infections (cell cytotoxicity neutralization assay (CCNA) positivity). Methods This is a multi-center, prospective stool banking study from January 2020 to date enrolling pediatric patients with an oncologic diagnosis admitted at Advocate Children’s Hospital and Comer Children’s Hospital. Stool was collected weekly along with relevant clinical histories and symptomology. Isolates of C. difficile were cultured and CCNA performed. Stool was also collected during episodes of PCR diagnosed CDI. Results 65 unique subjects were enrolled over 183 admissions. 11 samples from 10 patients were thought to represent CDI with PCR positivity noted. Five of these specimens were confirmed as CCNA positive while the remainder did not have active toxin presence. Bristol type 4 stools or &amp;gt; 3 stools in 24 hours were significant factors for modeling CCNA positivity, but not for modeling PCR positivity. Notably 26 stool specimens were CCNA positive, and 21 did not have PCR tests done. Among all CCNA positive specimens, no significant difference was noted in symptomatology or antibiotic use. Conclusion Differentiating true CDI can be challenging. However, even in patients with high risk of alternative GI pathology, the frequency of stooling and stool characteristics can be used. Although considered the gold standard for assessment of disease, CCNA positivity in this population was noted in patients who were not evaluated for disease by their primary providers. Underdiagnosis is possible, but potentially less likely given the absence of clinically significant differentiation in symptoms. Host factors predisposing to disease are likely present. Disclosures Larry K. Kociolek, MD, MSCI, Merck: Grant/Research Support

Clostridioides Difficile in Latin America: An Epidemiological Overview.

Clostridioides difficile infection is one of the most significant causes of nosocomial diarrhea associated with antibiotic use worldwide. In recent years, the incidence of Clostridioides difficile infection in Latin American countries has increased due to the emergence and spread of epidemic Clostridioides difficile strains, such as RT027/NAP1/ST1, RT078/ST11, and RT017/ST37; additionally, endemic multi-drug-resistant strains have recently appeared due to the lack of heterogeneous diagnostic algorithms and guidelines for antibiotic use in each country. The aim of this review is to present the latest information regarding Clostridioides difficile and emphasize the importance of epidemiological surveillance of this pathogen in Latin American countries.

Microbiome profile and calprotectin levels as markers of risk of recurrent Clostridioides difficile infection.

Clostridioides difficile infection (CDI) is the main cause of nosocomial diarrhoea in developed countries. Recurrent CDI (R-CDI), which affects 20%-30% of patients and significantly increases hospital stay and associated costs, is a key challenge. The main objective of this study was to explore the role of the microbiome and calprotectin levels as predictive biomarkers of R-CDI. We prospectively (2019-2021) included patients with a primary episode of CDI. Clinical data and faecal samples were collected. The microbiome was analysed by sequencing the hypervariable V4 region of the 16S rRNA gene on an Illumina Miseq platform. We enrolled 200 patients with primary CDI, of whom 54 developed R-CDI and 146 did not. We analysed 200 primary samples and found that Fusobacterium increased in abundance, while Collinsella, Senegalimassilia, Prevotella and Ruminococcus decreased in patients with recurrent versus non-recurrent disease. Elevated calprotectin levels correlated significantly with R-CDI (p=0.01). We built a risk index for R-CDI, including as prognostic factors age, sex, immunosuppression, toxin B amplification cycle, creatinine levels and faecal calprotectin levels (overall accuracy of 79%). Calprotectin levels and abundance of microbial genera such as Fusobacterium and Prevotella in primary episodes could be useful as early markers of R-CDI. We propose a readily available model for prediction of R-CDI that can be applied at the initial CDI episode. The use of this tool could help to better tailor treatments according to the risk of R-CDI.

Evaluation of the effectiveness and safety of oral vancomycin versus placebo in the prevention of recurrence of Clostridioides difficile infection in patients under systemic antibiotic therapy: a phase III, randomised, double-blind clinical trial

IntroductionClostridioides difficile infection (CDI) is the most prevalent cause of nosocomial bacterial diarrhoea and it is strongly associated with antibiotic use. The recurrence of CDI is a growing medical problem....

Prevention of nosocomial diarrhea using autostrains of lactobacilli isolated from wastewater and from the intestinal biotope of patients

Introduction. The work is devoted to evaluating the results of own studies on the possibility of using autostrains of lactobacilli isolated from wastewater and the intestinal biotope of patients, based on their antagonistic properties to prevent of nosocomial diarrhea associated with toxigenic Clostridioides difficile. There are presented results of studies on an animal model of antibiotic-associated diarrhea to determine the effectiveness of lactobacilli when eliminating toxigenic C. difficile.&#x0D; Materials and methods. Studies were conducted on the antagonistic activity of clinical cultures of lactobacilli isolated from wastewater and intestinal biotope of patients against toxigenic strains of C. difficile isolated from patients with nosocomial diarrhea. Preclinical tests of the efficacy of the selected highly antagonistically active strain of Lactobacillus paracasei CTR079 in vivo were carried out in an animal model of C. difficile-associated infection in mice of the C57BL line.&#x0D; Results. As a result of the studies, lactobacilli with high, medium, and without antagonistic activity were isolated. Antagonistically inactive strains were unable to inhibit the growth of C. difficile, unlike highly active strains. A strain of Lactobacillus paracasei CTR079 was selected to study the possibility of its use as a probiotic strain for the prevention and treatment of C. difficile associated infection in an in vivo experiment. Various changes in the intestinal epithelium as a result of the development of C. difficile-associated infection. &#x0D; Limitations of the study. As part of the study, all isolated strains of lactobacilli were identified and stored for the study of biological, genetic properties, and production of bacteriocins.&#x0D; Conclusion. As a result of the studies, the use of highly active strains of lactobacilli was established to be a promising direction for the prevention and treatment of nosocomial diarrhea, which will reduce the spread of C. difficile among patients and in the environment of medical institutions.